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1.  Pulmonary Rehabilitation for Patients With Chronic Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this evidence-based review was to determine the effectiveness and cost-effectiveness of pulmonary rehabilitation in the management of chronic obstructive pulmonary disease (COPD).
Technology
Pulmonary rehabilitation refers to a multidisciplinary program of care for patients with chronic respiratory impairment that is individually tailored and designed to optimize physical and social performance and autonomy. Exercise training is the cornerstone of pulmonary rehabilitation programs, though they may also include components such as patient education and psychological support. Pulmonary rehabilitation is recommended as the standard of care in the treatment and rehabilitation of patients with COPD who remain symptomatic despite treatment with bronchodilators.
For the purpose of this review, the Medical Advisory Secretariat focused on pulmonary rehabilitation programs as defined by the Cochrane Collaboration—that is, any inpatient, outpatient, or home-based rehabilitation program lasting at least 4 weeks that includes exercise therapy with or without any form of education and/or psychological support delivered to patients with exercise limitations attributable to COPD.
Research Questions
What is the effectiveness and cost-effectiveness of pulmonary rehabilitation compared with usual care (UC) for patients with stable COPD?
Does early pulmonary rehabilitation (within 1 month of hospital discharge) in patients who had an acute exacerbation of COPD improve outcomes compared with UC (or no rehabilitation)?
Do maintenance or postrehabilitation programs for patients with COPD who have completed a pulmonary rehabilitation program improve outcomes compared with UC?
Research Methods
Literature Search
Search Strategy
For Research Questions 1and 2, a literature search was performed on August 10, 2010 for studies published from January 1, 2004 to July 31, 2010. For Research Question 3, a literature search was performed on February 3, 2011 for studies published from January 1, 2000 to February 3, 2011. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists and health technology assessment websites were also examined for any additional relevant studies not identified through the systematic search.
Inclusion Criteria
Research questions 1 and 2:
published between January 1, 2004 and July 31, 2010
randomized controlled trials, systematic reviews, and meta-analyses
COPD study population
studies comparing pulmonary rehabilitation with UC (no pulmonary rehabilitation)
duration of pulmonary rehabilitation program ≥ 6 weeks
pulmonary rehabilitation program had to include at minimum exercise training
Research question 3:
published between January 1, 2000 and February 3, 2011
randomized controlled trials, systematic reviews, and meta-analyses
COPD study population
studies comparing a maintenance or postrehabilitation program with UC (standard follow-up)
duration of pulmonary rehabilitation program ≥ 6 weeks
initial pulmonary rehabilitation program had to include at minimum exercise training
Exclusion Criteria
Research questions 1, 2, and 3:
grey literature
duplicate publications
non-English language publications
study population ≤ 18 years of age
studies conducted in a palliative population
studies that did not report primary outcome of interest
Additional exclusion criteria for research question 3:
studies with ≤ 2 sessions/visits per month
Outcomes of Interest
The primary outcomes of interest for the stable COPD population were exercise capacity and health-related quality of life (HRQOL). For the COPD population following an exacerbation, the primary outcomes of interest were hospital readmissions and HRQOL. The primary outcomes of interest for the COPD population undertaking maintenance programs were functional exercise capacity and HRQOL.
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Research Question 1: Effect of Pulmonary Rehabilitation on Outcomes in Stable COPD
Seventeen randomized controlled trials met the inclusion criteria and were included in this review.
The following conclusions are based on moderate quality of evidence.
Pulmonary rehabilitation including at least 4 weeks of exercise training leads to clinically and statistically significant improvements in HRQOL in patients with COPD.1
Pulmonary rehabilitation also leads to a clinically and statistically significant improvement in functional exercise capacity2 (weighted mean difference, 54.83 m; 95% confidence interval, 35.63–74.03; P < 0.001).
Research Question 2: Effect of Pulmonary Rehabilitation on Outcomes Following an Acute Exacerbation of COPD
Five randomized controlled trials met the inclusion criteria and are included in this review. The following conclusion is based on moderate quality of evidence.
Pulmonary rehabilitation (within 1 month of hospital discharge) after acute exacerbation significantly reduces hospital readmissions (relative risk, 0.50; 95% confidence interval, 0.33–0.77; P = 0.001) and leads to a statistically and clinically significant improvement in HRQOL.3
Research Question 3: Effect of Pulmonary Rehabilitation Maintenance Programs on COPD Outcomes
Three randomized controlled trials met the inclusion criteria and are included in this review. The conclusions are based on a low quality of evidence and must therefore be considered with caution.
Maintenance programs have a nonsignificant effect on HRQOL and hospitalizations.
Maintenance programs have a statistically but not clinically significant effect on exercise capacity (P = 0.01). When subgrouped by intensity and quality of study, maintenance programs have a statistically and marginally clinically significant effect on exercise capacity.
PMCID: PMC3384375  PMID: 23074434
2.  Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients with Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this analysis was to determine the effectiveness of the influenza vaccination and the pneumococcal vaccination in patients with chronic obstructive pulmonary disease (COPD) in reducing the incidence of influenza-related illness or pneumococcal pneumonia.
Clinical Need: Condition and Target Population
Influenza Disease
Influenza is a global threat. It is believed that the risk of a pandemic of influenza still exists. Three pandemics occurred in the 20th century which resulted in millions of deaths worldwide. The fourth pandemic of H1N1 influenza occurred in 2009 and affected countries in all continents.
Rates of serious illness due to influenza viruses are high among older people and patients with chronic conditions such as COPD. The influenza viruses spread from person to person through sneezing and coughing. Infected persons can transfer the virus even a day before their symptoms start. The incubation period is 1 to 4 days with a mean of 2 days. Symptoms of influenza infection include fever, shivering, dry cough, headache, runny or stuffy nose, muscle ache, and sore throat. Other symptoms such as nausea, vomiting, and diarrhea can occur.
Complications of influenza infection include viral pneumonia, secondary bacterial pneumonia, and other secondary bacterial infections such as bronchitis, sinusitis, and otitis media. In viral pneumonia, patients develop acute fever and dyspnea, and may further show signs and symptoms of hypoxia. The organisms involved in bacterial pneumonia are commonly identified as Staphylococcus aureus and Hemophilus influenza. The incidence of secondary bacterial pneumonia is most common in the elderly and those with underlying conditions such as congestive heart disease and chronic bronchitis.
Healthy people usually recover within one week but in very young or very old people and those with underlying medical conditions such as COPD, heart disease, diabetes, and cancer, influenza is associated with higher risks and may lead to hospitalization and in some cases death. The cause of hospitalization or death in many cases is viral pneumonia or secondary bacterial pneumonia. Influenza infection can lead to the exacerbation of COPD or an underlying heart disease.
Streptococcal Pneumonia
Streptococcus pneumoniae, also known as pneumococcus, is an encapsulated Gram-positive bacterium that often colonizes in the nasopharynx of healthy children and adults. Pneumococcus can be transmitted from person to person during close contact. The bacteria can cause illnesses such as otitis media and sinusitis, and may become more aggressive and affect other areas of the body such as the lungs, brain, joints, and blood stream. More severe infections caused by pneumococcus are pneumonia, bacterial sepsis, meningitis, peritonitis, arthritis, osteomyelitis, and in rare cases, endocarditis and pericarditis.
People with impaired immune systems are susceptible to pneumococcal infection. Young children, elderly people, patients with underlying medical conditions including chronic lung or heart disease, human immunodeficiency virus (HIV) infection, sickle cell disease, and people who have undergone a splenectomy are at a higher risk for acquiring pneumococcal pneumonia.
Technology
Influenza and Pneumococcal Vaccines
Trivalent Influenza Vaccines in Canada
In Canada, 5 trivalent influenza vaccines are currently authorized for use by injection. Four of these are formulated for intramuscular use and the fifth product (Intanza®) is formulated for intradermal use.
The 4 vaccines for intramuscular use are:
Fluviral (GlaxoSmithKline), split virus, inactivated vaccine, for use in adults and children ≥ 6 months;
Vaxigrip (Sanofi Pasteur), split virus inactivated vaccine, for use in adults and children ≥ 6 months;
Agriflu (Novartis), surface antigen inactivated vaccine, for use in adults and children ≥ 6 months; and
Influvac (Abbott), surface antigen inactivated vaccine, for use in persons ≥ 18 years of age.
FluMist is a live attenuated virus in the form of an intranasal spray for persons aged 2 to 59 years. Immunization with current available influenza vaccines is not recommended for infants less than 6 months of age.
Pneumococcal Vaccine
Pneumococcal polysaccharide vaccines were developed more than 50 years ago and have progressed from 2-valent vaccines to the current 23-valent vaccines to prevent diseases caused by 23 of the most common serotypes of S pneumoniae. Canada-wide estimates suggest that approximately 90% of cases of pneumococcal bacteremia and meningitis are caused by these 23 serotypes. Health Canada has issued licenses for 2 types of 23-valent vaccines to be injected intramuscularly or subcutaneously:
Pneumovax 23® (Merck & Co Inc. Whitehouse Station, NJ, USA), and
Pneumo 23® (Sanofi Pasteur SA, Lion, France) for persons 2 years of age and older.
Other types of pneumococcal vaccines licensed in Canada are for pediatric use. Pneumococcal polysaccharide vaccine is injected only once. A second dose is applied only in some conditions.
Research Questions
What is the effectiveness of the influenza vaccination and the pneumococcal vaccination compared with no vaccination in COPD patients?
What is the safety of these 2 vaccines in COPD patients?
What is the budget impact and cost-effectiveness of these 2 vaccines in COPD patients?
Research Methods
Literature search
Search Strategy
A literature search was performed on July 5, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 2000 to July 5, 2010. The search was updated monthly through the AutoAlert function of the search up to January 31, 2011. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Articles with an unknown eligibility were reviewed with a second clinical epidemiologist and then a group of epidemiologists until consensus was established. Data extraction was carried out by the author.
Inclusion Criteria
studies comparing clinical efficacy of the influenza vaccine or the pneumococcal vaccine with no vaccine or placebo;
randomized controlled trials published between January 1, 2000 and January 31, 2011;
studies including patients with COPD only;
studies investigating the efficacy of types of vaccines approved by Health Canada;
English language studies.
Exclusion Criteria
non-randomized controlled trials;
studies investigating vaccines for other diseases;
studies comparing different variations of vaccines;
studies in which patients received 2 or more types of vaccines;
studies comparing different routes of administering vaccines;
studies not reporting clinical efficacy of the vaccine or reporting immune response only;
studies investigating the efficacy of vaccines not approved by Health Canada.
Outcomes of Interest
Primary Outcomes
Influenza vaccination: Episodes of acute respiratory illness due to the influenza virus.
Pneumococcal vaccination: Time to the first episode of community-acquired pneumonia either due to pneumococcus or of unknown etiology.
Secondary Outcomes
rate of hospitalization and mechanical ventilation
mortality rate
adverse events
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses. The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Efficacy of the Influenza Vaccination in Immunocompetent Patients With COPD
Clinical Effectiveness
The influenza vaccination was associated with significantly fewer episodes of influenza-related acute respiratory illness (ARI). The incidence density of influenza-related ARI was:
All patients: vaccine group: (total of 4 cases) = 6.8 episodes per 100 person-years; placebo group: (total of 17 cases) = 28.1 episodes per 100 person-years, (relative risk [RR], 0.2; 95% confidence interval [CI], 0.06−0.70; P = 0.005).
Patients with severe airflow obstruction (forced expiratory volume in 1 second [FEV1] < 50% predicted): vaccine group: (total of 1 case) = 4.6 episodes per 100 person-years; placebo group: (total of 7 cases) = 31.2 episodes per 100 person-years, (RR, 0.1; 95% CI, 0.003−1.1; P = 0.04).
Patients with moderate airflow obstruction (FEV1 50%−69% predicted): vaccine group: (total of 2 cases) = 13.2 episodes per 100 person-years; placebo group: (total of 4 cases) = 23.8 episodes per 100 person-years, (RR, 0.5; 95% CI, 0.05−3.8; P = 0.5).
Patients with mild airflow obstruction (FEV1 ≥ 70% predicted): vaccine group: (total of 1 case) = 4.5 episodes per 100 person-years; placebo group: (total of 6 cases) = 28.2 episodes per 100 person-years, (RR, 0.2; 95% CI, 0.003−1.3; P = 0.06).
The Kaplan-Meier survival analysis showed a significant difference between the vaccinated group and the placebo group regarding the probability of not acquiring influenza-related ARI (log-rank test P value = 0.003). Overall, the vaccine effectiveness was 76%. For categories of mild, moderate, or severe COPD the vaccine effectiveness was 84%, 45%, and 85% respectively.
With respect to hospitalization, fewer patients in the vaccine group compared with the placebo group were hospitalized due to influenza-related ARIs, although these differences were not statistically significant. The incidence density of influenza-related ARIs that required hospitalization was 3.4 episodes per 100 person-years in the vaccine group and 8.3 episodes per 100 person-years in the placebo group (RR, 0.4; 95% CI, 0.04−2.5; P = 0.3; log-rank test P value = 0.2). Also, no statistically significant differences between the 2 groups were observed for the 3 categories of severity of COPD.
Fewer patients in the vaccine group compared with the placebo group required mechanical ventilation due to influenza-related ARIs. However, these differences were not statistically significant. The incidence density of influenza-related ARIs that required mechanical ventilation was 0 episodes per 100 person-years in the vaccine group and 5 episodes per 100 person-years in the placebo group (RR, 0.0; 95% CI, 0−2.5; P = 0.1; log-rank test P value = 0.4). In addition, no statistically significant differences between the 2 groups were observed for the 3 categories of severity of COPD. The effectiveness of the influenza vaccine in preventing influenza-related ARIs and influenza-related hospitalization was not related to age, sex, severity of COPD, smoking status, or comorbid diseases.
safety
Overall, significantly more patients in the vaccine group than the placebo group experienced local adverse reactions (vaccine: 17 [27%], placebo: 4 [6%]; P = 0.002). Significantly more patients in the vaccine group than the placebo group experienced swelling (vaccine 4, placebo 0; P = 0.04) and itching (vaccine 4, placebo 0; P = 0.04). Systemic reactions included headache, myalgia, fever, and skin rash and there were no significant differences between the 2 groups for these reactions (vaccine: 47 [76%], placebo: 51 [81%], P = 0.5).
With respect to lung function, dyspneic symptoms, and exercise capacity, there were no significant differences between the 2 groups at 1 week and at 4 weeks in: FEV1, maximum inspiratory pressure at residual volume, oxygen saturation level of arterial blood, visual analogue scale for dyspneic symptoms, and the 6 Minute Walking Test for exercise capacity.
