Aerobic exercise can improve cardiovascular fitness and does not seem to be detrimental to patients with asthma, though its role in changing asthma control and inflammatory profiles is unclear. The main hypothesis of the current randomised controlled trial is that aerobic exercise will be superior to usual care in improving asthma control. Key secondary outcomes are asthma quality of life and inflammatory profiles.
A total of 104 sedentary adults with physician-diagnosed asthma will be recruited. Eligible participants will undergo a series of baseline assessments including: the asthma control questionnaire; the asthma quality-of-life questionnaire and the inflammatory profile (assessed from both the blood and sputum samples). On completion of the assessments, participants will be randomised (1:1 allocation) to either 12-weeks of usual care or usual care plus aerobic exercise. Aerobic exercise will consist of three supervised training sessions per week. Each session will consist of taking a short-acting bronchodilator, 10 min of warm-up, 40 min of aerobic exercise (50–75% of heart rate reserve for weeks 1–4, then 70–85% for weeks 5–12) and a 10 min cool-down. Within 1 week of completion, participants will be reassessed (same battery as at baseline). Analyses will assess the difference between the two intervention arms on postintervention levels of asthma control, quality of life and inflammation, adjusting for age, baseline inhaled corticosteroid prescription, body weight change and pretreatment dependent variable level. Missing data will be handled using standard multiple imputation techniques.
Ethics and dissemination
The study has been approved by all relevant research ethics boards. Written consent will be obtained from all participants who will be able to withdraw at any time.
The result will be disseminated to three groups of stakeholder groups: (1) the scientific and professional community; (2) the research participants and (3) the general public.
Registration Details ClinicalTrials.gov Identifier
Exercise; Quality of life; Inflammation
To develop and validate the accuracy of a predictive model to identify adult asthmatics from administrative health care databases.
An existing electronic medical record project in Montreal, Quebec.
One thousand four hundred and thirty-one patients with confirmed asthma status were identified from primary care physician's electronic medical record.
Data Collection/Extraction Methods
Therapeutic indication of asthma in an electronic prescription and/or confirmed asthma from an automated problem list were used as the gold standard. Five groups of asthma-specific markers were identified from administrative health care databases to estimate the probability of the presence of asthma. Cross-validation evaluated the diagnostic ability of each predictive model using 50 percent of sample.
The best performance in discriminating between the patients with asthma and those without it included indicators from medical service and prescription claims databases. The best-fitting algorithm had a sensitivity of 70 percent, a specificity of 94 percent, and positive predictive value of 65 percent. The prescriptions claims–specific algorithm demonstrated a nearly equal performance to the model with medical services and prescription claims combined.
Our algorithm using asthma-specific markers from administrative claims databases provided moderate sensitivity and high specificity.
Asthma/epidemiology; algorithms; databases; health services; medical record system; computerized
Although administrative health care databases have long been used to evaluate adverse drug effects, responses to drug safety signals have been slow and uncoordinated. We describe the establishment of the Canadian Network for Observational Drug Effect Studies (CNODES), a collaborating centre of the Drug Safety and Effectiveness Network (DSEN). CNODES is a distributed network of investigators and linked databases in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec and Nova Scotia. Principles of operation are as follows: (1) research questions are prioritized by the coordinating office of DSEN; (2) the linked data stay within the provinces; (3) for each question, a study team formulates a detailed protocol enabling consistent analyses in each province; (4) analyses are “blind” to results obtained elsewhere; (5) protocol deviations are permitted for technical reasons only; (6) analyses using multivariable methods are lodged centrally with a methods team, which is responsible for combining the results to provide a summary estimate of effect. These procedures are designed to achieve high internal validity of risk estimates and to eliminate the possibility of selective reporting of analyses or outcomes. The value of a coordinated multi-provincial approach is illustrated by projects studying acute renal injury with high-potency statins, community-acquired pneumonia with proton pump inhibitors, and hyperglycemic emergencies with antipsychotic drugs. CNODES is an academically based distributed network of Canadian researchers and data centres with a commitment to rapid and sophisticated analysis of emerging drug safety signals in study populations totalling over 40 million.
Patients with Parkinson's disease have an elevated risk of pneumonia and randomized trials suggest that this risk may be increased with the dopamine agonist pramipexole. It is uncertain whether pramipexole or other dopamine agonists increase the risk of pneumonia.
