Published guidelines recommend spirometry to accurately diagnose chronic obstructive pulmonary disease (COPD). However, even spirometry-based COPD prevalence estimates can vary widely. We compared properties of several spirometry-based COPD definitions using data from the international Burden of Obstructive Lung Disease (BOLD)study.
14 sites recruited population-based samples of adults aged ≥40 yrs. Procedures included standardised questionnaires and post-bronchodilator spirometry. 10,001 individuals provided usable data.
Use of the lower limit of normal (LLN) forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio reduced the age-related increases in COPD prevalence that are seen among healthy never-smokers when using the fixed ratio criterion (FEV1/FVC <0.7) recommended by the Global Initiative for Chronic Obstructive Lung Disease. The added requirement of an FEV1 either <80% predicted or below the LLN further reduced age-related increases and also led to the least site-to-site variability in prevalence estimates after adjusting for potential confounders. Use of the FEV1/FEV6 ratio in place of the FEV1/FVC yielded similar prevalence estimates.
Use of the FEV1/FVC
Adult; chronic obstructive pulmonary disease; epidemiology
Background:Metabolic syndrome (Mets) is reportedly associated with chronic obstructive pulmonary disease (COPD). However, the relationship between abdominal circumference (AC) and decline in FEV1 has not been elucidated. We aimed to investigate this relationship among male current smokers.
Methods:Spirometry was performed on subjects (n = 3,257) ≥ 40 years of age, who participated in a community-based annual health check in Takahata, Japan, from 2004 through 2006 (visit 1). Spirometry was re-evaluated, and AC was assessed in 147 of the male current smokers in 2009 (visit 2). The diagnosis of Mets was based on the criteria used in the Hisayama Study.
Results:No significant relationships were observed between AC and spirometric parameters such as % predicted forced vital capacity (FVC), % predicted forced expiratory volume in 1 s (FEV1) and FEV1/FVC. However, decline in FEV1 was significantly correlated with AC. Multivariate logistic regression analysis showed that AC was a significant discriminating factor for decline in FEV1, independently of age, Brinkman index and change in body mass index from visit 1 to visit 2. At visit 2, there was a greater prevalence of decline in FEV1 among subjects with Mets (n=17) than among those without Mets. Although there were no differences in % predicted FVC, % predicted FEV1 or FEV1/FVC between subjects with or without Mets, the rate of decline in FEV1 was significantly greater in subjects with Mets than in those without.
Conclusions:This retrospective analysis suggested that measuring AC may be useful for discriminating male smokers who show a decline in FEV1.
decline in FEV1; abdominal circumference; smoker; health check.
Background: A study was undertaken to define the risk of death among a national cohort of US adults both with and without lung disease.
Methods: Participants in the first National Health and Nutrition Examination Survey (NHANES I) followed for up to 22 years were studied. Subjects were classified using a modification of the Global Initiative for Chronic Obstructive Lung Disease criteria for chronic obstructive pulmonary disease (COPD) into the following mutually exclusive categories using the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, and the presence of respiratory symptoms: severe COPD, moderate COPD, mild COPD, respiratory symptoms only, restrictive lung disease, and no lung disease. Proportional hazard models were developed that controlled for age, race, sex, education, smoking status, pack years of smoking, years since quitting smoking, and body mass index.
Results: A total of 1301 deaths occurred in the 5542 adults in the cohort. In the adjusted proportional hazards model the presence of severe or moderate COPD was associated with a higher risk of death (hazard ratios (HR) 2.7 and 1.6, 95% confidence intervals (CI) 2.1 to 3.5 and 1.4 to 2.0), as was restrictive lung disease (HR 1.7, 95% CI 1.4 to 2.0).
Conclusions: The presence of both obstructive and restrictive lung disease is a significant predictor of earlier death in long term follow up.
Classification of COPD into different GOLD stages is based on forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) but has shown to be of limited value. The aim of the study was to relate spirometry values to more advanced measures of lung function in COPD patients compared to healthy smokers. The lung function of 65 COPD patients and 34 healthy smokers was investigated using flow-volume spirometry, body plethysmography, single breath helium dilution with CO-diffusion, and impulse oscillometry. All lung function parameters, measured by body plethysmography, CO-diffusion, and impulse oscillometry, were increasingly affected through increasing GOLD stage but did not correlate with FEV1 within any GOLD stage. In contrast, they correlated fairly well with FVC%p, FEV1/FVC, and inspiratory capacity. Residual volume (RV) measured by body plethysmography increased through GOLD stages, while RV measured by helium dilution decreased. The difference between these RV provided valuable additional information and correlated with most other lung function parameters measured by body plethysmography and CO-diffusion. Airway resistance measured by body plethysmography and impulse oscillometry correlated within COPD stages. Different lung function parameters are of importance in COPD, and a thorough patient characterization is important to understand the disease.