There was no significant difference between the 2 groups with regard to the probability of not acquiring total ARIs (influenza-related and/or non-influenza-related); (log-rank test P value = 0.6).
Summary of Efficacy of the Pneumococcal Vaccination in Immunocompetent Patients With COPD
Clinical Effectiveness
The Kaplan-Meier survival analysis showed no significant differences between the group receiving the penumoccocal vaccination and the control group for time to the first episode of community-acquired pneumonia due to pneumococcus or of unknown etiology (log-rank test 1.15; P = 0.28). Overall, vaccine efficacy was 24% (95% CI, −24 to 54; P = 0.33).
With respect to the incidence of pneumococcal pneumonia, the Kaplan-Meier survival analysis showed a significant difference between the 2 groups (vaccine: 0/298; control: 5/298; log-rank test 5.03; P = 0.03).
Hospital admission rates and median length of hospital stays were lower in the vaccine group, but the difference was not statistically significant. The mortality rate was not different between the 2 groups.
Subgroup Analysis
The Kaplan-Meier survival analysis showed significant differences between the vaccine and control groups for pneumonia due to pneumococcus and pneumonia of unknown etiology, and when data were analyzed according to subgroups of patients (age < 65 years, and severe airflow obstruction FEV1 < 40% predicted). The accumulated percentage of patients without pneumonia (due to pneumococcus and of unknown etiology) across time was significantly lower in the vaccine group than in the control group in patients younger than 65 years of age (log-rank test 6.68; P = 0.0097) and patients with a FEV1 less than 40% predicted (log-rank test 3.85; P = 0.0498).
Vaccine effectiveness was 76% (95% CI, 20−93; P = 0.01) for patients who were less than 65 years of age and −14% (95% CI, −107 to 38; P = 0.8) for those who were 65 years of age or older. Vaccine effectiveness for patients with a FEV1 less than 40% predicted and FEV1 greater than or equal to 40% predicted was 48% (95% CI, −7 to 80; P = 0.08) and −11% (95% CI, −132 to 47; P = 0.95), respectively. For patients who were less than 65 years of age (FEV1 < 40% predicted), vaccine effectiveness was 91% (95% CI, 35−99; P = 0.002).
Cox modelling showed that the effectiveness of the vaccine was dependent on the age of the patient. The vaccine was not effective in patients 65 years of age or older (hazard ratio, 1.53; 95% CI, 0.61−a2.17; P = 0.66) but it reduced the risk of acquiring pneumonia by 80% in patients less than 65 years of age (hazard ratio, 0.19; 95% CI, 0.06−0.66; P = 0.01).
safety
No patients reported any local or systemic adverse reactions to the vaccine.
PMCID: PMC3384373  PMID: 23074431
3.  Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this evidence-based analysis was to determine the effectiveness and cost-effectiveness of multidisciplinary care (MDC) compared with usual care (UC, single health care provider) for the treatment of stable chronic obstructive pulmonary disease (COPD).
Clinical Need: Condition and Target Population
Chronic obstructive pulmonary disease is a progressive disorder with episodes of acute exacerbations associated with significant morbidity and mortality. Cigarette smoking is linked causally to COPD in more than 80% of cases. Chronic obstructive pulmonary disease is among the most common chronic diseases worldwide and has an enormous impact on individuals, families, and societies through reduced quality of life and increased health resource utilization and mortality.
The estimated prevalence of COPD in Ontario in 2007 was 708,743 persons.
Technology
Multidisciplinary care involves professionals from a range of disciplines, working together to deliver comprehensive care that addresses as many of the patient’s health care and psychosocial needs as possible.
Two variables are inherent in the concept of a multidisciplinary team: i) the multidisciplinary components such as an enriched knowledge base and a range of clinical skills and experiences, and ii) the team components, which include but are not limited to, communication and support measures. However, the most effective number of team members and which disciplines should comprise the team for optimal effect is not yet known.
Research Question
What is the effectiveness and cost-effectiveness of MDC compared with UC (single health care provider) for the treatment of stable COPD?
Research Methods
Literature Search
Search Strategy
A literature search was performed on July 19, 2010 using OVID MEDLINE, OVID MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination database, for studies published from January 1, 1995 until July 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search.
Inclusion Criteria
health technology assessments, systematic reviews, or randomized controlled trials
studies published between January 1995 and July 2010;
COPD study population
studies comparing MDC (2 or more health care disciplines participating in care) compared with UC (single health care provider)
Exclusion Criteria
grey literature
duplicate publications
non-English language publications
study population less than 18 years of age
Outcomes of Interest
hospital admissions
emergency department (ED) visits
mortality
health-related quality of life
lung function
Quality of Evidence
The quality of each included study was assessed, taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Six randomized controlled trials were obtained from the literature search. Four of the 6 studies were completed in the United States. The sample size of the 6 studies ranged from 40 to 743 participants, with a mean study sample between 66 and 71 years of age. Only 2 studies characterized the study sample in terms of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) COPD stage criteria, and in general the description of the study population in the other 4 studies was limited. The mean percent predicted forced expiratory volume in 1 second (% predicted FEV1) among study populations was between 32% and 59%. Using this criterion, 3 studies included persons with severe COPD and 2 with moderate COPD. Information was not available to classify the population in the sixth study.
Four studies had MDC treatment groups which included a physician. All studies except 1 reported a respiratory specialist (i.e., respiratory therapist, specialist nurse, or physician) as part of the multidisciplinary team. The UC group was comprised of a single health care practitioner who may or may not have been a respiratory specialist.
A meta-analysis was completed for 5 of the 7 outcome measures of interest including:
health-related quality of life,
lung function,
all-cause hospitalization,
COPD-specific hospitalization, and
mortality.
There was only 1 study contributing to the outcome of all-cause and COPD-specific ED visits which precluded pooling data for these outcomes. Subgroup analyses were not completed either because heterogeneity was not significant or there were a small number of studies that were meta-analysed for the outcome.
Quality of Life
Three studies reported results of quality of life assessment based on the St. George’s Respiratory Questionnaire (SGRQ). A mean decrease in the SGRQ indicates an improvement in quality of life while a mean increase indicates deterioration in quality of life. In all studies the mean change score from baseline to the end time point in the MDC treatment group showed either an improvement compared with the control group or less deterioration compared with the control group. The mean difference in change scores between MDC and UC groups was statistically significant in all 3 studies. The pooled weighted mean difference in total SGRQ score was −4.05 (95% confidence interval [CI], −6.47 to 1.63; P = 0.001). The GRADE quality of evidence was assessed as low for this outcome.
Lung Function
Two studies reported results of the FEV1 % predicted as a measure of lung function. A negative change from baseline infers deterioration in lung function and a positive change from baseline infers an improvement in lung function. The MDC group showed a statistically significant improvement in lung function up to 12 months compared with the UC group (P = 0.01). However this effect is not maintained at 2-year follow-up (P = 0.24). The pooled weighted mean difference in FEV1 percent predicted was 2.78 (95% CI, −1.82 to −7.37). The GRADE quality of evidence was assessed as very low for this outcome indicating that an estimate of effect is uncertain.
Hospital Admissions
All-Cause
Four studies reported results of all-cause hospital admissions in terms of number of persons with at least 1 admission during the follow-up period. Estimates from these 4 studies were pooled to determine a summary estimate. There is a statistically significant 25% relative risk (RR) reduction in all-cause hospitalizations in the MDC group compared with the UC group (P < 0.001). The index of heterogeneity (I2) value is 0%, indicating no statistical heterogeneity between studies. The GRADE quality of evidence was assessed as moderate for this outcome, indicating that further research may change the estimate of effect.
COPD-Specific Hospitalization
Three studies reported results of COPD-specific hospital admissions in terms of number of persons with at least 1 admission during the follow-up period. Estimates from these 3 studies were pooled to determine a summary estimate. There is a statistically significant 33% RR reduction in all-cause hospitalizations in the MDC group compared with the UC group (P = 0.002). The I2 value is 0%, indicating no statistical heterogeneity between studies. The GRADE quality of evidence was assessed as moderate for this outcome, indicating that further research may change the estimate of effect.
Emergency Department Visits
All-Cause
Two studies reported results of all-cause ED visits in terms of number of persons with at least 1 visit during the follow-up period. There is a statistically nonsignificant reduction in all-cause ED visits when data from these 2 studies are pooled (RR, 0.64; 95% CI, 0.31 to −1.33; P = 0.24). The GRADE quality of evidence was assessed as very low for this outcome indicating that an estimate of effect is uncertain.
COPD-Specific
One study reported results of COPD-specific ED visits in terms of number of persons with at least 1 visit during the follow-up period. There is a statistically significant 41% reduction in COPD-specific ED visits when the data from these 2 studies are pooled (RR, 0.59; 95% CI, 0.43−0.81; P < 0.001). The GRADE quality of evidence was assessed as moderate for this outcome.
Mortality
Three studies reported the mortality during the study follow-up period. Estimates from these 3 studies were pooled to determine a summary estimate. There is a statistically nonsignificant reduction in mortality between treatment groups (RR, 0.81; 95% CI, 0.52−1.27; P = 0.36). The I2 value is 19%, indicating low statistical heterogeneity between studies. All studies had a 12-month follow-up period. The GRADE quality of evidence was assessed as low for this outcome.
Conclusions
Significant effect estimates with moderate quality of evidence were found for all-cause hospitalization, COPD-specific hospitalization, and COPD-specific ED visits (Table ES1). A significant estimate with low quality evidence was found for the outcome of quality of life (Table ES2). All other outcome measures were nonsignificant and supported by low or very low quality of evidence.
Summary of Dichotomous Data
Abbreviations: CI, confidence intervals; COPD, chronic obstructive pulmonary disease; n, number.
Summary of Continuous Data
Abbreviations: CI, confidence intervals; FEV1, forced expiratory volume in 1 second; n, number; SGRQ, St. George’s Respiratory Questionnaire.
PMCID: PMC3384374  PMID: 23074433
4.  Experiences of Living and Dying With COPD 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-Term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective of Analysis
The objective of this analysis was to review empirical qualitative research on the experiences of patients with chronic obstructive pulmonary disease (COPD), informal caregivers (“carers”), and health care providers—from the point of diagnosis, through daily living and exacerbation episodes, to the end of life.
Clinical Need and Target Population
Qualitative empirical studies (from social sciences, clinical, and related fields) can offer important information about how patients experience their condition. This exploration of the qualitative literature offers insights into patients’ perspectives on COPD, their needs, and how interventions might affect their experiences. The experiences of caregivers are also explored.
Research Question
What do patients with COPD, their informal caregivers (“carers”), and health care providers experience over the course of COPD?
Research Methods
Literature Search
Search Strategy
Literature searches for studies published from January 1, 2000, to November 2010 were performed on November 29, 2010, using OVID MEDLINE; on November 26, 2010, using ISI Web of Science; and on November 28, 2010, using EBSCO Cumulative Index to Nursing and Allied Health Literature (CINAHL). Titles and abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. One additional report, highly relevant to the synthesis, appeared in early 2011 during the drafting of this analysis and was included post hoc.
Inclusion Criteria
English-language full reports
studies published between January 1, 2000, and November 2010
primary qualitative empirical research (using any descriptive or interpretive qualitative methodology, including the qualitative component of mixed-methods studies) and secondary syntheses of primary qualitative empirical research
studies addressing any aspect of the experiences of living or dying with COPD from the perspective of persons at risk, patients, health care providers, or informal carers; studies addressing multiple conditions were included if COPD was addressed explicitly
Exclusion Criteria
studies addressing topics other than the experiences of living or dying with COPD from the perspective of persons at risk, patients, health care providers, or informal carers
studies labelled “qualitative” but not using a qualitative descriptive or interpretive methodology (e.g., case studies, experiments, or observational analysis using qualitative categorical variables)
quantitative research (i.e., using statistical hypothesis testing, using primarily quantitative data or analyses, or expressing results in quantitative or statistical terms)
studies that did not pose an empirical research objective or question, or involve the primary or secondary analysis of empirical data
Outcomes of Interest
qualitative descriptions and interpretations (narrative or theoretical) of personal and social experiences of COPD
Summary of Findings
Experiences at Diagnosis
Patients typically seek initial treatment for an acute episode rather than for chronic early symptoms of COPD.
Many patients initially misunderstand terms such as COPD, chronic obstructive pulmonary disease, or exacerbation.
Patients may not realize that COPD is incurable and fatal; some physicians themselves do not consider early COPD to be a fatal disease.
Smokers may not readily understand or agree with the idea that smoking caused or worsens their COPD. Those who believe there is a causal link may feel regret or shame.
Experiences of Living Day to Day
COPD patients experience alternating good days and bad days. A roller-coaster pattern of ups and downs becomes apparent, and COPD becomes a way of life.
Patients use many means (social, psychological, medical, organizational) to control what they can, and to cope with what they cannot. Economic hardship, comorbidities, language barriers, and low health literacy can make coping more difficult.
Increasing vulnerability and unpredictable setbacks make patients dependent on others for practical assistance, but functional limitations, institutional living or self-consciousness can isolate patients from the people they need.
For smokers, medical advice to quit can conflict with increased desire to smoke as a coping strategy.
Many of the factors that isolate COPD patients from social contact also isolate them from health care.
Experiences of Exacerbations
Patients may not always attribute repeated exacerbations to advancing disease, instead seeing them as temporary setbacks caused by activities, environmental factors, faltering self-management, or infection.
Lack of confidence in community-based services leads some patients to seek hospital admission, but patients also feel vulnerable when hospitalized. They may feel dependent on others for care or traumatized by hospital care routines.
Upon hospital discharge following an exacerbation, patients may face new levels of uncertainty about their illness, prognosis, care providers, and supports.
Experiences of the End of Life
Patients tend to be poorly informed about the long-term prognosis of COPD and what to expect toward the end of life; this lack of understanding impairs quality of life as the disease progresses.
As the end of life approaches, COPD patients face the usual challenges of daily living, but in a context of increasing exacerbations and deepening dependency. Activities and mobility decrease, and life may become confined.
Some clinicians have difficulty identifying the beginning of “the end of life,” given the unpredictable course of COPD. Long-term physician-patient relationships, familiarity and understanding, trust, good communication skills, sensitivity, and secure discussion settings can help facilitate end-of-life discussions.
Divergent meanings and goals of palliative care in COPD lead to confusion about whether such services are the responsibility of home care, primary care, specialty care, or even critical care. Palliative end-of-life care may not be anticipated prior to referral for such care. A palliative care referral can convey the demoralizing message that providers have “given up.”