We used the United Kingdom's General Practice Research Database (GPRD) to identify users of anti-parkinsonian drugs, 40–89 years of age, between 1997 and 2009. Using a nested case–control approach, all incident cases hospitalised for pneumonia were matched with up to ten controls selected among the cohort members. Rate ratios (RR) and 95% confidence intervals (CI) of pneumonia associated with current use of dopamine agonists were estimated using conditional logistic regression, adjusted for covariates.
The cohort included 13,183 users of anti-parkinsonian drugs, with 1,835 newly diagnosed with pneumonia during follow-up (rate 40.9 per 1,000 per year). The rate of pneumonia was not increased with the current use of pramipexole (RR 0.76; 95% CI: 0.57-1.02), compared with no use. The use of pramipexole was not associated with an increased rate of pneumonia when compared with all other dopamine agonists collectively (RR 0.85; 95% CI: 0.62-1.17).
The use of pramipexole does not appear to increase the risk of pneumonia.
Anti-parkinsonian drugs; Drug safety; Parkinson's disease; Restless leg syndrome; Observational study
Little is known concerning risk factors for herpes zoster in the general population. We hypothesised that inhaled corticosteroids (ICS) are a risk factor for herpes zoster especially among users of inhibitors of cytochrome P450 enzymes involved in their metabolism.
We identified a cohort of adult users of respiratory medications in the General Practice Research Database and carried out a nested case control analysis of inhaled corticosteroid use among 8900 new cases of herpes zoster and 88032 controls matching on age and calendar time.
The adjusted odds ratio for the relationship between current use of ICS and the occurrence of herpes zoster was 1.00 (95% confidence interval (CI), 0.94-1.07). There was no increase in risk of herpes zoster even at higher ICS doses; odds ratio 1.05 (95% CI, 0.96-1.14). Among subjects with concomitant prescriptions for an ICS and an inhibitor of cytochrome P450 3A4, the point estimate for the association between herpes zoster and the use of higher doses of inhaled corticosteroids was 1.23 (95% CI, 0.81-1.88).
The use of inhaled corticosteroids, even at high doses and in conjunction with inhibitors of their metabolism, was not a significant risk factor for the occurrence of herpes zoster in adults.
herpes zoster; inhaled corticosteroids; adverse drug effects; observational studies; cytochrome P450
Asthma is a prevalent and costly disease resulting in reduced quality of life for a large proportion of individuals. Effective patient self-management is critical for improving health outcomes. However, key aspects of self-management such as self-monitoring of behaviours and symptoms, coupled with regular feedback from the health care team, are rarely addressed or integrated into ongoing care. Health information technology (HIT) provides unique opportunities to facilitate this by providing a means for two way communication and exchange of information between the patient and care team, and access to their health information, presented in personalized ways that can alert them when there is a need for action. The objective of this study is to evaluate the acceptability and efficacy of using a web-based self-management system, My Asthma Portal (MAP), linked to a case-management system on asthma control, and asthma health-related quality of life.
The trial is a parallel multi-centered 2-arm pilot randomized controlled trial. Participants are randomly assigned to one of two conditions: a) MAP and usual care; or b) usual care alone. Individuals will be included if they are between 18 and 70, have a confirmed asthma diagnosis, and their asthma is classified as not well controlled by their physician. Asthma control will be evaluated by calculating the amount of fast acting beta agonists recorded as dispensed in the provincial drug database, and asthma quality of life using the Mini Asthma Related Quality of Life Questionnaire. Power calculations indicated a needed total sample size of 80 subjects. Data are collected at baseline, 3, 6, and 9 months post randomization. Recruitment started in March 2010 and the inclusion of patients in the trial in June 2010.
Self-management support from the care team is critical for improving chronic disease outcomes. Given the high volume of patients and time constraints during clinical visits, primary care physicians have limited time to teach and reinforce use of proven self-management strategies. HIT has the potential to provide clinicians and a large number of patients with tools to support health behaviour change.
Current Controlled Trials ISRCTN34326236.
Most asthma patients prescribed maintenance asthma therapies still experience periods of asthma worsenings characterized by daytime or nighttime symptoms, or an increased need for rescue medication. In fact, these episodes are highly prevalent even in patients with well-controlled disease. Published literature suggests that asthma worsenings likely represent a window of opportunity during which patients could intervene early to prevent exacerbations or further deterioration of asthma symptoms. However, current evidence suggests that most patients fail to respond or to self-manage appropriately during these periods.