Among older persons, we previously endorsed a two-step spirometric definition of chronic obstructive pulmonary disease (COPD) that requires a ratio of forced expiratory volume in 1-second to forced vital capacity (FEV1/FVC) below .70, and an FEV1 below the 5th or 10th standardized-residual percentile (“SR-tile strategy”).
To evaluate the clinical validity of an SR-tile strategy, compared to a current definition of COPD, as published by the Global Initiative for Obstructive Lung Disease (GOLD-COPD), in older persons.
We assessed national data from 2,480 persons aged 65-to-80 years. In separate analyses, we evaluated the association of an SR-tile strategy with mortality and respiratory symptoms, relative to GOLD-COPD. As per convention, GOLD-COPD was defined solely by an FEV1/FVC<.70, with severity staged according to FEV1 cut-points at 80 and 50 percent-predicted (%Pred).
Among 831 participants with GOLD-COPD, the risk of death was elevated only in 179 (21.5%) of those who also had an FEV1 <5thSR-tile; and the odds of having respiratory symptoms was elevated only in 310 (37.4%) of those who also had an FEV1 <10thSR-tile. In contrast, GOLD-COPD staged at an FEV1 50-79%Pred led to misclassification (overestimation) in terms of 209 (66.4%) and 77 (24.6%) participants, respectively, not having an increased risk of death or likelihood of respiratory symptoms.
Relative to an SR-tile strategy, the majority of older persons with GOLD-COPD had neither an increased risk of death nor an increased likelihood of respiratory symptoms. These results raise concerns about the clinical validity of GOLD guidelines in older persons.
COPD; spirometry; respiratory symptoms; mortality
A study was undertaken to determine if quantitative CT estimates of lung parenchymal overinflation and airway dimensions in smokers with a normal forced expiratory volume in 1 s (FEV1) can predict the rapid decline in FEV1 that leads to chronic obstructive pulmonary disease (COPD).
Study participants (n = 143; age 45–72 years; 54% male) were part of a lung cancer screening trial, had a smoking history of >30 pack years and a normal FEV1 and FEV1/forced vital capacity (FVC) at baseline (mean (SD) FEV1 99.4 (12.8)%, range 80.2–140.7%; mean (SD) FEV1/FVC 77.9 (4.4), range 70.0–88.0%). An inspiratory multislice CT scan was acquired for each subject at baseline. Custom software was used to measure airway lumen and wall dimensions; the percentage of the lung inflated beyond a predicted maximal lung inflation, the low attenuation lung area with an x ray attenuation lower than −950 HU and the size distribution of the overinflated lung areas and the low attenuation area were described using a cluster analysis. Multiple regression analysis was used to test the hypothesis that these CT measurements combined with other baseline characteristics might identify those who would develop an excessive annual decline in FEV1.
The mean (SD) annual change in FEV1 was −2.3 (4.7)% predicted (range −23.0% to +8.3%). Multiple regression analysis revealed that the annual change in FEV1%predicted was significantly associated with baseline percentage overinflated lung area measured on quantitative CT, FEV1%predicted, FEV1/FVC and gender.
Quantitative CT scan evidence of overinflation of the lung predicts a rapid annual decline in FEV1 in smokers with normal FEV1.
The Global Initiative on Obstructive Lung Disease stages for chronic obstructive pulmonary disease (COPD) uses a fixed ratio of the post‐bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) of 0.70 as a threshold. Since the FEV1/FVC ratio declines with age, using the fixed ratio to define COPD may “overdiagnose” COPD in older populations.
To determine morbidity and mortality among older adults whose FEV1/FVC is less than 0.70 but more than the lower limit of normal (LLN).
The severity of COPD was classified in 4965 participants aged ⩾65 years in the Cardiovascular Health Study using these two methods and the age‐adjusted proportion of the population who had died or had a COPD‐related hospitalisation in up to 11 years of follow‐up was determined.