Experiences of Carers
Carers’ challenges often echo patients’ challenges, and include anxiety, uncertainty about the future, helplessness, powerlessness, depression, difficulties maintaining employment, loss of mobility and freedoms, strained relationships, and growing social isolation.
Carers feel pressured by their many roles, struggling to maintain patience when they feel overwhelmed, and often feeling guilty about not doing enough.
Carers often face their own health problems and may have difficulty sustaining employment.
Synthesis: A Disease Trajectory Reflecting Patient Experiences
The flux of needs in COPD calls for service continuity and flexibility to allow both health care providers and patients to respond to the unpredictable yet increasing demands of the disease over time.
PMCID: PMC3384365  PMID: 23074423
5.  Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this health technology assessment was to determine the effectiveness and cost-effectiveness of noninvasive ventilation for stable chronic obstructive pulmonary disease (COPD).
Clinical Need: Condition and Target Population
Noninvasive ventilation is used for COPD patients with chronic respiratory failure. Chronic respiratory failure in COPD patients may be due to the inability of the pulmonary system to coordinate ventilation, leading to adverse arterial levels of oxygen and carbon dioxide. Noninvasive ventilation in stable COPD patients has the potential to improve quality of life, prolong survival, and improve gas exchange and sleep quality in patients who are symptomatic after optimal therapy, have hypercapnia or nocturnal hypoventilation and mild hypercapnia, and are frequently hospitalized.
Technology
Noninvasive positive pressure ventilation (NPPV) is any form of positive ventilatory support without the use of an endotracheal tube. For stable COPD, the standard of care when using noninvasive ventilation is bilevel positive airway pressure (BiPAP). Bilevel positive airway pressure involves both inspiratory and expiratory pressure, high during inspiration and lower during expiration. It acts as a pressure support to accentuate a patient’s inspiratory efforts. The gradient between pressures maintains alveolar ventilation and helps to reduce carbon dioxide levels. Outpatients typically use BiPAP at night. Additional advantages of using BiPAP include resting of respiratory muscles, decreased work of breathing, and control of obstructive hypopnea.
Research Question
What is the effectiveness and cost-effectiveness of noninvasive ventilation, compared with no ventilation while receiving usual care, for stable COPD patients?
Research Methods
Literature Search
Search Strategy
A literature search was performed on December 3, 2010, using OVID MEDLINE, OVID MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination database for studies published from January 1, 2004 to December 3, 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. When the reviewer was unsure of the eligibility of articles, a second clinical epidemiologist and then a group of epidemiologists reviewed these until consensus was reached.
Inclusion Criteria
full-text English language articles,
studies published between January 1, 2004 and December 3, 2010,
journal articles that report on the effectiveness or cost-effectiveness of noninvasive ventilation,
clearly described study design and methods, and
health technology assessments, systematic reviews, meta-analyses, randomized controlled trials (RCTs).
Exclusion Criteria
non-English papers
animal or in vitro studies
case reports, case series, or case-case studies
cross-over RCTs
studies on noninvasive negative pressure ventilation (e.g., iron lung)
studies that combine ventilation therapy with other regimens (e.g., daytime NPPV plus exercise or pulmonary rehabilitation)
studies on heliox with NPPV
studies on pulmonary rehabilitation with NPPV
Outcomes of Interest
mortality/survival
hospitalizations/readmissions
length of stay in hospital
forced expiratory volume
arterial partial pressure of oxygen
arterial partial pressure of carbon dioxide
dyspnea
exercise tolerance
health-related quality of life
Note: arterial pressure of oxygen and carbon dioxide are surrogate outcomes.
Statistical Methods
A meta-analysis and an analysis of individual studies were performed using Review Manager Version 5. For continuous data, a mean difference was calculated, and for dichotomous data, a relative risk ratio was calculated for RCTs. For continuous variables with mean baseline and mean follow-up data, a change value was calculated as the difference between the 2 mean values.
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Conclusions
The following conclusions refer to stable, severe COPD patients receiving usual care.
Short-Term Studies
Based on low quality of evidence, there is a beneficial effect of NPPV compared with no ventilation on oxygen gas exchange, carbon dioxide gas exchange, and exercise tolerance measured using the 6 Minute Walking Test.
Based on very low quality of evidence, there is no effect of NPPV therapy on lung function measured as forced expiratory volume in 1 second (Type II error not excluded).
Long-Term Studies
Based on moderate quality of evidence, there is no effect of NPPV therapy for the outcomes of mortality, lung function measured as forced expiratory volume in 1 second, and exercise tolerance measured using the 6 Minute Walking Test.
Based on low quality of evidence, there is no effect of NPPV therapy for the outcomes of oxygen gas exchange and carbon dioxide gas exchange (Type II error not excluded).
Qualitative Assessment
Based on low quality of evidence, there is a beneficial effect of NPPV compared with no ventilation for dyspnea based on reduced Borg score or Medical Research Council dyspnea score.
Based on moderate quality of evidence, there is no effect of NPPV therapy for hospitalizations.
Health-related quality of life could not be evaluated.
PMCID: PMC3384378  PMID: 23074437
6.  Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this analysis was to conduct an evidence-based assessment of home telehealth technologies for patients with chronic obstructive pulmonary disease (COPD) in order to inform recommendations regarding the access and provision of these services in Ontario. This analysis was one of several analyses undertaken to evaluate interventions for COPD. The perspective of this assessment was that of the Ontario Ministry of Health and Long-Term Care, a provincial payer of medically necessary health care services.
Clinical Need: Condition and Target Population
Canada is facing an increase in chronic respiratory diseases due in part to its aging demographic. The projected increase in COPD will put a strain on health care payers and providers. There is therefore an increasing demand for telehealth services that improve access to health care services while maintaining or improving quality and equality of care. Many telehealth technologies however are in the early stages of development or diffusion and thus require study to define their application and potential harms or benefits. The Medical Advisory Secretariat (MAS) therefore sought to evaluate telehealth technologies for COPD.
Technology
Telemedicine (or telehealth) refers to using advanced information and communication technologies and electronic medical devices to support the delivery of clinical care, professional education, and health-related administrative services.
Generally there are 4 broad functions of home telehealth interventions for COPD:
to monitor vital signs or biological health data (e.g., oxygen saturation),
to monitor symptoms, medication, or other non-biologic endpoints (e.g., exercise adherence),
to provide information (education) and/or other support services (such as reminders to exercise or positive reinforcement), and
to establish a communication link between patient and provider.
These functions often require distinct technologies, although some devices can perform a number of these diverse functions. For the purposes of this review, MAS focused on home telemonitoring and telephone only support technologies.
Telemonitoring (or remote monitoring) refers to the use of medical devices to remotely collect a patient’s vital signs and/or other biologic health data and the transmission of those data to a monitoring station for interpretation by a health care provider.
Telephone only support refers to disease/disorder management support provided by a health care provider to a patient who is at home via telephone or videoconferencing technology in the absence of transmission of patient biologic data.
Research Questions
What is the effectiveness, cost-effectiveness, and safety of home telemonitoring compared with usual care for patients with COPD?
What is the effectiveness, cost-effectiveness, and safety of telephone only support programs compared with usual care for patients with COPD?
Research Methods
Literature Search
Search Strategy
A literature search was performed on November 3, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 2000 until November 3, 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. Articles with unknown eligibility were reviewed with a second clinical epidemiologist, and then a group of epidemiologists until consensus was established. The quality of evidence was assessed as high, moderate, low, or very low according to GRADE methodology.
Inclusion Criteria – Question #1
frequent transmission of a patient’s physiological data collected at home and without a health care professional physically present to health care professionals for routine monitoring through the use of a communication technology;
monitoring combined with a coordinated management and feedback system based on transmitted data;
telemonitoring as a key component of the intervention (subjective determination);
usual care as provided by the usual care provider for the control group;
randomized controlled trials (RCTs), controlled clinical trials (CCTs), systematic reviews, and/or meta-analyses;
published between January 1, 2000 and November 3, 2010.
Inclusion Criteria – Question #2
scheduled or frequent contact between patient and a health care professional via telephone or videoconferencing technology in the absence of transmission of patient physiological data;
monitoring combined with a coordinated management and feedback system based on transmitted data;
telephone support as a key component of the intervention (subjective determination);
usual care as provided by the usual care provider for the control group;
RCTs, CCTs, systematic reviews, and/or meta-analyses;
published between January 1, 2000 and November 3, 2010.
Exclusion Criteria
published in a language other than English;
intervention group (and not control) receiving some form of home visits by a medical professional, typically a nurse (i.e., telenursing) beyond initial technology set-up and education, to collect physiological data, or to somehow manage or treat the patient;
not recording patient or health system outcomes (e.g., technical reports testing accuracy, reliability or other development-related outcomes of a device, acceptability/feasibility studies, etc.);
not using an independent control group that received usual care (e.g., studies employing historical or periodic controls).
Outcomes of Interest
hospitalizations (primary outcome)
mortality
emergency department visits
length of stay
quality of life
other […]
Subgroup Analyses (a priori)
length of intervention (primary)
severity of COPD (primary)
Quality of Evidence
The quality of evidence assigned to individual studies was determined using a modified CONSORT Statement Checklist for Randomized Controlled Trials. (1) The CONSORT Statement was adapted to include 3 additional quality measures: the adequacy of control group description, significant differential loss to follow-up between groups, and greater than or equal to 30% study attrition. Individual study quality was defined based on total scores according to the CONSORT Statement checklist: very low (0 to < 40%), low (≥ 40 to < 60%), moderate (≥ 60 to < 80%), and high (≥ 80 to 100%).
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Six publications, representing 5 independent trials, met the eligibility criteria for Research Question #1. Three trials were RCTs reported across 4 publications, whereby patients were randomized to home telemonitoring or usual care, and 2 trials were CCTs, whereby patients or health care centers were nonrandomly assigned to intervention or usual care.
A total of 310 participants were studied across the 5 included trials. The mean age of study participants in the included trials ranged from 61.2 to 74.5 years for the intervention group and 61.1 to 74.5 years for the usual care group. The percentage of men ranged from 40% to 64% in the intervention group and 46% to 72% in the control group.
All 5 trials were performed in a moderate to severe COPD patient population. Three trials initiated the intervention following discharge from hospital. One trial initiated the intervention following a pulmonary rehabilitation program. The final trial initiated the intervention during management of patients at an outpatient clinic.
Four of the 5 trials included oxygen saturation (i.e., pulse oximetry) as one of the biological patient parameters being monitored. Additional parameters monitored included forced expiratory volume in one second, peak expiratory flow, and temperature.
There was considerable clinical heterogeneity between trials in study design, methods, and intervention/control. In relation to the telemonitoring intervention, 3 of the 5 included studies used an electronic health hub that performed multiple functions beyond the monitoring of biological parameters. One study used only a pulse oximeter device alone with modem capabilities. Finally, in 1 study, patients measured and then forwarded biological data to a nurse during a televideo consultation. Usual care varied considerably between studies.
Only one trial met the eligibility criteria for Research Question #2. The included trial was an RCT that randomized 60 patients to nurse telephone follow-up or usual care (no telephone follow-up). Participants were recruited from the medical department of an acute-care hospital in Hong Kong and began receiving follow-up after discharge from the hospital with a diagnosis of COPD (no severity restriction). The intervention itself consisted of only two 10-to 20-minute telephone calls, once between days 3 to 7 and once between days 14 to 20, involving a structured, individualized educational and supportive programme led by a nurse that focused on 3 components: assessment, management options, and evaluation.
Regarding Research Question #1:
Low to very low quality evidence (according to GRADE) finds non-significant effects or conflicting effects (of significant or non-significant benefit) for all outcomes examined when comparing home telemonitoring to usual care.
There is a trend towards significant increase in time free of hospitalization and use of other health care services with home telemonitoring, but these findings need to be confirmed further in randomized trials of high quality.
There is severe clinical heterogeneity between studies that limits summary conclusions.
The economic impact of home telemonitoring is uncertain and requires further study.
Home telemonitoring is largely dependent on local information technologies, infrastructure, and personnel, and thus the generalizability of external findings may be low. Jurisdictions wishing to replicate home telemonitoring interventions should likely test those interventions within their jurisdictional framework before adoption, or should focus on home-grown interventions that are subjected to appropriate evaluation and proven effective.
Regarding Research Question #2:
Low quality evidence finds significant benefit in favour of telephone-only support for self-efficacy and emergency department visits when compared to usual care, but non-significant results for hospitalizations and hospital length of stay.
There are very serious issues with the generalizability of the evidence and thus additional research is required.
PMCID: PMC3384362  PMID: 23074421
7.  Long-Term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this health technology assessment was to determine the effectiveness, cost-effectiveness, and safety of long-term oxygen therapy (LTOT) for chronic obstructive pulmonary disease (COPD).
Clinical Need: Condition and Target Population
Oxygen therapy is used in patients with COPD with hypoxemia, or very low blood oxygen levels, because they may have difficulty obtaining sufficient oxygen from inspired air.
Technology
Long-term oxygen therapy is extended use of oxygen. Oxygen therapy is delivered as a gas from an oxygen source. Different oxygen sources are: 1) oxygen concentrators, electrical units delivering oxygen converted from room air; 2) liquid oxygen systems, which deliver gaseous oxygen stored as liquid in a tank; and 3) oxygen cylinders, which contain compressed gaseous oxygen. All are available in portable versions. Oxygen is breathed in through a nasal cannula or through a mask covering the mouth and nose. The treating clinician determines the flow rate, duration of use, method of administration, and oxygen source according to individual patient needs. Two landmark randomized controlled trials (RCTs) of patients with COPD established the role of LTOT in COPD. Questions regarding the use of LTOT, however, still remain.
Research Question
What is the effectiveness, cost-effectiveness, and safety of LTOT compared with no LTOT in patients with COPD, who are stratified by severity of hypoxemia?
Research Methods
Literature Search
Search Strategy
A literature search was performed on September 8, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, CINAHL, the Cochrane Library, and INAHTA for studies published from January 1, 2007 to September 8, 2010.
A single clinical epidemiologist reviewed the abstracts, obtained full-text articles for studies meeting the eligibility criteria, and examined reference lists for additional relevant studies not identified through the literature search. A second clinical epidemiologist and then a group of epidemiologists reviewed articles with an unknown eligibility until consensus was established.
Inclusion Criteria
patients with mild, moderate, or severe hypoxemia;
English-language articles published between January 1, 2007 and September 8, 2010;
journal articles reporting on effectiveness, cost-effectiveness, or safety for the comparison of interest;
clearly described study design and methods;
health technology assessments, systematic reviews, RCTs, or prospective cohort observational studies;
any type of observational study for the evaluation of safety.