To address the issue of asthma worsenings, an interdisciplinary committee of respirologists, allergists, family physicians, pharmacists and certified asthma educators from across Canada developed a practical definition of asthma worsenings and provided approaches to the prevention and management of these episodes based on current literature. To date, combination inhaled corticosteroid/long-acting beta-agonist therapy, particularly single inhaler maintenance and reliever therapy, appears to be an effective strategy for preventing asthma worsenings and exacerbations. Addressing the potential barriers to appropriate patient self-management of asthma worsenings, such as failure to adequately identify and respond to worsenings, low expectations for controlling asthma, low health literacy and poor patient-health care professional communication, are also critical to the successful prevention and management of these episodes. Finally, an interdisciplinary team approach involving patients and their families, certified asthma educators, primary care physicians, pharmacists and specialists is likely to have the greatest impact on the identification, prevention and management of asthma worsenings.
Asthma worsenings; Education; Exacerbations; Inhaled corticosteroids; Long-acting beta-agonists
Airflow obstruction is relatively uncommon in young adults, and may indicate potential for the development of progressive disease. The objective of the present study was to enumerate and characterize airflow obstruction in a random sample of Canadians aged 20 to 44 years.
The sample (n=2962) was drawn from six Canadian sites.
A prevalence study using the European Community Respiratory Health Survey protocol was conducted. Airflow obstruction was assessed by spirometry. Bronchial responsiveness, skin reactivity to allergens and total serum immunoglobulin E were also measured. Logistic regression was used for analysis.
Airflow obstruction was observed in 6.4% of the sample, not associated with sex or age. The risk of airflow obstruction increased in patients who had smoked and in patients who had lung trouble during childhood. Adjusted for smoking, the risk of airflow obstruction was elevated for subjects with past and current asthma, skin reactivity to allergens, elevated levels of total immunoglobulin E and bronchial hyper-responsiveness. Of the subjects with airflow obstruction, 21% were smokers with a history of asthma, 50% were smokers without asthma, 12% were nonsmokers with asthma and 17% were nonsmokers with no history of asthma. Bronchial hyper-responsiveness increased the prevalence of airflow obstruction in each of these groups.
Smoking and asthma, jointly and individually, are major determinants of obstructive disorders in young adults. Bronchial hyper-responsiveness contributes to obstruction in both groups.
Airway obstruction; Obstructive lung disease; Risk factors; Young adults
Asthma and obesity are frequently associated, and obesity has been considered a factor contributing to both an increase in severity of asthma and to its development. The present document summarizes the proceedings of a symposium held in Montreal, Quebec, on November 2, 2006, under the auspices of the Réseau en santé respiratoire du Fonds de la recherche en santé du Québec in collaboration with the McGill University – Strauss Severe Asthma Program, Université Laval (Quebec City) and Université de Montréal. It includes an overview of the various aspects of the relationships between asthma and obesity with regard to animal models; genetic, hormonal and physiological determinants; influence of comorbidities (eg, sleep apnea syndrome); epidemiology; clinical and psychological features; and management of asthma in the obese population.
Airway inflammation; Asthma; Body mass index; Lung function; Obesity; Sleep apnea syndrome
The primary objective of asthma management is to help patients establish and maintain optimal disease control. Simple and efficient tools are needed to assess patient-reported symptoms so that they can be used with or without airway function to evaluate asthma control.
The objective of the present study was to evaluate the validity of The 30 Second Asthma Test (GlaxoSmithKline Inc, Canada), based on the Canadian Asthma Guidelines, by estimating its relationship with criterion measures of control.
The discriminative and diagnostic validity of The 30 Second Asthma Test™ was examined in a sample of 81 patients with a confirmed diagnosis of asthma. Based on a cut-off score of two or greater on The 30 Second Asthma Test™, the overall agreement with specialist ratings was 65%, and 58% with per cent predicted forced expiratory volume in 1 s. The 30 Second Asthma Test™ scores distinguished between groups of patients who were classified based on the change in intensity of therapy.
The results support the use of The 30 Second Asthma Test™ as a brief screening tool for asthma control.
Asthma; Outcome; Patient management; Patient reported questionnaire; Screening
Given the limited efficacy of oral corticosteroids in treating chronic obstructive pulmonary disease (COPD), the possible cardiac side effects of oral corticosteroids are of particular concern in an elderly population. The impact of the use of oral corticosteroids on the risk of acute myocardial infarction (AMI) in a cohort of patients with COPD was studied.