1621 (32.6%) subjects died and 935 (18.8%) had at least one COPD‐related hospitalisation during the follow‐up period. Subjects (n = 1134) whose FEV1/FVC fell between the LLN and the fixed ratio had an increased adjusted risk of death (hazard ratio (HR) 1.3, 95% CI 1.1 to 1.5) and COPD‐related hospitalisation (HR 2.6, 95% CI 2.0 to 3.3) during follow‐up compared with asymptomatic individuals with normal lung function.
In this cohort, subjects classified as “normal” using the LLN but abnormal using the fixed ratio were more likely to die and to have a COPD‐related hospitalisation during follow‐up. This suggests that a fixed FEV1/FVC ratio of <0.70 may identify at‐risk patients, even among older adults.
BACKGROUND—It has been
suggested that oxidative stress is an important factor in the
pathogenesis of chronic obstructive pulmonary disease (COPD). We have
shown that an oxidant/antioxidant imbalance occurs in the distal air
spaces of smokers and in patients with COPD which is reflected
systemically in the plasma. A study was undertaken to determine whether
plasma antioxidant status correlated with lung function as assessed by
forced expiratory volume in one second (FEV1) and forced
vital capacity (FVC) in smokers and patients with COPD.
antioxidant capacity, assessed by the Trolox equivalent antioxidant
capacity (TEAC) as an index of overall systemic oxidative stress, and
protein thiol levels were measured in 95patients with stable COPD, in
82 healthy smokers, and in 37 healthy non-smokers.
plasma TEAC levels were significantly decreased in patients with COPD
(0.81 (0.03) mmol/l, p<0.001) and in healthy smokers (0.87 (0.04) mmol/l, p<0.001) compared with healthy non-smokers (1.31 (0.11) mmol/l). The mean differences in plasma antioxidant capacity
(mM) were (0.81, 95% confidence interval (CI) 0.22 to 1.48), (0.87, 95% CI 0.2 to 1.46), and (1.31, 95% CI 1.09 to 1.58) in patients with
COPD, healthy smokers, and healthy non-smokers, respectively. This
reduction was associated with a 29% (95% CI 18 to 38) and a 30%
(95% CI 19 to 40) decrease in plasma protein thiol levels in COPD
patients and smokers, respectively. Current smoking was not the main
contributor to the reduction in antioxidant capacity in patients with
COPD as those patients who were still smokers had similar TEAC levels
(mean (SE) 0.78 (0.05); n = 25) to those who had stopped smoking (0.84 (0.02); n = 70). No significant correlations were found between
spirometric data measured as FEV1 % predicted or
FEV1/FVC % predicted and the plasma levels of TEAC in
patients with COPD, healthy smokers, or healthy non-smokers. Similarly,
there was no significant correlation between FEV1 %predicted or FEV1/FVC % predicted and the levels of plasma
protein thiols in the three groups.
confirm decreased antioxidant capacity in smokers and patients with
COPD, indicating the presence of systemic oxidative stress. However, no
relationship was found between protein thiols or TEAC levels and
measurements of airflow limitation in either smokers or in patients
The Global initiative for chronic Obstructive Lung Disease (GOLD) defines COPD as a fixed post-bronchodilator ratio of forced expiratory volume in 1 second and forced vital capacity (FEV1/FVC) below 0.7. Age-dependent cut-off values below the lower fifth percentile (LLN) of this ratio derived from the general population have been proposed as an alternative. We wanted to assess the diagnostic accuracy and prognostic capability of the GOLD and LLN definition when compared to an expert-based diagnosis.
In a prospective cohort study, 405 patients aged ≥ 65 years with a general practitioner's diagnosis of COPD were recruited and followed up for 4.5 (median; quartiles 3.9; 5.1) years. Prevalence rates of COPD according to GOLD and three LLN definitions and diagnostic performance measurements were calculated. The reference standard was the diagnosis of COPD of an expert panel that used all available diagnostic information, including spirometry and bodyplethysmography.
Compared to the expert panel diagnosis, 'GOLD-COPD' misclassified 69 (28%) patients, and the three LLNs misclassified 114 (46%), 96 (39%), and 98 (40%) patients, respectively. The GOLD classification led to more false positives, the LLNs to more false negative diagnoses. The main predictors beyond the FEV1/FVC ratio for an expert diagnosis of COPD were the FEV1 % predicted, and the residual volume/total lung capacity ratio (RV/TLC). Adding FEV1 and RV/TLC to GOLD or LLN improved the diagnostic accuracy, resulting in a significant reduction of up to 50% of the number of misdiagnoses. The expert diagnosis of COPD better predicts exacerbations, hospitalizations and mortality than GOLD or LLN.