Exclusion Criteria
no hypoxemia
non-English papers
animal or in vitro studies
case reports, case series, or case-case studies
studies comparing different oxygen therapy regimens
studies on nocturnal oxygen therapy
studies on short-burst, palliative, or ambulatory oxygen (supplemental oxygen during exercise or activities of daily living)
Outcomes of Interest
mortality/survival
hospitalizations
readmissions
forced expiratory volume in 1 second (FEV1)
forced vital capacity (FVC)
FEV1/FVC
pulmonary hypertension
arterial partial pressure of oxygen (PaO2)
arterial partial pressure of carbon dioxide (PaCO2)
end-exercise dyspnea score
endurance time
health-related quality of life
Note: Outcomes of interest were formulated according to existing studies, with arterial pressure of oxygen and carbon dioxide as surrogate outcomes.
Summary of Findings
Conclusions
Based on low quality of evidence, LTOT (~ 15 hours/day) decreases all-cause mortality in patients with COPD who have severe hypoxemia (PaO2 ~ 50 mm Hg) and heart failure.
The effect for all-cause mortality had borderline statistical significance when the control group was no LTOT: one study.
Based on low quality of evidence, there is no beneficial effect of LTOT on all-cause mortality at 3 and 7 years in patients with COPD who have mild-to-moderate hypoxemia (PaO2 ~ 59-65 mm Hg)1
Based on very low quality of evidence, there is some suggestion that LTOT may have a beneficial effect over time on FEV1 and PaCO2 in patients with COPD who have severe hypoxemia and heart failure: improved methods are needed.
Based on very low quality of evidence, there is no beneficial effect of LTOT on lung function or exercise factors in patients with COPD who have mild-to-moderate hypoxemia, whether survivors or nonsurvivors are assessed.
Based on low to very low quality of evidence, LTOT does not prevent readmissions in patients with COPD who have severe hypoxemia. Limited data suggest LTOT increases the risk of hospitalizations.
Limited work has been performed evaluating the safety of LTOT by severity of hypoxemia.
Based on low to very low quality of evidence, LTOT may have a beneficial effect over time on health-related quality of life in patients with COPD who have severe hypoxemia. Limited work using disease-specific instruments has been performed.
Ethical constraints of not providing LTOT to eligible patients with COPD prohibit future studies from examining LTOT outcomes in an ideal way.
PMCID: PMC3384376  PMID: 23074435
8.  Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients with Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this analysis was to compare hospital-at-home care with inpatient hospital care for patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) who present to the emergency department (ED).
Clinical Need: Condition and Target Population
Acute Exacerbations of Chronic Obstructive Pulmonary Disease
Chronic obstructive pulmonary disease is a disease state characterized by airflow limitation that is not fully reversible. This airflow limitation is usually both progressive and associated with an abnormal inflammatory response of the lungs to noxious particles or gases. The natural history of COPD involves periods of acute-onset worsening of symptoms, particularly increased breathlessness, cough, and/or sputum, that go beyond normal day-to-day variations; these are known as acute exacerbations.
Two-thirds of COPD exacerbations are caused by an infection of the tracheobronchial tree or by air pollution; the cause in the remaining cases is unknown. On average, patients with moderate to severe COPD experience 2 or 3 exacerbations each year.
Exacerbations have an important impact on patients and on the health care system. For the patient, exacerbations result in decreased quality of life, potentially permanent losses of lung function, and an increased risk of mortality. For the health care system, exacerbations of COPD are a leading cause of ED visits and hospitalizations, particularly in winter.
Technology
Hospital-at-home programs offer an alternative for patients who present to the ED with an exacerbation of COPD and require hospital admission for their treatment. Hospital-at-home programs provide patients with visits in their home by medical professionals (typically specialist nurses) who monitor the patients, alter patients’ treatment plans if needed, and in some programs, provide additional care such as pulmonary rehabilitation, patient and caregiver education, and smoking cessation counselling.
There are 2 types of hospital-at-home programs: admission avoidance and early discharge hospital-at-home. In the former, admission avoidance hospital-at-home, after patients are assessed in the ED, they are prescribed the necessary medications and additional care needed (e.g., oxygen therapy) and then sent home where they receive regular visits from a medical professional. In early discharge hospital-at-home, after being assessed in the ED, patients are admitted to the hospital where they receive the initial phase of their treatment. These patients are discharged into a hospital-at-home program before the exacerbation has resolved. In both cases, once the exacerbation has resolved, the patient is discharged from the hospital-at-home program and no longer receives visits in his/her home.
In the models that exist to date, hospital-at-home programs differ from other home care programs because they deal with higher acuity patients who require higher acuity care, and because hospitals retain the medical and legal responsibility for patients. Furthermore, patients requiring home care services may require such services for long periods of time or indefinitely, whereas patients in hospital-at-home programs require and receive the services for a short period of time only.
Hospital-at-home care is not appropriate for all patients with acute exacerbations of COPD. Ineligible patients include: those with mild exacerbations that can be managed without admission to hospital; those who require admission to hospital; and those who cannot be safely treated in a hospital-at-home program either for medical reasons and/or because of a lack of, or poor, social support at home.
The proposed possible benefits of hospital-at-home for treatment of exacerbations of COPD include: decreased utilization of health care resources by avoiding hospital admission and/or reducing length of stay in hospital; decreased costs; increased health-related quality of life for patients and caregivers when treated at home; and reduced risk of hospital-acquired infections in this susceptible patient population.
Ontario Context
No hospital-at-home programs for the treatment of acute exacerbations of COPD were identified in Ontario. Patients requiring acute care for their exacerbations are treated in hospitals.
Research Question
What is the effectiveness, cost-effectiveness, and safety of hospital-at-home care compared with inpatient hospital care of acute exacerbations of COPD?
Research Methods
Literature Search
Search Strategy
A literature search was performed on August 5, 2010, using OVID MEDLINE, OVID MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination database for studies published from January 1, 1990, to August 5, 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists and health technology assessment websites were also examined for any additional relevant studies not identified through the systematic search.
Inclusion Criteria
English language full-text reports;
health technology assessments, systematic reviews, meta-analyses, and randomized controlled trials (RCTs);
studies performed exclusively in patients with a diagnosis of COPD or studies including patients with COPD as well as patients with other conditions, if results are reported for COPD patients separately;
studies performed in patients with acute exacerbations of COPD who present to the ED;
studies published between January 1, 1990, and August 5, 2010;
studies comparing hospital-at-home and inpatient hospital care for patients with acute exacerbations of COPD;
studies that include at least 1 of the outcomes of interest (listed below).
Cochrane Collaboration reviews have defined hospital-at-home programs as those that provide patients with active treatment for their acute exacerbation in their home by medical professionals for a limited period of time (in this case, until the resolution of the exacerbation). If a hospital-at-home program had not been available, these patients would have been admitted to hospital for their treatment.
Exclusion Criteria
< 18 years of age
animal studies
duplicate publications
grey literature
Outcomes of Interest
Patient/clinical outcomes
mortality
lung function (forced expiratory volume in 1 second)
health-related quality of life
patient or caregiver preference
patient or caregiver satisfaction with care
complications
Health system outcomes
hospital readmissions
length of stay in hospital and hospital-at-home
ED visits
transfer to long-term care
days to readmission
eligibility for hospital-at-home
Statistical Methods
When possible, results were pooled using Review Manager 5 Version 5.1; otherwise, results were summarized descriptively. Data from RCTs were analyzed using intention-to-treat protocols. In addition, a sensitivity analysis was done assigning all missing data/withdrawals to the event. P values less than 0.05 were considered significant. A priori subgroup analyses were planned for the acuity of hospital-at-home program, type of hospital-at-home program (early discharge or admission avoidance), and severity of the patients’ COPD. Additional subgroup analyses were conducted as needed based on the identified literature. Post hoc sample size calculations were performed using STATA 10.1.
Quality of Evidence
The quality of each included study was assessed, taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Fourteen studies met the inclusion criteria and were included in this review: 1 health technology assessment, 5 systematic reviews, and 7 RCTs.
The following conclusions are based on low to very low quality of evidence. The reviewed evidence was based on RCTs that were inadequately powered to observe differences between hospital-at-home and inpatient hospital care for most outcomes, so there is a strong possibility of type II error. Given the low to very low quality of evidence, these conclusions must be considered with caution.
Approximately 21% to 37% of patients with acute exacerbations of COPD who present to the ED may be eligible for hospital-at-home care.
Of the patients who are eligible for care, some may refuse to participate in hospital-at-home care.
Eligibility for hospital-at-home care may be increased depending on the design of the hospital-at-home program, such as the size of the geographical service area for hospital-at-home and the hours of operation for patient assessment and entry into hospital-at-home.
Hospital-at-home care for acute exacerbations of COPD was associated with a nonsignificant reduction in the risk of mortality and hospital readmissions compared with inpatient hospital care during 2- to 6-month follow-up.
Limited, very low quality evidence suggests that hospital readmissions are delayed in patients who received hospital-at-home care compared with those who received inpatient hospital care (mean additional days before readmission comparing hospital-at-home to inpatient hospital care ranged from 4 to 38 days).
There is insufficient evidence to determine whether hospital-at-home care, compared with inpatient hospital care, is associated with improved lung function.
The majority of studies did not find significant differences between hospital-at-home and inpatient hospital care for a variety of health-related quality of life measures at follow-up. However, follow-up may have been too late to observe an impact of hospital-at-home care on quality of life.
A conclusion about the impact of hospital-at-home care on length of stay for the initial exacerbation (defined as days in hospital or days in hospital plus hospital-at-home care for inpatient hospital and hospital-at-home, respectively) could not be determined because of limited and inconsistent evidence.
Patient and caregiver satisfaction with care is high for both hospital-at-home and inpatient hospital care.
PMCID: PMC3384361  PMID: 23074420
9.  Identifying asthma and chronic obstructive pulmonary disease in patients with persistent cough presenting to general practitioners: descriptive study 
BMJ : British Medical Journal  1998;316(7140):1286-1290.
Objective: To determine the prevalence of asthma and chronic obstructive pulmonary disease in patients not known to have these disorders, who present in general practice with persistent cough, and to ascertain criteria to help general practitioners in diagnosis.
Design: Descriptive study.
Setting: Primary healthcare centre in the Netherlands.
Subjects: 192 patients aged 18-75 years, not known to have asthma or chronic obstructive pulmonary disease, attending their general practitioner with cough persisting for at least 2 weeks.
Methods: A diagnosis of asthma or chronic obstructive pulmonary disease was based on the recurrence of airway symptoms in the past year accompanied by spirometric measurements (including bronchodilator testing) and methacholine provocation tests. A scoring formula to estimate the probability of asthma or chronic obstructive pulmonary disease, based on history and physical examination, was generated by means of logistic regression.
Results: 74 patients (39%) were classified as having asthma, 14 (7%) as having chronic obstructive pulmonary disease. The best formula for predicting asthma or chronic obstructive pulmonary disease used scores for three symptoms: (reported) wheeze, (reported) dyspnoea, and allergen induced symptoms, together with prolonged expiration, pack years of smoking, and female sex. Variables were scored 1 when present and 0 when absent, except for allergen induced symptoms (1.5) and number of pack years of smoking (n/25). With a cut off value of 3 on the scoring formula, 76% of the patients could be classified correctly.
Conclusions: About half of patients with persistent cough who present to a general practitioner have asthma or chronic obstructive pulmonary disease. With a simple formula based on three symptoms and prolonged expiration, pack years of smoking, and female sex, most patients may be identified correctly in general practice.
Key messages Nearly half the patients attending a general practitioner with persistent cough show features of asthma or chronic obstructive pulmonary disease (significant bronchodilator response, airway obstruction, or hyperresponsiveness) Most cases can be identified through history taking and physical examination only The key variables to predict which patients are likely to have asthma or chronic obstructive pulmonary disease are: current wheeze and dyspnoea, symptoms elicited by allergens, prolonged expiration, cumulative smoking, and female sex The scoring formula composed of the key variables may help to determine when it is necessary to perform pulmonary function testing to confirm or reject a diagnosis of asthma or chronic obstructive pulmonary disease
PMCID: PMC28529  PMID: 9554899
10.  Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this evidence-based analysis was to determine the effectiveness and cost-effectiveness of smoking cessation interventions in the management of chronic obstructive pulmonary disease (COPD).
Clinical Need: Condition and Target Population
Tobacco smoking is the main risk factor for COPD. It is estimated that 50% of older smokers develop COPD and more than 80% of COPD-associated morbidity is attributed to tobacco smoking. According to the Canadian Community Health Survey, 38.5% of Ontarians who smoke have COPD. In patients with a significant history of smoking, COPD is usually present with symptoms of progressive dyspnea (shortness of breath), cough, and sputum production. Patients with COPD who smoke have a particularly high level of nicotine dependence, and about 30.4% to 43% of patients with moderate to severe COPD continue to smoke. Despite the severe symptoms that COPD patients suffer, the majority of patients with COPD are unable to quit smoking on their own; each year only about 1% of smokers succeed in quitting on their own initiative.
Technology
Smoking cessation is the process of discontinuing the practice of inhaling a smoked substance. Smoking cessation can help to slow or halt the progression of COPD. Smoking cessation programs mainly target tobacco smoking, but may also encompass other substances that can be difficult to stop smoking due to the development of strong physical addictions or psychological dependencies resulting from their habitual use.
Smoking cessation strategies include both pharmacological and nonpharmacological (behavioural or psychosocial) approaches. The basic components of smoking cessation interventions include simple advice, written self-help materials, individual and group behavioural support, telephone quit lines, nicotine replacement therapy (NRT), and antidepressants. As nicotine addiction is a chronic, relapsing condition that usually requires several attempts to overcome, cessation support is often tailored to individual needs, while recognizing that in general, the more intensive the support, the greater the chance of success. Success at quitting smoking decreases in relation to:
a lack of motivation to quit,
a history of smoking more than a pack of cigarettes a day for more than 10 years,
a lack of social support, such as from family and friends, and
the presence of mental health disorders (such as depression).
Research Question
What are the effectiveness and cost-effectiveness of smoking cessation interventions compared with usual care for patients with COPD?
Research Methods
Literature Search
Search Strategy
A literature search was performed on June 24, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations (1950 to June Week 3 2010), EMBASE (1980 to 2010 Week 24), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Library, and the Centre for Reviews and Dissemination for studies published between 1950 and June 2010. A single reviewer reviewed the abstracts and obtained full-text articles for those studies meeting the eligibility criteria. Reference lists were also examined for any additional relevant studies not identified through the search. Data were extracted using a standardized data abstraction form.