The Saskatchewan health services databases were used to form a population-based cohort of 5648 patients aged 55 years or older who received a first treatment for COPD between 1990 and 1997. A nested case-control analysis was conducted: 371 cases presenting with a first myocardial infarction were matched with 1864 controls according to the length of follow-up, the date of cohort entry and age. Conditional logistic regression was used to adjust for sex, severity of COPD, systemic hypertension, diabetes and prior cardiovascular disease.
Only the current use of corticosteroids was associated with an increased risk of AMI (adjusted RR=2.01 [95% CI 1.13 to 3.58]), particularly when the current dose was larger than 25 mg/day of prednisone or the equivalent (adjusted RR=3.22 [95% CI 1.42 to 7.34]). This observed increase in risk rapidly returned to baseline after the cessation of the medication, suggesting that the use of such high doses reflected the treatment of acute exacerbations of the disease.
An association was found between the current use of oral corticosteroids and the occurrence of an AMI, suggesting that acute exacerbations of COPD are associated with an increased risk of acute coronary syndromes.
Adverse effects; Cohort studies; COPD; Glucocorticoids; Myocardial infarction
The present supplement summarizes the proceedings of the symposium “Implementing practice guidelines: A workshop on guidelines dissemination and implementation with a focus on asthma and COPD”, which took place in Quebec City, Quebec, from April 14 to 16, 2005. This international symposium was a joint initiative of the Laval University Office of Continuing Medical Education (Bureau de la Formation Médicale Continue), the Canadian Thoracic Society and the Canadian Network for Asthma Care, and was supported by many other organizations and by industrial partners. The objectives of this meeting were to examine the optimal implementation of practice guidelines, review current initiatives for the implementation of asthma and chronic obstructive pulmonary disease (COPD) guidelines in Canada and in the rest of the world, and develop an optimal strategy for future guideline implementation. An impressive group of scientists, physicians and other health care providers, as well as policy makers and representatives of patients’ associations, the pharmaceutical industry, research and health networks, and communications specialists, conveyed their perspectives on how to achieve these goals.
This important event provided a unique opportunity for all participants to discuss key issues in improving the care of patients with asthma and COPD. These two diseases are responsible for an enormous human and socioeconomic burden around the world. Many reports have indicated that current evidence-based guidelines are underused by physicians and others, and that there are many barriers to an effective translation of recommendations into day-to-day care. There is therefore a need to develop more effective ways to communicate key information to both caregivers and patients, and to promote appropriate health behaviours. This symposium contributed to the initiation of what could become the “Canadian Asthma and COPD Campaign”, aimed at improving care and, hence, the quality of life of those suffering from these diseases.
It is hoped that this event will be followed by other meetings that focus on how to improve the transfer of key recommendations from evidence-based guidelines into current care, and how to stimulate research to accomplish this.
Asthma; COPD; Evidence-based medicine; Guidelines implementation; Practice guidelines
Although guidelines for the diagnosis and management of asthma have been published over the last 15 years, there has been little focus on issues relating to asthma in childhood. Since the last revision of the 1999 Canadian asthma consensus report, important new studies, particularly in children, have highlighted the need to incorporate this new information into asthma guidelines.
To review the literature on asthma published between January 2000 and June 2003 and to evaluate the influence of new evidence on the recommendations made in the Canadian Asthma Consensus Report, 1999 and its 2001 update with a major focus on pediatric issues.
Diagnosis of asthma in young children, prevention strategies, pharmacotherapy, inhalation devices, immunotherapy and asthma education were selected for review by small expert resource groups. In June 2003, the reviews were discussed at a meeting under the auspices of the Canadian Network For Asthma Care and the Canadian Thoracic Society. Data published up to December 2004 were subsequently reviewed by the individual expert resource groups.
This report evaluates early life prevention strategies and focuses on treatment of asthma in children. Emphasis is placed on the importance of an early diagnosis and prevention therapy, the benefits of additional therapy and the essential role of asthma education.
We generally support previous recommendations and focus on new issues, particularly those relevant to children and their families. This guide for asthma management is based on the best available published data and the opinion of health care professionals including asthma experts and educators.
The factors that cause children to become smokers in adolescence remain unclear. Although parental smoking and peer pressure may play a role, physiological factors such as lung volume have also been identified.
To investigate these and other possible childhood predictors of teenage smoking, we gathered follow-up data on 191 Montréal schoolchildren, aged 5–12 years (average 9.2 yr) when first examined. At an average age of 13.0 years, they answered further questions on their health and smoking behaviour and provided a second set of spirometric measurements.