GOLD criteria over-diagnose COPD, while LLN definitions under-diagnose COPD in elderly patients as compared to an expert panel diagnosis. Incorporating FEV1 and RV/TLC into the GOLD-COPD or LLN-based definition brings both definitions closer to expert panel diagnosis of COPD, and to daily clinical practice.
COPD diagnosis; lower limit of normal; GOLD; validation
Recent reports indicate that over the next decade rates of chronic obstructive pulmonary disease (COPD) in women will exceed those in men in the western world, though in most jurisdictions, women continue to smoke less compared with men. Whether female adult smokers are biologically more susceptible to COPD is unknown. This study reviewed the available evidence to determine whether female adult smokers have a faster decline in forced expiratory volume in one second (FEV1) compared with male adult smokers and whether age modifies the relationship between cigarette smoke and lung function decline.
A systematic review and a meta-analysis was performed of population-based cohort studies that had a follow-up period of at least 3 years, measured FEV1 on at least two different time points, and presented FEV1 data stratified by gender and smoking status in adults.
Of the 646 potentially relevant articles, 11 studies met these criteria and were included in the analyses (N = 55 709 participants). There was heterogeneity in gender-related results across the studies. However, on average current smokers had a faster annual decline rate in FEV1% predicted compared with never and former smokers. Female current smokers had with increasing age a significantly faster annual decline in FEV1% predicted than male current smokers (linear regression analysis, R2 = 0.56; p = 0.008). Age did not materially affect the rate of decline in FEV1% predicted in male and female former and never smokers (p = 0.775 and p = 0.326, respectively).
As female smokers age, they appear to experience an accelerated decline in FEV1% predicted compared with male smokers. Future research powered specifically on gender-related changes in lung function is needed to confirm these early findings.
In patients with COPD, there is an evidence of platelet activation due to chronic hypoxia and systemic inflammation. Aim of the study was to evaluate Mean Platelet Volume (MPV) and Platelet Distribution Width (PDW), markers of platelet activation, in patients with Chronic Obstructive Pulmonary Disease (COPD), and to investigate possible associations with pulmonary function testing [Forced expiratory volume in 1 second (FEV1) and Forced vital capacity (FVC)].
Patients and methods
Current smokers with stable COPD (n=85) and smokers without airflow limitation (n=35) were included. To all of them pulmonary function testing was performed and count of white blood cells (WBC) platelets, as well as MPV and PDW were measured.
In smokers with COPD, MPV was significantly higher (mean value 10.563±1.531 vs. 9.956±1.046 fl, P<0.05) than in control group. WBC was also significantly higher in patients with COPD than in controls (9045.53±2664.34/μL vs. 7018.79±1989.74/μL, P<0.001). A significant correlation between MPV and WBC in COPD patients was revealed, especially in those at GOLD Stage III (r=0.475, P=0.012) and IV (r=0.367, P=0.033). WBC count was correlated with FEV1/FVC values (P=0.044). MPV did not correlate with any indices of COPD severity.
In patients with COPD, MPV and WBC levels are significantly correlated and are elevated in comparison to smokers with normal pulmonary function. WBC count was negatively correlated with FEV1/FVC values.
People with known risk factors for chronic obstructive pulmonary disease (COPD) are important targets for screening and early intervention. We sought to measure the prevalence of COPD among such individuals visiting a primary care practitioner for any reason. We also evaluated the accuracy of prior diagnosis or nondiagnosis of COPD and identified associated clinical characteristics.
We recruited patients from three primary care sites who were 40 years or older and had a smoking history of at least 20 pack-years. Participants were asked about respiratory symptoms and underwent postbronchodilator spirometry. COPD was defined as a ratio of forced expiratory volume in the first second of expiration to forced vital capacity (FEV1/FVC) of less than 0.7 and an FEV1 of less than 80% predicted.
Of the 1459 patients who met the study criteria, 1003 (68.7%) completed spirometry testing. Of these, 208 were found to have COPD, for a prevalence of 20.7% (95% confidence interval 18.3%–23.4%). Of the 205 participants with COPD who completed the interview about respiratory symptoms before spirometry, only 67 (32.7%) were aware of their diagnosis before the study. Compared with patients in whom COPD had been correctly diagnosed before the study, those in whom COPD had been over-diagnosed or undiagnosed were similar in terms of age, sex, current smoking status and number of visits to a primary care practitioner because of a respiratory problem.