Inclusion Criteria
English-language, full reports from 1950 to week 3 of June, 2010;
either randomized controlled trials (RCTs), systematic reviews and meta-analyses, or non-RCTs with controls;
a proven diagnosis of COPD;
adult patients (≥ 18 years);
a smoking cessation intervention that comprised at least one of the treatment arms;
≥ 6 months’ abstinence as an outcome; and
patients followed for ≥ 6 months.
Exclusion Criteria
case reports
case series
Outcomes of Interest
≥ 6 months’ abstinence
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
Nine RCTs were identified from the literature search. The sample sizes ranged from 74 to 5,887 participants. A total of 8,291 participants were included in the nine studies. The mean age of the patients in the studies ranged from 54 to 64 years. The majority of studies used the Global Initiative for Chronic Obstructive Lung Disease (GOLD) COPD staging criteria to stage the disease in study subjects. Studies included patients with mild COPD (2 studies), mild-moderate COPD (3 studies), moderate–severe COPD (1 study) and severe–very severe COPD (1 study). One study included persons at risk of COPD in addition to those with mild, moderate, or severe COPD, and 1 study did not define the stages of COPD. The individual quality of the studies was high. Smoking cessation interventions varied across studies and included counselling or pharmacotherapy or a combination of both. Two studies were delivered in a hospital setting, whereas the remaining 7 studies were delivered in an outpatient setting. All studies reported a usual care group or a placebo-controlled group (for the drug-only trials). The follow-up periods ranged from 6 months to 5 years. Due to excessive clinical heterogeneity in the interventions, studies were first grouped into categories of similar interventions; statistical pooling was subsequently performed, where appropriate. When possible, pooled estimates using relative risks for abstinence rates with 95% confidence intervals were calculated. The remaining studies were reported separately.
Abstinence Rates
Table ES1 provides a summary of the pooled estimates for abstinence, at longest follow-up, from the trials included in this review. It also shows the respective GRADE qualities of evidence.
Summary of Results*
Abbreviations: CI, confidence interval; NRT, nicotine replacement therapy.
Statistically significant (P < 0.05).
One trial used in this comparison had 2 treatment arms each examining a different antidepressant.
Conclusions
Based on a moderate quality of evidence, compared with usual care, abstinence rates are significantly higher in COPD patients receiving intensive counselling or a combination of intensive counselling and NRT.
Based on limited and moderate quality of evidence, abstinence rates are significantly higher in COPD patients receiving NRT compared with placebo.
Based on a moderate quality of evidence, abstinence rates are significantly higher in COPD patients receiving the antidepressant bupropion compared to placebo.
PMCID: PMC3384371  PMID: 23074432
11.  Elevated cardiovascular risk among adults with obstructive and restrictive airway functioning in the United States: a cross-sectional study of the National Health and Nutrition Examination Survey from 2007–2010 
Respiratory Research  2012;13(1):115.
Background
Reasons for the excess risk for cardiovascular disease among people with chronic obstructive pulmonary disease remain unclear. Our objective was to examine the cardiovascular risk profile for adults with obstructive and restrictive impairments of lung functioning in a representative sample of adults from the United States.
Methods
We used data from adults aged 20–79 years who participated in the National Health and Nutrition Examination Survey from 2007 to 2010 and had a pulmonary function test. The severity of obstructive impairment was defined by adapting the Global Initiative for Chronic Obstructive Lung Disease criteria.
Results
Among 7249 participants, 80.9% had a normal pulmonary function test, 5.7% had a restrictive impairment, 7.9% had mild obstructive impairment, and 5.5% had moderate or severe/very severe obstructive impairment. Participants with obstructive impairment had high rates of smoking and increased serum concentrations of cotinine. Compared to participants with normal pulmonary functioning, participants with at least moderate obstructive impairment had elevated concentrations of C-reactive protein but lower concentrations of total cholesterol and non-high-density lipoprotein cholesterol. Among participants aged 50–74 years, participants with at least a moderate obstructive impairment or a restrictive impairment had an elevated predicted 10-year risk for cardiovascular disease.
Conclusions
The high rates of smoking among adults with impaired pulmonary functioning, particularly those with obstructive impairment, point to a need for aggressive efforts to promote smoking cessation in these adults. In addition, adults with restrictive impairment may require increased attention to and fine-tuning of their cardiovascular risk profile.
doi:10.1186/1465-9921-13-115
PMCID: PMC3546884  PMID: 23237325
Chronic obstructive pulmonary disease; Cardiovascular diseases; Risk factors; Spirometry
12.  Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Objective
The objective of this evidence-based analysis was to examine the effectiveness, safety, and cost-effectiveness of noninvasive positive pressure ventilation (NPPV) in the following patient populations: patients with acute respiratory failure (ARF) due to acute exacerbations of chronic obstructive pulmonary disease (COPD); weaning of COPD patients from invasive mechanical ventilation (IMV); and prevention of or treatment of recurrent respiratory failure in COPD patients after extubation from IMV.
Clinical Need and Target Population
Acute Hypercapnic Respiratory Failure
Respiratory failure occurs when the respiratory system cannot oxygenate the blood and/or remove carbon dioxide from the blood. It can be either acute or chronic and is classified as either hypoxemic (type I) or hypercapnic (type II) respiratory failure. Acute hypercapnic respiratory failure frequently occurs in COPD patients experiencing acute exacerbations of COPD, so this is the focus of this evidence-based analysis. Hypercapnic respiratory failure occurs due to a decrease in the drive to breathe, typically due to increased work to breathe in COPD patients.
Technology
There are several treatment options for ARF. Usual medical care (UMC) attempts to facilitate adequate oxygenation and treat the cause of the exacerbation, and typically consists of supplemental oxygen, and a variety of medications such as bronchodilators, corticosteroids, and antibiotics. The failure rate of UMC is high and has been estimated to occur in 10% to 50% of cases.
The alternative is mechanical ventilation, either invasive or noninvasive. Invasive mechanical ventilation involves sedating the patient, creating an artificial airway through endotracheal intubation, and attaching the patient to a ventilator. While this provides airway protection and direct access to drain sputum, it can lead to substantial morbidity, including tracheal injuries and ventilator-associated pneumonia (VAP).
While both positive and negative pressure noninvasive ventilation exists, noninvasive negative pressure ventilation such as the iron lung is no longer in use in Ontario. Noninvasive positive pressure ventilation provides ventilatory support through a facial or nasal mask and reduces inspiratory work. Noninvasive positive pressure ventilation can often be used intermittently for short periods of time to treat respiratory failure, which allows patients to continue to eat, drink, talk, and participate in their own treatment decisions. In addition, patients do not require sedation, airway defence mechanisms and swallowing functions are maintained, trauma to the trachea and larynx are avoided, and the risk for VAP is reduced. Common complications are damage to facial and nasal skin, higher incidence of gastric distension with aspiration risk, sleeping disorders, and conjunctivitis. In addition, NPPV does not allow direct access to the airway to drain secretions and requires patients to cooperate, and due to potential discomfort, compliance and tolerance may be low.
In addition to treating ARF, NPPV can be used to wean patients from IMV through the gradual removal of ventilation support until the patient can breathe spontaneously. Five to 30% of patients have difficultly weaning. Tapering levels of ventilatory support to wean patients from IMV can be achieved using IMV or NPPV. The use of NPPV helps to reduce the risk of VAP by shortening the time the patient is intubated.
Following extubation from IMV, ARF may recur, leading to extubation failure and the need for reintubation, which has been associated with increased risk of nosocomial pneumonia and mortality. To avoid these complications, NPPV has been proposed to help prevent ARF recurrence and/or to treat respiratory failure when it recurs, thereby preventing the need for reintubation.
Research Questions
What is the effectiveness, cost-effectiveness, and safety of NPPV for the treatment of acute hypercapnic respiratory failure due to acute exacerbations of COPD compared with
usual medical care, and
invasive mechanical ventilation?
What is the effectiveness, cost-effectiveness, and safety of NPPV compared with IMV in COPD patients after IMV for the following purposes:
weaning COPD patients from IMV,
preventing ARF in COPD patients after extubation from IMV, and
treating ARF in COPD patients after extubation from IMV?
Research Methods
Literature Search
A literature search was performed on December 3, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), Wiley Cochrane, and the Centre for Reviews and Dissemination/International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 2004 until December 3, 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search.
Since there were numerous studies that examined the effectiveness of NPPV for the treatment of ARF due to exacerbations of COPD published before 2004, pre-2004 trials which met the inclusion/exclusion criteria for this evidence-based review were identified by hand-searching reference lists of included studies and systematic reviews.
Inclusion Criteria
English language full-reports;
health technology assessments, systematic reviews, meta-analyses, and randomized controlled trials (RCTs);
studies performed exclusively in patients with a diagnosis of COPD or studies performed with patients with a mix of conditions if results are reported for COPD patients separately;
patient population: (Question 1) patients with acute hypercapnic respiratory failure due to an exacerbation of COPD; (Question 2a) COPD patients being weaned from IMV; (Questions 2b and 2c) COPD patients who have been extubated from IMV.
Exclusion Criteria
< 18 years of age
animal studies
duplicate publications
grey literature
studies examining noninvasive negative pressure ventilation
studies comparing modes of ventilation
studies comparing patient-ventilation interfaces
studies examining outcomes not listed below, such as physiologic effects including heart rate, arterial blood gases, and blood pressure
Outcomes of Interest
mortality
intubation rates
length of stay (intensive care unit [ICU] and hospital)
health-related quality of life
breathlessness
duration of mechanical ventilation
weaning failure
complications
NPPV tolerance and compliance
Statistical Methods
When possible, results were pooled using Review Manager 5 Version 5.1, otherwise, the results were summarized descriptively. Dichotomous data were pooled into relative risks using random effects models and continuous data were pooled using weighted mean differences with a random effects model. Analyses using data from RCTs were done using intention-to-treat protocols; P values < 0.05 were considered significant. A priori subgroup analyses were planned for severity of respiratory failure, location of treatment (ICU or hospital ward), and mode of ventilation with additional subgroups as needed based on the literature. Post hoc sample size calculations were performed using STATA 10.1.
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
NPPV for the Treatment of ARF due to Acute Exacerbations of COPD
NPPV Plus Usual Medical Care Versus Usual Medical Care Alone for First Line Treatment
A total of 1,000 participants were included in 11 RCTs1; the sample size ranged from 23 to 342. The mean age of the participants ranged from approximately 60 to 72 years of age. Based on either the Global Initiative for Chronic Obstructive Lung Disease (GOLD) COPD stage criteria or the mean percent predicted forced expiratory volume in 1 second (FEV1), 4 of the studies included people with severe COPD, and there was inadequate information to classify the remaining 7 studies by COPD severity. The severity of the respiratory failure was classified into 4 categories using the study population mean pH level as follows: mild (pH ≥ 7.35), moderate (7.30 ≤ pH < 7.35), severe (7.25 ≤ pH < 7.30), and very severe (pH < 7.25). Based on these categories, 3 studies included patients with a mild respiratory failure, 3 with moderate respiratory failure, 4 with severe respiratory failure, and 1 with very severe respiratory failure.
The studies were conducted either in the ICU (3 of 11 studies) or general or respiratory wards (8 of 11 studies) in hospitals, with patients in the NPPV group receiving bilevel positive airway pressure (BiPAP) ventilatory support, except in 2 studies, which used pressure support ventilation and volume cycled ventilation, respectively. Patients received ventilation through nasal, facial, or oronasal masks. All studies specified a protocol or schedule for NPPV delivery, but this varied substantially across the studies. For example, some studies restricted the amount of ventilation per day (e.g., 6 hours per day) and the number of days it was offered (e.g., maximum of 3 days); whereas, other studies provided patients with ventilation for as long as they could tolerate it and recommended it for much longer periods of time (e.g., 7 to 10 days). These differences are an important source of clinical heterogeneity between the studies. In addition to NPPV, all patients in the NPPV group also received UMC. Usual medical care varied between the studies, but common medications included supplemental oxygen, bronchodilators, corticosteroids, antibiotics, diuretics, and respiratory stimulators.
The individual quality of the studies ranged. Common methodological issues included lack of blinding and allocation concealment, and small sample sizes.
Need for Endotracheal Intubation
Eleven studies reported the need for endotracheal intubation as an outcome. The pooled results showed a significant reduction in the need for endotracheal intubation in the NPPV plus UMC group compared with the UMC alone group (relative risk [RR], 0.38; 95% confidence interval [CI], 0.28−0.50). When subgrouped by severity of respiratory failure, the results remained significant for the mild, severe, and very severe respiratory failure groups.
GRADE: moderate
Inhospital Mortality
Nine studies reported inhospital mortality as an outcome. The pooled results showed a significant reduction in inhospital mortality in the NPPV plus UMC group compared with the UMC group (RR, 0.53; 95% CI, 0.35−0.81). When subgrouped by severity of respiratory failure, the results remained significant for the moderate and severe respiratory failure groups.
GRADE: moderate
Hospital Length of Stay
Eleven studies reported hospital length of stay (LOS) as an outcome. The pooled results showed a significant decrease in the mean length of stay for the NPPV plus UMC group compared with the UMC alone group (weighted mean difference [WMD], −2.68 days; 95% CI, −4.41 to −0.94 days). When subgrouped by severity of respiratory failure, the results remained significant for the mild, severe, and very severe respiratory failure groups.
GRADE: moderate
Complications
Five studies reported complications. Common complications in the NPPV plus UMC group included pneumonia, gastrointestinal disorders or bleeds, skin abrasions, eye irritation, gastric insufflation, and sepsis. Similar complications were observed in the UMC group including pneumonia, sepsis, gastrointestinal disorders or bleeds, pneumothorax, and complicated endotracheal intubations. Many of the more serious complications in both groups occurred in those patients who required endotracheal intubation. Three of the studies compared complications in the NPPV plus UMC and UMC groups. While the data could not be pooled, overall, the NPPV plus UMC group experienced fewer complications than the UMC group.
GRADE: low
Tolerance/Compliance
Eight studies reported patient tolerance or compliance with NPPV as an outcome. NPPV intolerance ranged from 5% to 29%. NPPV tolerance was generally higher for patients with more severe respiratory failure. Compliance with the NPPV protocol was reported by 2 studies, which showed compliance decreases over time, even over short periods such as 3 days.
