Determinants of health-related quality of life among residents with and without COPD in a historically industrialised area.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is associated with substantial morbidity, including impaired health-related quality of life (HRQoL). Despite the prominent role of occupational factors in the aetiology of COPD, the relationship between these exposures and HRQoL has not been well elucidated. METHODS: A subpopulation from an epidemiological study, designed to assess the workplace contribution to COPD, was administered the EQ5D HRQoL tool. Demographics, an index of economic deprivation, health endpoints including the presence of COPD and lung function were also recorded. Workplace exposures were categorised using both self-reported exposures and also by the use of an established job exposure matrix (JEM). RESULTS: A total of 623 individuals participated (mean age 67.1 years). One hundred and forty-eight (24%) reported having received a physician diagnosis of COPD, 355 (57%) were male, and 386 (62%) were ever smokers. As anticipated, the presence of COPD was associated with a poorer HRQoL. Additionally, however, HRQoL was significantly lower in the presence of both self-reported vapours, gases, dusts and fumes exposure and JEM-based exposure irrespective of the presence of COPD. Regression analysis, adjusting for a variety of covariates including the presence of COPD, confirmed a persisting higher likelihood of occupational exposure categorised by JEM being associated with poorer HRQoL scores (ß estimate: -0.069; p < 0.05). CONCLUSIONS: Our findings suggest that work may have an important link to HRQoL and that this effect can persist even among those who have retired. In those with COPD, HRQoL is worse than among those without this condition, but the work-associated decrement appears to be similar across both groups.

Chronic obstructive pulmonary disease among residents of an historically industrialised area.

OBJECTIVE: To assess the contribution of workplace exposures to chronic obstructive pulmonary disease (COPD) risk in a community with a heavy burden of past industrial employment. METHODS: A random population sample of Sheffield, U.K. residents aged over 55 years (n=4000), enriched with a hospital-based supplemental sample (n=209), was approached for study. A comprehensive self-completed questionnaire elicited physician-made diagnoses, current symptoms, and past workplace exposures. The latter were defined in three ways: self-reported exposure to vapours, gases, dusts and fumes (VGDF); response to a specific exposure checklist; and through a job exposure matrix (JEM) assigning exposure risk likelihood based on job history independent of respondent-reported exposure. A subset of the study group underwent lung function testing. Population attributable risk fractions (PAR%), adjusted for age, sex and smoking, were calculated for association between workplace exposure and COPD. RESULTS: 2001 (50%) questionnaires were returned from the general population sample and 60 (29%) by the hospital supplement. Among 1754 with complete occupational data, any past occupational exposure to VGDF carried an adjusted excess risk for report of a physician's diagnosis of COPD, emphysema, or chronic bronchitis (ORs 3.9; 95% CI 2.7 to 5.8), with a corresponding PAR% value of 58.7% (95% CI 45.6% to 68.7%). The PAR% estimate based on JEM exposure was 31%. From within the subgroup of 571 that underwent lung function testing, VGDF exposure was associated with a PAR% of 20.0% (95% CI -7.2 to 40.3%) for Global initiative for chronic obstructive lung disease (GOLD) 1 (or greater) level of COPD. CONCLUSION: This heavy industrial community-based population study has confirmed significant associations between reported COPD and both generic VGDF and JEM-defined exposures. This study supports the predominantly international evidence-based notion that workplace conditions are important when considering the current and future respiratory health of the workforce.

Sensitization to wheat flour and enzymes and associated respiratory symptoms in British bakers.