Among adult patients visiting a primary care practitioner, as many as one in five with known risk factors met spirometric criteria for COPD. Underdiagnosis of COPD was frequent, which suggests a need for greater screening of at-risk individuals. Knowledge of the prevalence of COPD will help plan strategies for disease management.
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for chronic obstructive pulmonary disease (COPD) uses the post-bronchodilator spirometry for diagnosis and severity staging. We evaluated differences in the severity classification of COPD, based on pre- and post-bronchodilator spirometry.
Materials and Methods
From 2000 to 2004, 207 COPD patients who underwent spirometry before and after inhalation of 400 µg of fenoterol were analyzed. A responder to the bronchodilator test (BDT) was defined by the American Thoracic Society (ATS) as an increase in forced expiratory volume in one second (FEV1) or forced vital capacity ≥ 12% and ≥ 200 mL, and by the European Respiratory Society (ERS) as an increase in FEV1 ≥ 10% of the predicted value. COPD severity was classified according to the 2008 GOLD guidelines.
For the entire study population, the FEV1 increased by 11.8 ± 12.5% of baseline after BDT and 41.1% and 27.1% of subjects were classified as responders using the ATS and ERS criteria, respectively. Based on pre-BDT spirometry, 55, 85, 58, and 9 patients were classified as Stage I-IV COPD, respectively. Sixty-seven (32.4%) patients changed severity staging after BDT, including 20.0%, 28.2%, 44.8%, and 66.7% of pre-BDT patients Stages I through IV, respectively. More ATS or ERS BDT-responders had a change in severity staging than non-responders (52.9% vs. 18.9% and 62.5% vs. 21.2%, both p < 0.001).
Our data suggest that the severity staging of COPD using pre-BDT spirometry might lead to significant differences as compared to staging, based on post-BDT spirometry, as recommended by the current GOLD guidelines.
Bronchodilator test; chronic obstructive pulmonary disease; severity staging
There is limited information available regarding the association between lung function and bone mineral density among healthy elderly subjects. We addressed this issue in the Hertfordshire Cohort Study.
985 subjects (496 men and 489 women) aged 60-72 years were recruited from the above cohort. All subjects underwent bone density measurements using dual energy X-ray absorptiometry (DXA), and lung function tests using standardised spirometry. Chronic obstructive pulmonary disease (COPD) was defined as a Forced Expiratory Volume in 1 second (FEV1)/ Forced Vital Capacity (FVC) ratio < lower limit of normal (LLN), calculated using separate equations for men and women.
Measures of lung function (FEV1, FVC, FEV1/FVC) were not associated with bone mineral density at the lumbar spine, femoral neck and total hip in men or women; associations with bone mineral content and bone area were removed by adjustment for body size and lifestyle confounders. In this cohort, there were no associations observed between COPD and any measure of bone mass.
There was no association between lung function and bone mass in this community dwelling cohort after adjustment for body size and other confounders.
Bone disease; chronic bronchitis; epidemiology; osteoporosis; spirometry
To examine whether change in slow vital capacity (SVC) correlates to dyspnea improvement during emergency department (ED) treatment of chronic obstructive pulmonary disease (COPD) exacerbation.
We performed a prospective cohort study and enrolled consecutive patients during a 3-week period. ED patients ≥ 55 years old with COPD exacerbation were asked to perform bedside spirometry shortly after ED arrival and again at discharge. SVC was measured first, then forced expiratory volume in the first second (FEV1), peak expiratory flow (PEF), and forced vital capacity (FVC). Concurrent with spirometry, patients rated their dyspnea on a 10-cm visual analogue scale.
Thirty-six patients were enrolled. The median ED stay was 271 min (interquartile range 219–370 min). Seventy-one percent of the patients reported dyspnea improvement during their ED stay. Change in SVC was significantly higher among the patients whose dyspnea improved than among those whose did not (median increase of 0.15 L vs median decrease of 0.25 L, respectively, p < 0.01). By contrast, the change in spirometry values were similar for FEV1, PEF, and FVC (all p > 0.30). Spearman correlation supported these findings: SVC r = 0.45 (p = 0.02) versus nonsignificant correlation with FEV1 (r = 0.33), PEF (r = −0.22), and FVC (r = 0.35).