NPPV Versus IMV for the Treatment of Patients Who Failed Usual Medical Care
A total of 205 participants were included in 2 studies; the sample sizes of these studies were 49 and 156. The mean age of the patients was 71 to 73 years of age in 1 study, and the median age was 54 to 58 years of age in the second study. Based on either the GOLD COPD stage criteria or the mean percent predicted FEV1, patients in 1 study had very severe COPD. The COPD severity could not be classified in the second study. Both studies had study populations with a mean pH less than 7.23, which was classified as very severe respiratory failure in this analysis. One study enrolled patients with ARF due to acute exacerbations of COPD who had failed medical therapy. The patient population was not clearly defined in the second study, and it was not clear whether they had to have failed medical therapy before entry into the study.
Both studies were conducted in the ICU. Patients in the NPPV group received BiPAP ventilatory support through nasal or full facial masks. Patients in the IMV group received pressure support ventilation.
Common methodological issues included small sample size, lack of blinding, and unclear methods of randomization and allocation concealment. Due to the uncertainty about whether both studies included the same patient population and substantial differences in the direction and significance of the results, the results of the studies were not pooled.
Mortality
Both studies reported ICU mortality. Neither study showed a significant difference in ICU mortality between the NPPV and IMV groups, but 1 study showed a higher mortality rate in the NPPV group (21.7% vs. 11.5%) while the other study showed a lower mortality rate in the NPPV group (5.1% vs. 6.4%). One study reported 1-year mortality and showed a nonsignificant reduction in mortality in the NPPV group compared with the IMV group (26.1% vs. 46.1%).
GRADE: low to very low
Intensive Care Unit Length of Stay
Both studies reported LOS in the ICU. The results were inconsistent. One study showed a statistically significant shorter LOS in the NPPV group compared with the IMV group (5 ± 1.35 days vs. 9.29 ± 3 days; P < 0.001); whereas, the other study showed a nonsignificantly longer LOS in the NPPV group compared with the IMV group (22 ± 19 days vs. 21 ± 20 days; P = 0.86).
GRADE: very low
Duration of Mechanical Ventilation
Both studies reported the duration of mechanical ventilation (including both invasive and noninvasive ventilation). The results were inconsistent. One study showed a statistically significant shorter duration of mechanical ventilation in the NPPV group compared with the IMV group (3.92 ± 1.08 days vs. 7.17 ± 2.22 days; P < 0.001); whereas, the other study showed a nonsignificantly longer duration of mechanical ventilation in the NPPV group compared with the IMV group (16 ± 19 days vs. 15 ± 21 days; P = 0.86). GRADE: very low
Complications
Both studies reported ventilator-associated pneumonia and tracheotomies. Both showed a reduction in ventilator-associated pneumonia in the NPPV group compared with the IMV group, but the results were only significant in 1 study (13% vs. 34.6%, P = 0.07; and 6.4% vs. 37.2%, P < 0.001, respectively). Similarly, both studies showed a reduction in tracheotomies in the NPPV group compared with the IMV group, but the results were only significant in 1 study (13% vs. 23.1%, P = 0.29; and 6.4% vs. 34.6%; P < 0.001).
GRADE: very low
Other Outcomes
One of the studies followed patients for 12 months. At the end of follow-up, patients in the NPPV group had a significantly lower rate of needing de novo oxygen supplementation at home. In addition, the IMV group experienced significant increases in functional limitations due to COPD, while no increase was seen in the NPPV group. Finally, no significant differences were observed for hospital readmissions, ICU readmissions, and patients with an open tracheotomy, between the NPPV and IMV groups.
NPPV for Weaning COPD Patients From IMV
A total of 80 participants were included in the 2 RCTs; the sample sizes of the studies were 30 and 50 patients. The mean age of the participants ranged from 58 to 69 years of age. Based on either the GOLD COPD stage criteria or the mean percent predicted FEV1, both studies included patients with very severe COPD. Both studies also included patients with very severe respiratory failure (mean pH of the study populations was less than 7.23). Chronic obstructive pulmonary disease patients receiving IMV were enrolled in the study if they failed a T-piece weaning trial (spontaneous breathing test), so they could not be directly extubated from IMV.
Both studies were conducted in the ICU. Patients in the NPPV group received weaning using either BiPAP or pressure support ventilation NPPV through a face mask, and patients in the IMV weaning group received pressure support ventilation. In both cases, weaning was achieved by tapering the ventilation level.
The individual quality of the studies ranged. Common methodological problems included unclear randomization methods and allocation concealment, lack of blinding, and small sample size.
Mortality
Both studies reported mortality as an outcome. The pooled results showed a significant reduction in ICU mortality in the NPPV group compared with the IMV group (RR, 0.47; 95% CI, 0.23−0.97; P = 0.04).
GRADE: moderate
Intensive Care Unit Length of Stay
Both studies reported ICU LOS as an outcome. The pooled results showed a nonsignificant reduction in ICU LOS in the NPPV group compared with the IMV group (WMD, −5.21 days; 95% CI, −11.60 to 1.18 days).
GRADE: low
Duration of Mechanical Ventilation
Both studies reported duration of mechanical ventilation (including both invasive and noninvasive ventilation) as an outcome. The pooled results showed a nonsignificant reduction in duration of mechanical ventilation (WMD, −3.55 days; 95% CI, −8.55 to 1.44 days).
GRADE: low
Nosocomial Pneumonia
Both studies reported nosocominal pneumonia as an outcome. The pooled results showed a significant reduction in nosocomial pneumonia in the NPPV group compared with the IMV group (RR, 0.14; 95% CI, 0.03−0.71; P = 0.02).
GRADE: moderate
Weaning Failure
One study reported a significant reduction in weaning failure in the NPPV group compared with the IMV group, but the results were not reported in the publication. In this study, 1 of 25 patients in the NPPV group and 2 of 25 patients in the IMV group could not be weaned after 60 days in the ICU.
NPPV After Extubation of COPD Patients From IMV
The literature was reviewed to identify studies examining the effectiveness of NPPV compared with UMC in preventing recurrence of ARF after extubation from IMV or treating acute ARF which has recurred after extubation from IMV. No studies that included only COPD patients or reported results for COPD patients separately were identified for the prevention of ARF postextubation.
One study was identified for the treatment of ARF in COPD patients that recurred within 48 hours of extubation from IMV. This study included 221 patients, of whom 23 had COPD. A post hoc subgroup analysis was conducted examining the rate of reintubation in the COPD patients only. A nonsignificant reduction in the rate of reintubation was observed in the NPPV group compared with the UMC group (7 of 14 patients vs. 6 of 9 patients, P = 0.67). GRADE: low
Conclusions
NPPV Plus UMC Versus UMC Alone for First Line Treatment of ARF due to Acute Exacerbations of COPD
Moderate quality of evidence showed that compared with UMC, NPPV plus UMC significantly reduced the need for endotracheal intubation, inhospital mortality, and the mean length of hospital stay.
Low quality of evidence showed a lower rate of complications in the NPPV plus UMC group compared with the UMC group.
NPPV Versus IMV for the Treatment of ARF in Patients Who Have Failed UMC
Due to inconsistent and low to very low quality of evidence, there was insufficient evidence to draw conclusions on the comparison of NPPV versus IMV for patients who failed UMC.
NPPV for Weaning COPD Patients From IMV
Moderate quality of evidence showed that weaning COPD patients from IMV using NPPV results in significant reductions in mortality, nosocomial pneumonia, and weaning failure compared with weaning with IMV.
Low quality of evidence showed a nonsignificant reduction in the mean LOS and mean duration of mechanical ventilation in the NPPV group compared with the IMV group.
NPPV for the Treatment of ARF in COPD Patients After Extubation From IMV
Low quality of evidence showed a nonsignificant reduction in the rate of reintubation in the NPPV group compared with the UMC group; however, there was inadequate evidence to draw conclusions on the effectiveness of NPPV for the treatment of ARF in COPD patients after extubation from IMV
PMCID: PMC3384377  PMID: 23074436
13.  Pulmonary Function in HIV-Infected Recreational Drug Users in the Era of Anti-Retroviral Therapy 
Background
Individuals with HIV infection commonly have pulmonary function abnormalities, including airflow obstruction and diffusion impairment, which may be more prevalent among recreational drug users. To date, the relationship between drug use and pulmonary function abnormalities among those with HIV remains unclear.
Objective
To determine associations between recreational drug use and airflow obstruction, diffusion impairment, and radiographic emphysema in men and women with HIV.
Methods
Cross-sectional analysis of pulmonary function and self-reported recreational drug use data from a cohort of 121 men and 63 women with HIV. Primary outcomes were the presence (yes/no) of: 1) airflow obstruction, (pre- or post-bronchodilator forced expiratory volume in 1 second/forced vital capacity<0.70); 2) moderate diffusion impairment (diffusing capacity for carbon monoxide <60% predicted); and 3) radiographic emphysema (>1% of lung voxels <−950 Hounsfield units). Exposures of interest were frequency of recreational drug use, recent (since last study visit) drug use, and any lifetime drug use. We used logistic regression to determine associations between recreational drug use and the primary outcomes.
Results
HIV-infected men and women reported recent recreational drug use at 56.0% and 31.0% of their study visits, respectively, and 48.8% of men and 39.7% of women reported drug use since their last study visit. Drug use was not associated with airway obstruction or radiographic emphysema in men or women. Recent crack cocaine use was independently associated with moderate diffusion impairment in women (odds ratio 17.6; 95% confidence interval 1.3–249.6, p=0.03).
Conclusions
In this cross-sectional analysis, we found that recreational drug use was common among HIV-infected men and women and recent crack cocaine use was associated with moderate diffusion impairment in women. Given the increasing prevalence of HIV infection, any relationship between drug use and prevalence or severity of chronic pulmonary diseases could have a significant impact on HIV and chronic disease management.
doi:10.4172/2155-6113.1000365
PMCID: PMC4318265  PMID: 25664201
HIV; COPD; Emphysema; Diffusion impairment; Drug use; Pulmonary function; Cocaine
14.  Lung Function and Incidence of Chronic Obstructive Pulmonary Disease after Improved Cooking Fuels and Kitchen Ventilation: A 9-Year Prospective Cohort Study 
PLoS Medicine  2014;11(3):e1001621.
Pixin Ran, Nanshan Zhong, and colleagues report that cleaner cooking fuels and improved ventilation were associated with better lung function and reduced COPD among a cohort of villagers in Southern China.
Please see later in the article for the Editors' Summary
Background
Biomass smoke is associated with the risk of chronic obstructive pulmonary disease (COPD), but few studies have elaborated approaches to reduce the risk of COPD from biomass burning. The purpose of this study was to determine whether improved cooking fuels and ventilation have effects on pulmonary function and the incidence of COPD.
Methods and Findings
A 9-y prospective cohort study was conducted among 996 eligible participants aged at least 40 y from November 1, 2002, through November 30, 2011, in 12 villages in southern China. Interventions were implemented starting in 2002 to improve kitchen ventilation (by providing support and instruction for improving biomass stoves or installing exhaust fans) and to promote the use of clean fuels (i.e., biogas) instead of biomass for cooking (by providing support and instruction for installing household biogas digesters); questionnaire interviews and spirometry tests were performed in 2005, 2008, and 2011. That the interventions improved air quality was confirmed via measurements of indoor air pollutants (i.e., SO2, CO, CO2, NO2, and particulate matter with an aerodynamic diameter of 10 µm or less) in a randomly selected subset of the participants' homes. Annual declines in lung function and COPD incidence were compared between those who took up one, both, or neither of the interventions.
Use of clean fuels and improved ventilation were associated with a reduced decline in forced expiratory volume in 1 s (FEV1): decline in FEV1 was reduced by 12 ml/y (95% CI, 4 to 20 ml/y) and 13 ml/y (95% CI, 4 to 23 ml/y) in those who used clean fuels and improved ventilation, respectively, compared to those who took up neither intervention, after adjustment for confounders. The combined improvements of use of clean fuels and improved ventilation had the greatest favorable effects on the decline in FEV1, with a slowing of 16 ml/y (95% CI, 9 to 23 ml/y). The longer the duration of improved fuel use and ventilation, the greater the benefits in slowing the decline of FEV1 (p<0.05). The reduction in the risk of COPD was unequivocal after the fuel and ventilation improvements, with an odds ratio of 0.28 (95% CI, 0.11 to 0.73) for both improvements.
Conclusions
Replacing biomass with biogas for cooking and improving kitchen ventilation are associated with a reduced decline in FEV1 and risk of COPD.
Trial Registration
Chinese Clinical Trial Register ChiCTR-OCH-12002398
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Nearly 3 billion people in developing countries heat their homes and cook by burning biomass—wood, crop waste, and animal dung—in open fires and leaky stoves. Burning biomass this way releases pollutants into the home that impair lung function and that are responsible for more than a million deaths from chronic obstructive pulmonary disease (COPD) every year. COPD is a group of diseases that interfere with breathing. Normally, air is breathed in through the nose or mouth and travels down the windpipe into two bronchial tubes (airways) in the lungs. These tubes branch into smaller tubes (bronchioles) that end in bunches of tiny air sacs (alveoli). Oxygen in the air passes through the thin walls of these sacs into small blood vessels and is taken to the heart for circulation round the body. The two main types of COPD—chronic bronchitis (long-term irritation and swelling of the bronchial tubes) and emphysema (damage to the walls of the alveoli)—make it hard for people to breathe. Most people with COPD have both chronic bronchitis and emphysema, both of which are caused by long-term exposure to cigarette smoke, indoor air pollution, and other lung irritants. Symptoms of COPD include breathlessness during exercise and a persistent cough that produces large amounts of phlegm (mucus). There is no cure for COPD, but drugs and oxygen therapy can relieve its symptoms, and avoiding lung irritants can slow disease progression.
Why Was This Study Done?
Exposure to indoor air pollution has been associated with impaired lung function and COPD in several studies. However, few studies have assessed the long-term effects on lung function and on the incidence of COPD (the proportion of a population that develops COPD each year) of replacing biomass with biogas (a clean fuel produced by bacterial digestion of biodegradable materials) for cooking and heating, or of improving kitchen ventilation during cooking. Here, the researchers undertook a nine-year prospective cohort study in rural southern China to investigate whether these interventions are associated with any effects on lung function and on the incidence of COPD. A prospective cohort study enrolls a group of people, determines their characteristics at baseline, and follows them over time to see whether specific characteristic are associated with specific outcomes.
What Did the Researchers Do and Find?