RATIONALE: Current literature suggests that flour exposed workers continue to be at risk of allergic sensitization to flour dust and respiratory ill health. OBJECTIVES: A cross-sectional study of 225 workers currently potentially exposed to flour dust in British bakeries was performed to identify predictors of sensitization to wheat flour and enzymes. RESULTS: Work-related nasal irritation was the most commonly reported symptom (28.9%) followed by eye irritation (13.3%) and work-related cough or chest tightness (both 10.2%). Work-related chest tightness was significantly associated (OR 7.9, 1.3-46.0) with co-sensitization to wheat flour and any added enzyme. Working at a bakery with inadequate control measures was not a risk factor for reporting work-related respiratory symptoms (OR 1.3, 0.4-3.7). Fifty-one workers were atopic and 23 (14%) were sensitized to workplace allergens. Atopy was the strongest predictive factor (OR 18.4, 5.3-64.3) determining sensitization. Current versus never smoking (OR 4.7, 1.1-20.8) was a significant risk factor for sensitization to wheat flour or enzymes in atopic workers only, corrected for current level and duration of exposure. This effect was not seen in non-atopic workers (OR 1.9, 0.2-17.9). Evidence of sensitization to less commonly encountered allergens was also seen to Aspergillus niger derived cellulase, hemicellulase and xylanase mix, in addition to glucose oxidase and amyloglucosidase mix. CONCLUSIONS: The combination of health surveillance and exposure control in this population has been insufficient to prevent clinically significant workplace sensitization. Smoking may pose an additional risk factor for sensitization in atopic workers. Am. J. Ind. Med. 52:133-140, 2009.

Is inspiratory muscle training (IMT) an acceptable treatment option for people with chronic obstructive pulmonary disease (COPD) who have declined pulmonary rehabilitation (PR) and can IMT enhance PR uptake? A single-group prepost feasibility study in a home-based setting.

OBJECTIVES: This feasibility study aimed to assess the acceptability of inspiratory muscle training (IMT) in people with chronic obstructive pulmonary disease (COPD) who declined pulmonary rehabilitation (PR) as a potential treatment option or precursor to PR. Objectives were to assess attitudes to IMT, PR and alternatives to PR; factors influencing adherence with IMT and acceptability of outcome measures, research tools and study protocol. DESIGN: A pragmatic, mixed methods, prepost feasibility study was conducted. Recruitment took place over a 4-month period. Participants were followed up for a period of 6 months. SETTINGS: IMT sessions and assessments were conducted in the domiciliary setting. PARTICIPANTS: Inclusion criteria: people over the age of 35, stable COPD, Medical Research Council Dyspnoea scale of 3 or above, declined PR. EXCLUSION CRITERIA: history of spontaneous pneumothorax, incomplete recovery from a traumatic pneumothorax, asthma, known recently perforated eardrum, unstable angina, ventricular dysrhythmias, cerebrovascular event or myocardial infarction within the last 2 months. Participants were selected from a purposive sample. Of the 22 potential participants screened, 11 were recruited and interviewed. Ten participants commenced IMT. Seven participants completed the follow-up assessment. INTERVENTION: Eight weeks of IMT twice a day, 5 days a week with visits once weekly by a physiotherapist. Unsupervised IMT twice a day three times a week until follow-up at 6 months. OUTCOMES: Acceptability of IMT and the study process was explored via semi-structured interviews. Adherence with IMT was assessed by the Powerbreathe K3 device and participant diaries. Uptake of PR was identified. RESULTS: IMT was found to be acceptable. Adherence was explored. Four people went on to participate in PR. CONCLUSIONS: Feasibility was established. A randomised controlled trial is warranted to establish efficacy and cost-effectiveness of IMT in those who decline PR and IMT as an intervention to promote uptake of PR. TRIAL REGISTRATION NUMBER: NCT01956565; Post-results.

The incremental shuttle walk test predicts mortality in non-group 1 pulmonary hypertension: results from the ASPIRE Registry.