Increase in SVC significantly correlated with dyspnea improvement among ED patients with moderate-to-severe COPD exacerbation. Change in SVC merits consideration when evaluating therapeutic response during COPD exacerbation.
chronic obstructive pulmonary disease; COPD; dyspnea; emergency department; exacerbation; slow vital capacity; spirometry
Rationale: A significant proportion of smokers have lung function impairment characterized by a reduced FEV1 with a preserved FEV1/FVC ratio. These smokers are a poorly characterized group due to their systematic exclusion from chronic obstructive pulmonary disease (COPD) studies.
Objectives: To characterize the clinical, functional, and radiographic features of Global Initiative for Chronic Obstructive Lung Disease (GOLD)-Unclassified (FEV1/FVC ≥ 0.7 and FEV1 < 80% predicted) and lower limits of normal (LLN)-unclassified (FEV1/FVC ≥ LLN and FEV1 < LLN) subjects compared to smokers with normal lung function and subjects with COPD.
Methods: Data from the first 2,500 subjects enrolled in the COPDGene study were analyzed. All subjects had 10 or more pack-years of smoking and were between the ages of 45 and 80 years. Multivariate regression models were constructed to determine the clinical and radiological variables associated with GOLD-Unclassified (GOLD-U) and LLN-Unclassified status. Separate multivariate regressions were performed in the subgroups of subjects with complete radiologic measurement variables available.
Measurements and Main Results: GOLD-U smokers account for 9% of smokers in COPDGene and have increased body mass index (BMI), a disproportionately reduced total lung capacity, and a higher proportion of nonwhite subjects and subjects with diabetes. GOLD-U subjects exhibit increased airway wall thickness compared to smoking control subjects and decreased gas trapping and bronchodilator responsiveness compared to subjects with COPD. When LLN criteria were used to define the “unclassified” group, African American subjects were no longer overrepresented. Both GOLD-U and LLN-Unclassified subjects demonstrated a wide range of lung function impairment, BMI, and percentage of total lung emphysema.
Conclusions: Subjects with reduced FEV1 and a preserved FEV1/FVC ratio are a heterogeneous group with significant symptoms and functional limitation who likely have a variety of underlying etiologies beyond increased BMI.
Clinical trial registered with www.clinicaltrials.gov (NCT000608764).
lung diseases, classification; lung diseases, diagnosis; lung diseases, epidemiology
The aim of this study was to evaluate the effects of increasing doses of inhaled histamine on the forced expiratory volume in one second (FEV1), inspiratory lung function parameters (ILPs) and dyspnea in subjects with mild to moderate chronic obstructive pulmonary disease (COPD)
Thirty-nine (27 males and 12 females) stable COPD patients (GOLD stages I and II) inhaled a maximum of six sequential doses of histamine according to ERS standards until one of these provocative doses produced a 20% decrease in FEV1 (PD20). The effects on the FEV1, the forced inspiratory volume in one second (FIV1), inspiratory capacity (IC), forced inspiratory flow at 50% of the vital capacity (FIF50), peak inspiratory flow (PIF) and dyspnea score by a visual analogue scale (VAS) were measured and investigated after each dose step
After each dose of histamine, declines in all of the lung function parameters were detected; the largest decrease was observed in the FEV1. At the PD20 endpoint, more FEV1 responders than ILP responders were found. Among the ILPs, the FIV1 and IC best predicted which patients would reach the PD20 endpoint. No significant correlations were found between any of the lung function parameters and the VAS results
In COPD patients, the FEV1 and ILPs declined after each dose of inhaled histamine. FEV1 was more sensitive to histamine than the ILPs. Of the ILPs, FIV1 and IC were the best predictors of reaching the PD20 endpoint. No statistically significant correlations were found between the lung function parameters and the degree of dyspnea
Chronic obstructive pulmonary disease; Forced expiratory volume 1 second; Inspiratory lung functions parameters; Visual analogue scale
To determine the accuracy of the history and selected elements of the physical examination in the diagnosis of chronic obstructive pulmonary disease (COPD).
Independent blind comparison of the standard clinical examination (evaluating the accuracy of history, wheezing, and forced expiratory time [FET]) with spirometry. The gold standard for diagnosis of COPD was a forced expiratory volume at 1 second (FEV1) below the fifth percentile (adjusted for patient height and age).
Seven sites in 6 countries, including investigators from primary care and secondary care settings.
One hundred sixty-one consecutive patients with varying severity of disease (known COPD, suspected COPD, or no COPD) participated in the study.