At the second survey, 80% of the children had entered high school and 44% had become smokers. Reaching puberty between the surveys was the most significant determinant of becoming a smoker: 56.4% of the 124 children postpubertal at the second survey had taken up smoking, versus 17.9% of the 67 who were still prepubertal (p = 0.001). We found salivary cotinine level, a measure of uptake of environmental tobacco smoke, to be an independent predictor of becoming a teenage smoker; even after adjustment for sex, socioeconomic status of parents, a crowding index, and the numbers at home of siblings, adult smokers and cigarettes smoked, it remained significant for both groups: postpubertal (odds ratio [OR] 1.2, 95% confidence interval [CI] 1.2–3.0) and prepubertal (OR 2.1, 95% CI 1.0– 4.5). The influence of forced vital capacity was marginally significant only in the postpubertal group (OR 5.0, 95% CI 0.88–28.3).
The proportion of nicotine absorbed from that available in environmental tobacco smoke during childhood is associated with subsequent smoking in adolescence. The more efficient absorption of nicotine seen in some children may be related to physiological factors such as lung capacity.
Reported prevalence rates of asthma vary within and between countries around the world. These differences suggest environmental factors in addition to genetic factors in the cause of the disease and may provide clues for preventive strategies. We examined the variability of asthma-related symptoms and medication use among adults in 6 sites across Canada (Vancouver, Winnipeg, Hamilton, Montreal, Halifax and Prince Edward Island) and compared our findings with those from sites that had participated in a recent European survey.
We used the same sampling strategy and standardized questionnaire as those used in the European Community Respiratory Health Survey (ECRHS). The 6 Canadian sites were selected to represent different environments with respect to climate, air pollution and occupational exposure. Community-based samples of 3000 to 4000 people aged 20–44 years were randomly selected in each site. Subjects were asked to complete the questionnaire by mail between March 1993 and November 1994. Prevalence rates (and 95% confidence intervals [CIs]) of asthma symptoms, self-reported asthma attacks and use of asthma medication were compared across the Canadian sites and with sites that had participated in the ECRHS.
The overall response rate of those selected to receive the questionnaire was 86.5% (range 74.5%–92.8%). The prevalence rates of most asthma symptoms varied significantly among the Canadian sites. For instance, 21.9% (Montreal) to 30.4% (Halifax) of the men and 24.0% (Vancouver) to 35.2% (Halifax) of the women reported wheezing in the year before the survey. Depending on the site, 4.4% to 6.3% of the men and 5.2% to 9.5% of the women reported an asthma attack in the last year, and 4.0% to 6.1% of the men and 4.9% to 9.7% of the women were currently using asthma medication. Prevalence rates of symptoms, asthma attacks and medication use did not change with age, but they were higher among women than among men. Compared with the results from the ECRHS sites, those from the Canadian sites were among the highest.
Significant variation in the prevalence of asthma symptoms, asthma attacks and use of asthma medication between Canadian sites and international sites suggests environmental influences. Different combinations of factors in different sites may be responsible for the high prevalence rates and should be the subject of further research to guide clinical management and public health intervention.
The long-term natural history of chronic obstructive pulmonary disease (COPD) in terms of successive severe exacerbations and mortality is unknown.
The authors formed an inception cohort of patients from their first ever hospitalisation for COPD during 1990–2005, using the healthcare databases from the province of Quebec, Canada. Patients were followed until death or 31 March 2007, and all COPD hospitalisations occurring during follow-up were identified. The hazard functions of successive hospitalised COPD exacerbations and all-cause mortality over time were estimated, and HRs adjusted for age, sex, calendar time and comorbidity.
The cohort included 73 106 patients hospitalised for the first time for COPD, of whom 50 580 died during the 17-year follow-up, with 50% and 75% mortality at 3.6 and 7.7 years respectively. The median time from the first to the second hospitalised exacerbation was around 5 years and decreased to <4 months from the 9th to the 10th. The risk of the subsequent severe exacerbation was increased threefold after the second severe exacerbation and 24-fold after the 10th, relative to the first. Mortality after a severe exacerbation peaked to 40 deaths per 10 000 per day in the first week after admission, dropping gradually to 5 after 3 months.
The course of COPD involves a rapid decline in health status after the second severe exacerbation and high mortality in the weeks following every severe exacerbation. Two strategic targets for COPD management should include delaying the second severe exacerbation and improving treatment of severe exacerbations to reduce their excessive early mortality.
Asthma epidemiology; clinical epidemiology; COPD epidemiology; asthma; pulmonary embolism