Pulmonary hypertension (PH) is classified into five groups based on disease etiology but there is only limited information on the prognostic value of exercise testing in non-group 1 PH. In group 1 PH, the incremental shuttle walking test (ISWT) distance has been shown to correlate with pulmonary hemodynamics and predict survival without a ceiling effect. This study assessed the ISWT in non-group 1 PH. Data were retrieved from the ASPIRE Registry (Assessing the Spectrum of Pulmonary hypertension Identified at a REferral centre) for consecutive patients diagnosed with PH. Patients were required to have been systematically assessed as group 2-5 PH and to have a baseline ISWT within three months of cardiac catheterization. Patients were stratified according to incremental shuttle walk test distance (ISWD) and ISWT distance percent predicted (ISWD%pred). A total of 479 patients with non-group 1 PH were identified. ISWD and ISWD%pred correlated significantly with symptoms and hemodynamic severity. ISWD and ISWD%pred predicted survival with no ceiling effect. The test was prognostic in groups 2, 3, and 4. ISWD and ISWD%pred and change in ISWD and ISWD%pred at one year were all significant predictors of outcome. In patients with non-group 1 PH the ISWT is a simple non-invasive test that is easy to perform, is predictive of survival at baseline and follow-up, reflects change, and can be used in the assessment of PH of any etiology.

Incremental shuttle walk test distance and autonomic dysfunction predict survival in pulmonary arterial hypertension.

BACKGROUND: To ensure effective monitoring of pulmonary arterial hypertension (PAH), a simple, reliable assessment of exercise capacity applicable over a range of disease severity is needed. The aim of this study was to assess the ability of the incremental shuttle walk test (ISWT) to correlate with disease severity, measure sensitivity to change, and predict survival in PAH. METHODS: We enrolled 418 treatment-naïve patients with PAH with baseline ISWT within 3 months of cardiac catheterization. Clinical validity and prognostic value of ISWT distance were assessed at baseline and 1 year. RESULTS: ISWT distance was found to correlate at baseline with World Health Organization functional class, Borg score, and hemodynamics without a ceiling effect (all p < 0.001). Walking distance at baseline and after treatment predicted survival; the area under the receiver operating characteristic curve for ability of ISWT distance to predict mortality was 0.655 (95% confidence interval 0.553-0.757; p = 0.004) at baseline and 0.737 (95% confidence interval 0.643-0.827; p < 0.001) at 1 year after initiation of treatment. Change in ISWT distance also predicted survival (p = 0.04). Heart rate (HR) and systolic blood pressure (SBP) parameters reflecting autonomic response to exercise (highest HR, change in HR, HR recovery at 1 minute >18 beats/min, highest SBP, change in SBP, and 3-minute SBP ratio) were significant predictors of survival (all p < 0.05). CONCLUSIONS: In patients with PAH, the ISWT is simple to perform, allows assessment of maximal exercise capacity, is sensitive to treatment effect, predicts outcome, and has no ceiling effect. Also, measures of autonomic function made post-exercise predict survival in PAH.

Emphysematous changes and normal variation in smokers and COPD patients using diffusion 3He MRI.

INTRODUCTION: This study aims to quantify global and regional changes of diffusive motion of 3He gas within the lung, as determined by hyperpolarized 3He MR apparent diffusion coefficient (ADC) measurement, in non-smokers, smokers and chronic obstructive pulmonary disease (COPD) patients. METHODS: Age-matched groups of six healthy non-smokers, five healthy smokers and five patients with COPD. The experiments were performed with approval from the local Research Ethics Committee. Diffusion imaging was performed following hyperpolarized 3He gas inhalation, producing ADC maps. Mean and standard deviation of the ADCs were used to compare the subject groups and assess regional variations within individuals. RESULTS: The intra-individual standard deviation of ADC in the healthy smokers was significantly larger than that of the non-smoking group (P < 0.02). Compared to the non-smoking group, COPD patients had significantly higher mean and standard deviation of ADC (P < 0.01). The mean ADC in the anterior half of the chest was systematically higher than in the posterior half in the healthy non-smoking subject group. DISCUSSION: This study suggests that there are regional trends in the ADC values of healthy volunteers that may have implications for the clinical interpretation of ADC values. Less homogeneous ADC values have been detected in asymptomatic smokers, indicative of damage to the distal air spaces.