One hundred sixty-one patients (mean age 65 years, 39% female, 41% with known COPD, 27% with suspected COPD, and 32% normal) were recruited. Mean (±SD) FEV1 and forced vital capacity were 1,720 (±830) mL and 2,520 (±970) mL. The likelihood ratios (LR) for the tested elements of the clinical examination (and their P values on χ2 testing) were: self-reported history of COPD, 5.6 (P < .001); FET greater than 9 seconds, 6.7 (P < 0.01); smoked longer than 40 pack years, 3.3 (P = .001); wheezing, 4.0 (P < .001); male gender, 1.6 (P < .001); and age over 65 years, 1.6 (P = .025). The accuracy of these elements was not appreciably different when reference standards other than FEV1 below the 5th percentile were applied. Only 3 elements of the clinical examination were significantly associated with the diagnosis of COPD on multivariate analysis: self-reported history of COPD (adjusted LR 4.4), wheezing (adjusted LR 2.9), and FET greater than 9 seconds (adjusted LR 4.6). Area under the receiver operating characteristic curve for the model incorporating these 3 factors was 0.86.
Less emphasis should be placed on the presence of isolated symptoms or signs in the diagnosis of COPD. While numerous elements of the clinical examination are associated with the diagnosis of COPD, only 3 are significant on multivariate analysis. Patients having all 3 of these findings have an LR of 33 (ruling in COPD); those with none have an LR of 0.18 (ruling out COPD).
chronic obstructive pulmonary disease; clinical examination; spirometry; diagnosis
Never smokers comprise a substantial proportion of patients with COPD. Their characteristics and possible risk factors in this population are not yet well defined.
We analyzed data from 14 countries that participated in the international, population-based Burden of Obstructive Lung Disease (BOLD) study. Participants were aged ≥ 40 years and completed postbronchodilator spirometry testing plus questionnaires about respiratory symptoms, health status, and exposure to COPD risk factors. A diagnosis of COPD was based on the postbronchodilator FEV1/FVC ratio, according to current GOLD (Global Initiative for Obstructive Lung Disease) guidelines. In addition to this, the lower limit of normal (LLN) was evaluated as an alternative threshold for the FEV1/FVC ratio.
Among 4,291 never smokers, 6.6% met criteria for mild (GOLD stage I) COPD, and 5.6% met criteria for moderate to very severe (GOLD stage II+) COPD. Although never smokers were less likely to have COPD and had less severe COPD than ever smokers, never smokers nonetheless comprised 23.3% (240/1,031) of those classified with GOLD stage II+ COPD. This proportion was similar, 20.5% (171/832), even when the LLN was used as a threshold for the FEV1/FVC ratio. Predictors of COPD in never smokers include age, education, occupational exposure, childhood respiratory diseases, and BMI alterations.
This multicenter international study confirms previous evidence that never smokers comprise a substantial proportion of individuals with COPD. Our data suggest that, in addition to increased age, a prior diagnosis of asthma and, among women, lower education levels are associated with an increased risk for COPD among never smokers.
The aim of our study is to determine whether chronic obstructive pulmonary disease (COPD) is an independent risk factor for ischemic heart disease and whether this association is related with a greater prevalence of classical cardiovascular risk factors. Ours is a case-control cross-sectional study design. Cases were hospital patients with ischemic heart disease in stable phase, compared with control hospital patients. All patients underwent post-bronchodilator (PBD) spirometry, a standardized questionnaire, and blood analysis. COPD was defined as per GOLD PBD forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.70. In our series of patient cases (n = 204) and controls (n = 100), there were 169 men in the case group (83%) and 84 in the control group (84%). Ages were 67 and 64 years, respectively (P < 0.05). There were no significant differences by weight, body mass index (BMI), packyears, leukocytes, or homocysteine. The abdominal perimeter was significantly greater in cases (mean 101 cm ± standard deviation [SD] 10 versus 96 cm ± 11; P < 0.000). Both groups also had significant differences by C-reactive protein (CRP), fibrinogen, and hemoglobin values. In univariate analysis, increased risks for cases to show with individual classical cardiovascular risk factors were seen, with odds ratio (OR) 1.86 and 95% confidence interval (CI) (1.04–3.33) for diabetes mellitus, dyslipidemia (OR 2.10, 95% CI: 1.29–3.42), arterial hypertension (OR 2.47, 95% CI: 1.51–4.05), and increased abdominal perimeter (OR 1.71, 95% CI: 1.06–2.78). Percent predicted PBD FEV1 was 97.6% ± 23% in the patient group and 104% ± 19% in the control group (P = 0.01), but the prevalence of COPD was 24.1% in cases and 21% in controls. Therefore, COPD was not associated with ischemic heart disease: at the crude level (OR 1.19, 95% CI: 0.67–2.13) or after adjustment (OR 1.14, 95% CI:0.57–2.29). In conclusion, COPD was not associated with ischemic heart disease. The greater prevalence of classical cardiovascular risk factors in COPD patients could explain the higher occurrence of ischemic heart disease in these patients.