The researchers offered nearly 1,000 people living in 12 villages in southern China access to biogas and to improved kitchen ventilation. All the participants, who adopted these interventions according to personal preferences, completed a questionnaire about their smoking habits and occupational exposure to pollutants and had their lung function measured using a spirometry test at the start and end of the study. Some participants also completed a questionnaire and had their lung function measured three and six years into the study. Finally, the researchers measured levels of indoor air pollution in a randomly selected subset of homes at the end of the study to confirm that the interventions had reduced indoor air pollution. Compared with non-use, the use of clean fuels and of improved ventilation were both associated with a reduction in the decline in lung function over time after adjusting for known characteristics that affect lung function, such as smoking. The use of both interventions reduced the decline in lung function more markedly than either intervention alone, and the benefits of using the interventions increased with length of use. Notably, the combined use of both interventions reduced the risk of COPD occurrence among the study participants.
What Do These Findings Mean?
These findings suggest that, among people living in rural southern China, the combined interventions of use of biogas instead of biomass and improved kitchen ventilation were associated with a reduced decline in lung function over time and with a reduced risk of COPD. Because participants were not randomly allocated to intervention groups, the people who adopted the interventions may have shared other unknown characteristics (confounders) that affected their lung function (for example, having a healthier lifestyle). Thus, it is not possible to conclude that either intervention actually caused a reduction in the decline in lung function. Nevertheless, these findings suggest that the use of biogas as a substitute for biomass for cooking and heating and improvements in kitchen ventilation might lead to a reduction in the global burden of COPD associated with biomass smoke.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001621.
The US National Heart, Lung, and Blood Institute provides detailed information for the public about COPD
The US Centers for Disease Control and Prevention provides information about COPD and links to other resources (in English and Spanish)
The UK National Health Service Choices website provides information for patients and carers about COPD, personal stories, and links to other resources
The British Lung Foundation, a not-for-profit organization, provides information about COPD in several languages
The Global Initiative for Chronic Obstructive Lung Disease works to improve prevention and treatment of COPD around the world
The World Health Organization provides information about all aspects of indoor air pollution and health (in English, French, and Spanish)
MedlinePlus provides links to other information about COPD (in English and Spanish)
doi:10.1371/journal.pmed.1001621
PMCID: PMC3965383  PMID: 24667834
15.  Can inhaled fluticasone alone or in combination with salmeterol reduce systemic inflammation in chronic obstructive pulmonary disease? – study protocol for a randomized controlled trial [NCT00120978] 
Background
Systemic inflammation is associated with various complications in chronic obstructive pulmonary disease including weight loss, cachexia, osteoporosis, cancer and cardiovascular diseases. Inhaled corticosteroids attenuate airway inflammation, reduce exacerbations, and improve mortality in chronic obstructive pulmonary disease. Whether inhaled corticosteroids by themselves or in combination with a long-acting β2-adrenoceptor agonist repress systemic inflammation in chronic obstructive pulmonary disease is unknown. The Advair Biomarkers in COPD (ABC) study will determine whether the effects of inhaled corticosteroids alone or in combination with a long-acting β2-adrenoceptor agonist reduce systemic inflammation and improve health status in patients with chronic obstructive pulmonary disease.
Methods/Design
After a 4-week run-in phase during which patients with stable chronic obstructive pulmonary disease will receive inhaled fluticasone (500 micrograms twice daily), followed by a 4-week withdrawal phase during which all inhaled corticosteroids and long acting β2-adrenoceptor agonists will be discontinued, patients will be randomized to receive fluticasone (500 micrograms twice daily), fluticasone/salmeterol combination (500/50 micrograms twice daily), or placebo for four weeks. The study will recruit 250 patients across 11 centers in western Canada. Patients must be 40 years of age or older with at least 10 pack-year smoking history and have chronic obstructive pulmonary disease defined as forced expiratory volume in one second to vital capacity ratio of 0.70 or less and forced expiratory volume in one second that is 80% of predicted or less. Patients will be excluded if they have any known chronic systemic infections, inflammatory conditions, history of previous solid organ transplantation, myocardial infarction, or cerebrovascular accident within the past 3 months prior to study enrolment. The primary end-point is serum C-reactive protein level. Secondary end-points include circulating inflammatory cytokines such as interleukin-6 and interleukin-8 as well as health-related quality of life and lung function.
Discussion
If inhaled corticosteroids by themselves or in combination with a long-acting β2-adrenoceptor agonist could repress systemic inflammation, they might greatly improve clinical prognosis by reducing various complications in chronic obstructive pulmonary disease.
doi:10.1186/1471-2466-6-3
PMCID: PMC1373664  PMID: 16460562
16.  Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease (COPD) Using an Ontario Policy Model 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at: http://www.hqontario.ca/en/mas/mas_ohtas_mn.html.
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-Term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at: http://fhs.mcmaster.ca/ceb/faculty_member_giacomini.htm.
For more information on the economic analysis, please visit the PATH website: http://www.path-hta.ca/About-Us/Contact-Us.aspx.
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website: http://theta.utoronto.ca/static/contact.
Background
Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation throughout the airways, parenchyma, and pulmonary vasculature. The inflammation causes repeated cycles of injury and repair in the airway wall— inflammatory cells release a variety of chemicals and lead to cellular damage. The inflammation process also contributes to the loss of elastic recoil pressure in the lung, thereby reducing the driving pressure for expiratory flow through narrowed and poorly supported airways, in which airflow resistance is significantly increased. Expiratory flow limitation is the pathophysiological hallmark of COPD.
Exacerbations of COPD contribute considerably to morbidity and mortality, and impose a burden on the health care system. They are a leading cause of emergency room visits and hospitalizations, particularly in the winter. In Canada, the reported average cost for treating a moderate exacerbation is $641; for a major exacerbation, the cost is $10,086.
Objective
The objective of this study was to evaluate the cost-effectiveness and budget impact of the following interventions in moderate to very severe COPD, investigated in the Medical Advisory Secretariat Chronic Obstructive Pulmonary Disease Mega-Analysis Series:
smoking cessation programs in moderate COPD in an outpatient setting:
– intensive counselling (IC) versus usual care (UC)
– nicotine replacement therapy (NRT) versus UC
– IC + NRT versus placebo
– bupropion versus placebo
multidisciplinary care (MDC) teams versus UC in moderate to severe COPD in an outpatient setting
pulmonary rehabilitation (PR) versus UC following acute exacerbations in moderate to severe COPD
long-term oxygen therapy (LTOT) versus UC in severe hypoxemia in COPD in an outpatient setting
ventilation:
– noninvasive positive pressure ventilation (NPPV) + usual medical care versus usual medical care in acute respiratory failure due to an acute exacerbation in severe COPD in an inpatient setting
– weaning with NPPV versus weaning with invasive mechanical ventilation in acute respiratory failure due to an acute exacerbation in very severe COPD in an inpatient setting
Methods
A cost-utility analysis was conducted using a Markov probabilistic model. The model consists of different health states based on the Global Initiative for Chronic Obstructive Lung Disease COPD severity classification. Patients were assigned different costs and utilities depending on their severity health state during each model cycle. In addition to moving between health states, patients were at risk of acute exacerbations of COPD in each model cycle. During each cycle, patients could have no acute exacerbation, a minor acute exacerbation, or a major exacerbation. For the purposes of the model, a major exacerbation was defined as one that required hospitalization. Patients were assigned different costs and utilities in each model cycle, depending on whether they experienced an exacerbation, and its severity.
Starting cohorts reflected the various patient populations from the trials analyzed. Incremental cost-effectiveness ratios (ICERs)—that is, costs per quality-adjusted life-year (QALY)—were estimated for each intervention using clinical parameters and summary estimates of relative risks of (re)hospitalization, as well as mortality and abstinence rates, from the COPD mega-analysis evidence-based analyses.
A budget impact analysis was also conducted to project incremental costs already being incurred or resources already in use in Ontario. Using provincial data, medical literature, and expert opinion, health system impacts were calculated for the strategies investigated.
All costs are reported in Canadian dollars.
Results
All smoking cessation programs were dominant (i.e., less expensive and more effective overall). Assuming a base case cost of $1,041 and $1,527 per patient for MDC and PR, the ICER was calculated to be $14,123 per QALY and $17,938 per QALY, respectively. When the costs of MDC and PR were varied in a 1-way sensitivity analysis to reflect variation in resource utilization reported in the literature, the ICER increased to $55,322 per QALY and $56,270 per QALY, respectively. Assuming a base case cost of $2,261 per year per patient for LTOT as reported by data from the Ontario provincial program, the ICER was calculated to be $38,993 per QALY. Ventilation strategies were dominant (i.e., cheaper and more effective), as reflected by the clinical evidence of significant in-hospital days avoided in the study group.
Ontario currently pays for IC through physician billing (translating to a current burden of $8 million) and bupropion through the Ontario Drug Benefit program (translating to a current burden of almost $2 million). The burden of NRT was projected to be $10 million, with future expenditures of up to $1 million in Years 1 to 3 for incident cases.
Ontario currently pays for some chronic disease management programs. Based on the most recent Family Health Team data, the costs of MDC programs to manage COPD were estimated at $85 million in fiscal year 2010, with projected future expenditures of up to $51 million for incident cases, assuming the base case cost of the program. However, this estimate does not accurately reflect the current costs to the province because of lack of report by Family Health Teams, lack of capture of programs outside this model of care by any data set in the province, and because the resource utilization and frequency of visits/follow-up phone calls were based on the findings in the literature rather than the actual Family Health Team COPD management programs in place in Ontario. Therefore, MDC resources being utilized in the province are unknown and difficult to measure.
Data on COPD-related hospitalizations were pulled from Ontario administrative data sets and based on consultation with experts. Half of hospitalized patients will access PR resources at least once, and half of these will repeat the therapy, translating to a potential burden of $17 million to $32 million, depending on the cost of the program. These resources are currently being absorbed, but since utilization is not being captured by any data set in the province, it is difficult to quantify and estimate. Provincial programs may be under-resourced, and patients may not be accessing these services effectively.
Data from the LTOT provincial program (based on fiscal year 2006 information) suggested that the burden was $65 million, with potential expenditures of up to $0.2 million in Years 1 to 3 for incident cases.
From the clinical evidence on ventilation (i.e., reduction in length of stay in hospital), there were potential cost savings to the hospitals of $42 million and $12 million for NPPV and weaning with NPPV, respectively, if the study intervention were adopted. Future cost savings were projected to be up to $4 million and $1 million, respectively, for incident cases.
Conclusions
Currently, costs for most of these interventions are being absorbed by provider services, the Ontario Drug Benefit Program, the Assistive Devices Program, and the hospital global budget. The most cost-effective intervention for COPD will depend on decision-makers’ willingness to pay. Lack of provincial data sets capturing resource utilization for the various interventions poses a challenge for estimating current burden and future expenditures.
PMCID: PMC3384363  PMID: 23074422
17.  Relationships Between Airflow Obstruction and Quantitative CT Measurements of Emphysema, Air Trapping, and Airways in Subjects With and Without Chronic Obstructive Pulmonary Disease 
AJR. American journal of roentgenology  2013;201(3):W460-W470.
OBJECTIVE
This study evaluates the relationships between quantitative CT (QCT) and spirometric measurements of disease severity in cigarette smokers with and without chronic obstructive pulmonary disease (COPD).
MATERIALS AND METHODS
Inspiratory and expiratory CT scans of 4062 subjects in the Genetic Epidemiology of COPD (COPDGene) Study were evaluated. Measures examined included emphysema, defined as the percentage of low-attenuation areas ≤ −950 HU on inspiratory CT, which we refer to as “LAA-950I”; air trapping, defined as the percentage of low-attenuation areas ≤ −856 HU on expiratory CT, which we refer to as “LAA-856E”; and the inner diameter, inner and outer areas, wall area, airway wall thickness, and square root of the wall area of a hypothetical airway of 10-mm internal perimeter of segmental and subsegmental airways. Correlations were determined between spirometry and several QCT measures using statistics software (SAS, version 9.2).
RESULTS
QCT measurements of low-attenuation areas correlate strongly and significantly (p < 0.0001) with spirometry. The correlation between LAA-856E and forced expiratory volume in 1 second (FEV1) and the ratio of FEV1 to forced vital capacity (FVC) (r = −0.77 and −0.84, respectively) is stronger than the correlation between LAA-950I and FEV1 and FEV1/FVC (r = −0.67 and r = −0.76). Inspiratory and expiratory volume changes decreased with increasing disease severity, as measured by the Global Initiative for Chronic Obstructive Pulmonary Disease (GOLD) staging system (p < 0.0001). When airway variables were included with low-attenuation area measures in a multiple regression model, the model accounted for a statistically greater proportion of variation in FEV1 and FEV1/FVC (R2 = 0.72 and 0.77, respectively). Airway measurements alone are less correlated with spirometric measures of FEV1 (r = 0.15 to −0.44) and FEV1/FVC (r = 0.19 to −0.34).
CONCLUSION
QCT measurements are strongly associated with spirometric results showing impairment in smokers. LAA-856E strongly correlates with physiologic measurements of airway obstruction. Airway measurements can be used concurrently with QCT measures of low-attenuation areas to accurately predict lung function.
doi:10.2214/AJR.12.10102
PMCID: PMC4067052  PMID: 23971478
air trapping; airway measurements; chronic obstructive pulmonary disease; emphysema; quantitative CT
18.  CFTR Regulates Early Pathogenesis of Chronic Obstructive Lung Disease in βENaC-Overexpressing Mice 
PLoS ONE  2012;7(8):e44059.
Background
Factors determining the onset and severity of chronic obstructive pulmonary disease remain poorly understood. Previous studies demonstrated that airway surface dehydration in βENaC-overexpressing (βENaC-Tg) mice on a mixed genetic background caused either neonatal mortality or chronic obstructive lung disease suggesting that the onset of lung disease was modulated by the genetic background.
Methods
To test this hypothesis, we backcrossed βENaC-Tg mice onto two inbred strains (C57BL/6 and BALB/c) and studied effects of the genetic background on neonatal mortality, airway ion transport and airway morphology. Further, we crossed βENaC-Tg mice with CFTR-deficient mice to validate the role of CFTR in early lung disease.
Results
We demonstrate that the C57BL/6 background conferred increased CFTR-mediated Cl− secretion, which was associated with decreased mucus plugging and mortality in neonatal βENaC-Tg C57BL/6 compared to βENaC-Tg BALB/c mice. Conversely, genetic deletion of CFTR increased early mucus obstruction and mortality in βENaC-Tg mice.
Conclusions
We conclude that a decrease or absence of CFTR function in airway epithelia aggravates the severity of early airway mucus obstruction and related mortality in βENaC-Tg mice. These results suggest that genetic or environmental factors that reduce CFTR activity may contribute to the onset and severity of chronic obstructive pulmonary disease and that CFTR may serve as a novel therapeutic target.
doi:10.1371/journal.pone.0044059
PMCID: PMC3427321  PMID: 22937152
19.  Causal and Synthetic Associations of Variants in the SERPINA Gene Cluster with Alpha1-antitrypsin Serum Levels 
PLoS Genetics  2013;9(8):e1003585.