chronic obstructive pulmonary disease; cardiovascular disease; systemic inflammation; comorbidity
It has been debated whether treatment should be started early in subjects with mild to moderate COPD. An impaired health status score was associated with a higher probability of being diagnosed with COPD as compared with undiagnosed COPD.
To investigate the health status in a healthy working population, to determine reference scores for healthy non-smoking subjects, and to investigate the relationship between their health status and airflow limitation.
A total of 1333 healthy industrial workers aged ≥40 years performed spirometry and completed the St. George’s Respiratory Questionnaire (SGRQ) and the COPD Assessment Test (CAT).
The prevalence of COPD defined by the fixed ratio of the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) was 10.9%, and the prevalence defined by the Lower Limit of Normal was 5.0%. All SGRQ and CAT scores were skewed to the milder end. In 512 non-smoking subjects with normal spirometry, the mean SGRQ score was 5.7, and the mean CAT score was 5.8. In 145 people with COPD defined by the fixed ratio, the mean SGRQ score was 7.9, with a zero score in 6.9% of the subjects. Using the CAT, the mean score was 7.3, with 7.6% of the scores being zero. The scores in patients identified using the Lower Limit of Normal approach were: SGRQ 8.4 (13.4% had a score of zero) and CAT 7.4 (13.4% had a score of zero). Although the 95th percentiles of the Total, Symptoms, Activity, and Impact scores of the SGRQ and CAT sores were 13.8, 34.0, 23.4, 7.2 and 13.6 in the 512 healthy non-smoking subjects, respectively, they were also distributed under their upper limits in over 80% of the COPD subjects.
The COPD-specific health status scores in a working population were good, even in those with spirometrically diagnosed COPD. All scores were widely distributed in both healthy non-smoking subjects and in subjects with COPD, and the score distribution overlapped remarkably between these two groups. This suggests that symptom-based methods are not suitable screening tools in a healthy general population.
Chronic obstructive pulmonary disease; St. George’s Respiratory Questionnaire; Symptoms and COPD; Smoking and health; Health related quality of life
Background: The Global Initiative for Obstructive Lung Disease (GOLD) has defined chronic obstructive pulmonary disease (COPD) as a post-bronchodilator ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) of <0.7. In the first general population based study to apply post-bronchodilator values, the prevalence and predictors of GOLD defined COPD were assessed and the implications of ß2 agonist reversibility testing examined.
Methods: Based on a random population sample, 2235 subjects (77%) aged 26–82 years performed spirometric tests before and 15 minutes after inhaling 0.3 mg salbutamol.
Results: The prevalence of GOLD defined COPD was 7.0% (95% confidence interval (CI) 5.9 to 8.0). This estimate was 27% lower than COPD defined without bronchodilatation. One percent of the population had severe or very severe COPD. Compared with women, men had 3.1 (95% CI 2.1 to 4.8) times higher odds for COPD. Subjects with a smoking history of more than 20 pack years had an odds ratio (OR) of 6.2 (95% CI 3.4 to 11.0) for COPD relative to never-smokers, while subjects older than 75 years had an OR of 18.0 (95% CI 9.2 to 35.0) relative to those below 45 years. Subjects with primary education only had an OR of 2.8 (95% CI 1.4 to 5.3) compared with those with university education. Subjects with body mass index (BMI) <20 kg/m2 were more likely than subjects with BMI 25–29.9 kg/m2 to have COPD (OR 2.4, 95% CI 1.1 to 5.3). The adjusted proportion of COPD attributable to smoking was 68%.
Conclusions: These results indicate that community programmes on prevention of COPD should focus on anti-smoking, nutritional aspects, and socioeconomic conditions. The effect of ß2 reversibility testing on prevalence estimates of COPD was substantial.