Several infrequent genetic polymorphisms in the SERPINA1 gene are known to substantially reduce concentration of alpha1-antitrypsin (AAT) in the blood. Since low AAT serum levels fail to protect pulmonary tissue from enzymatic degradation, these polymorphisms also increase the risk for early onset chronic obstructive pulmonary disease (COPD). The role of more common SERPINA1 single nucleotide polymorphisms (SNPs) in respiratory health remains poorly understood.
We present here an agnostic investigation of genetic determinants of circulating AAT levels in a general population sample by performing a genome-wide association study (GWAS) in 1392 individuals of the SAPALDIA cohort.
Five common SNPs, defined by showing minor allele frequencies (MAFs) >5%, reached genome-wide significance, all located in the SERPINA gene cluster at 14q32.13. The top-ranking genotyped SNP rs4905179 was associated with an estimated effect of β = −0.068 g/L per minor allele (P = 1.20*10−12). But denser SERPINA1 locus genotyping in 5569 participants with subsequent stepwise conditional analysis, as well as exon-sequencing in a subsample (N = 410), suggested that AAT serum level is causally determined at this locus by rare (MAF<1%) and low-frequent (MAF 1–5%) variants only, in particular by the well-documented protein inhibitor S and Z (PI S, PI Z) variants. Replication of the association of rs4905179 with AAT serum levels in the Copenhagen City Heart Study (N = 8273) was successful (P<0.0001), as was the replication of its synthetic nature (the effect disappeared after adjusting for PI S and Z, P = 0.57). Extending the analysis to lung function revealed a more complex situation. Only in individuals with severely compromised pulmonary health (N = 397), associations of common SNPs at this locus with lung function were driven by rarer PI S or Z variants. Overall, our meta-analysis of lung function in ever-smokers does not support a functional role of common SNPs in the SERPINA gene cluster in the general population.
Author Summary
Low levels of alpha1-antitrypsin (AAT) in the blood are a well-established risk factor for accelerated loss in lung function and chronic obstructive pulmonary disease. While a few infrequent genetic polymorphisms are known to influence the serum levels of this enzyme, the role of common genetic variants has not been examined so far. The present genome-wide scan for associated variants in approximately 1400 Swiss inhabitants revealed a chromosomal locus containing the functionally established variants of AAT deficiency and variants previously associated with lung function and emphysema. We used dense genotyping of this genetic region in more than 5500 individuals and subsequent conditional analyses to unravel which of these associated variants contribute independently to the phenotype's variability. All associations of common variants could be attributed to the rarer functionally established variants, a result which was then replicated in an independent population-based Danish cohort. Hence, this locus represents a textbook example of how a large part of a trait's heritability can be hidden in infrequent genetic polymorphisms. The attempt to transfer these results to lung function furthermore suggests that effects of common variants in this genetic region in ever-smokers may also be explained by rarer variants, but only in individuals with hampered pulmonary health.
doi:10.1371/journal.pgen.1003585
PMCID: PMC3749935  PMID: 23990791
20.  Diesel Exhaust Particle Exposure In Vitro Alters Monocyte Differentiation and Function 
PLoS ONE  2012;7(12):e51107.
Air pollution by diesel exhaust particles is associated with elevated mortality and increased hospital admissions in individuals with respiratory diseases such as asthma and chronic obstructive pulmonary disease. During active inflammation monocytes are recruited to the airways and can replace resident alveolar macrophages. We therefore investigated whether chronic fourteen day exposure to low concentrations of diesel exhaust particles can alter the phenotype and function of monocytes from healthy individuals and those with chronic obstructive pulmonary disease. Monocytes were purified from the blood of healthy individuals and people with a diagnosis of chronic obstructive pulmonary disease. Monocyte-derived macrophages were generated in the presence or absence of diesel exhaust particles and their phenotypes studied through investigation of their lifespan, cytokine generation in response to Toll like receptor agonists and heat killed bacteria, and expression of surface markers. Chronic fourteen day exposure of monocyte-derived macrophages to concentrations of diesel exhaust particles >10 µg/ml caused mitochondrial and lysosomal dysfunction, and a gradual loss of cells over time both in healthy and chronic obstructive pulmonary disease individuals. Chronic exposure to lower concentrations of diesel exhaust particles impaired CXCL8 cytokine responses to lipopolysaccharide and heat killed E. coli, and this phenotype was associated with a reduction in CD14 and CD11b expression. Chronic diesel exhaust particle exposure may therefore alter both numbers and function of lung macrophages differentiating from locally recruited monocytes in the lungs of healthy people and patients with chronic obstructive pulmonary disease.
doi:10.1371/journal.pone.0051107
PMCID: PMC3517601  PMID: 23236439
21.  Left ventricular function in patients with chronic obstructive pulmonary disease 
Journal of Clinical Investigation  1968;47(5):1143-1153.
Left ventricular function was assessed in six patients with essentially normal cardiopulmonary function, in five patients with primary myocardial disease, and in 16 patients with chronic obstructive pulmonary disease by determining the response of the ventricle to an increased resistance to ejection. Studies were performed at the time of cardiac catheterization and increased resistance to left ventricular ejection was produced by the intravenous infusion of methoxamine.
In the control patients, methoxamine produced an increase in stroke volume index (SVI), in stroke work index (SWI), and stroke power index (SPI), whereas left ventricular end-diastolic pressure (LVEDP) increased only moderately. In contrast SVI, SWI, and SPI fell, whereas LVEDP increased inordinately in the patients with myocardiopathy. The patients with chronic obstructive pulmonary disease responded to the infusion with an increase in SVI, SWI, SPI, and LVEDP comparable to the control patients. Furthermore, in this latter group of patients, a quantitatively similar response was observed in those with essentially normal resting hemodynamics, in those with resting pulmonary hypertension, and in those whose disease had progressed to the stage of right ventricular failure.
This study provides no evidence that chronic obstructive pulmonary disease results in chronic impairment of left ventricular function, but on the contrary, has demonstrated that the left ventricle responds normally to an increased pressure load in these patients.
PMCID: PMC297266  PMID: 5645859
22.  Effect of high flow oxygen on mortality in chronic obstructive pulmonary disease patients in prehospital setting: randomised controlled trial 
Objectives To compare standard high flow oxygen treatment with titrated oxygen treatment for patients with an acute exacerbation of chronic obstructive pulmonary disease in the prehospital setting.
Design Cluster randomised controlled parallel group trial.
Setting Ambulance service in Hobart, Tasmania, Australia.
Participants 405 patients with a presumed acute exacerbation of chronic obstructive pulmonary disease who were treated by paramedics, transported, and admitted to the Royal Hobart Hospital during the trial period; 214 had a diagnosis of chronic obstructive pulmonary disease confirmed by lung function tests in the previous five years.
Interventions High flow oxygen treatment compared with titrated oxygen treatment in the prehospital (ambulance/paramedic) setting.
Main outcome measure Prehospital or in-hospital mortality.
Results In an intention to treat analysis, the risk of death was significantly lower in the titrated oxygen arm compared with the high flow oxygen arm for all patients (high flow oxygen n=226; titrated oxygen n=179) and for the subgroup of patients with confirmed chronic obstructive pulmonary disease (high flow n=117; titrated n=97). Overall mortality was 9% (21 deaths) in the high flow oxygen arm compared with 4% (7 deaths) in the titrated oxygen arm; mortality in the subgroup with confirmed chronic obstructive pulmonary disease was 9% (11 deaths) in the high flow arm compared with 2% (2 deaths) in the titrated oxygen arm. Titrated oxygen treatment reduced mortality compared with high flow oxygen by 58% for all patients (relative risk 0.42, 95% confidence interval 0.20 to 0.89; P=0.02) and by 78% for the patients with confirmed chronic obstructive pulmonary disease (0.22, 0.05 to 0.91; P=0.04). Patients with chronic obstructive pulmonary disease who received titrated oxygen according to the protocol were significantly less likely to have respiratory acidosis (mean difference in pH 0.12 (SE 0.05); P=0.01; n=28) or hypercapnia (mean difference in arterial carbon dioxide pressure −33.6 (16.3) mm Hg; P=0.02; n=29) than were patients who received high flow oxygen.
Conclusions Titrated oxygen treatment significantly reduced mortality, hypercapnia, and respiratory acidosis compared with high flow oxygen in acute exacerbations of chronic obstructive pulmonary disease. These results provide strong evidence to recommend the routine use of titrated oxygen treatment in patients with breathlessness and a history or clinical likelihood of chronic obstructive pulmonary disease in the prehospital setting.
Trial registration Australian New Zealand Clinical Trials Register ACTRN12609000236291.
doi:10.1136/bmj.c5462
PMCID: PMC2957540  PMID: 20959284
23.  The pathogenesis of COPD and IPF: Distinct horns of the same devil? 
Respiratory Research  2012;13(1):3.
New paradigms have been recently proposed in the pathogenesis of both chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF), evidencing surprising similarities between these deadly diseases, despite their obvious clinical, radiological and pathologic differences. There is growing evidence supporting a "double hit" pathogenic model where in both COPD and IPF the cumulative action of an accelerated senescence of pulmonary parenchyma (determined by either telomere dysfunction and/or a variety of genetic predisposing factors), and the noxious activity of cigarette smoke-induced oxidative damage are able to severely compromise the regenerative potential of two pulmonary precursor cell compartments (alveolar epithelial precursors in IPF, mesenchymal precursor cells in COPD/emphysema). The consequent divergent derangement of signalling pathways involved in lung tissue renewal (mainly Wnt and Notch), can eventually lead to the distinct abnormal tissue remodelling and functional impairment that characterise the alveolar parenchyma in these diseases (irreversible fibrosis and bronchiolar honeycombing in IPF, emphysema and airway chronic inflammation in COPD).
doi:10.1186/1465-9921-13-3
PMCID: PMC3282644  PMID: 22235752
COPD; IPF; precursor cell senescence; telomere dysfunction; Wnt; Notch; Caveolin-1
24.  Cardiopulmonary response to oxygen therapy in hypoxaemic chronic airflow obstruction. 
Thorax  1989;44(11):930-936.
The acute change in pulmonary artery pressure in response to oxygen may have prognostic value for patients with chronic obstructive pulmonary disease treated with long term domiciliary oxygen. A study was carried out to elucidate the mechanism of the acute cardio-respiratory response to oxygen in such patients and to determine whether it can be quantified non-invasively. The effects of acute oxygen administration (100% for 20 minutes and 28% oxygen for 24 hours) were assessed by non-invasive means and right heart catheterisation in 17 patients with severe stable hypoxaemic chronic obstructive pulmonary disease. Measurements included change in the ratio of dead space to tidal volume (VD/VT), effective pulmonary capillary blood flow (by rebreathing and single breath soluble gas uptake: QRB, QSB), left ventricular ejection fraction (radionuclide ventriculography), and M mode echocardiographic estimates of ventricular diameters and fractional shortening. These values were compared with those obtained from right heart catheter measurements of pulmonary artery pressure, cardiac index (thermodilution and direct carbon dioxide Fick: QTD, QFICK), and pulmonary vascular resistance. Oxygen administration resulted in a significant fall in pulmonary artery pressure, QTD, and QRB and a significant increase in VD/VT. The fall in QRB after 100% oxygen breathing for 20 minutes correlated strongly with the fall in pulmonary artery pressure (r = 0.86). There was no correlation between the fall in pulmonary artery pressure and the fall in QSB or the risen in VD/VT. Left ventricular ejection fraction did not change significantly. Echocardiography was technically unsatisfactory because of lung hyperinflation. Apart from a possible relation between VO2max and fall in pulmonary artery pressure after 24 hours of 28% oxygen breathing (r = 0.49, p less than 0.1) none of the baseline respiratory function measurements predicted the fall in pulmonary artery pressure or QRB. It is concluded that the cardiopulmonary response to acute oxygen breathing in patients with hypoxic chronic obstructive pulmonary disease includes a reduction in pulmonary artery pressure and cardiac output and a redistribution of pulmonary blood flow, and that rebreathing measurements of effective pulmonary blood flow can be used to quantify this response non-invasively.
PMCID: PMC462150  PMID: 2595634
25.  Effect of Co-existing Chronic Obstructive Pulmonary Disease and Cognitive Impairment on Health Outcomes in Older Adults 
Objectives
To determine the extent to which the co-occurrence of chronic obstructive pulmonary disease (COPD) and cognitive impairment affect adverse health outcomes in older adults.
Design
Multi-center longitudinal cohort study.
Setting
California, Pennsylvania, Maryland, and North Carolina.
Participants
Three thousand ninety-three community-dwelling adults aged ≥65 from the Cardiovascular Health Study. Four hundred thirty-one participants had chronic obstructive pulmonary disease (COPD) at study baseline.
Measurements
Follow-up began at the second CHS visit and continued for three years. Spirometric criteria for airflow limitation served to establish COPD, using the Lambda-Mu-Sigma method, which accounts for age-related changes in lung function. Cognitive impairment was evaluated by the modified Mini Mental State Exam and claims data. Outcomes were respiratory-related and all-cause hospitalizations and death.
Results
Participants with co-existing COPD and cognitive impairment had the highest rates of respiratory-related (adjusted hazard ratio [HR]=4.10, 95%CI=1.86–9.05) and all-cause hospitalizations (HR= 1.34, 95%CI=1.00–1.80) and death (HR=2.29, 95%CI=1.18–4.45). In particular, individuals with both conditions had a 48% higher rate of all-cause hospitalizations (adjusted synergy index [SI]=1.48, 95%CI=0.19–11.31) and nearly a three-fold higher rate of death (SI=2.74, 95%CI=0.43–17.32) than the sum of risks for each respective outcome associated with having COPD or cognitive impairment alone. However, tests for interaction were not statistically significant for the presence of synergism between both conditions relative to any of the outcomes. Therefore, we cannot conclude that the combined effect of COPD and cognitive impairment is greater than additive.
Conclusion
Co-existing COPD and cognitive impairment have an additive effect on respiratory-related and all-cause hospitalizations and death. Optimizing outcomes in older adults with COPD and cognitive impairment will require that we determine how to improve concurrent management of both conditions.
doi:10.1111/j.1532-5415.2012.04171.x
PMCID: PMC3470752  PMID: 23035917
Chronic obstructive pulmonary disease; cognitive impairment; health outcomes; hospitalizations; disability; death

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