Prevalence and characteristics of COPD among pneumoconiosis patients at an occupational disease prevention institute: a cross-sectional study

Abstract

BackgroundPneumoconiosis may play an important role in the development of chronic obstructive pulmonary disease (COPD), and the complication of COPD may impose a heavy burden of illness.MethodsThe study was conducted in Hunan Province in China from December 1, 2015, to December 1, 2016. Consecutive underground male pneumoconiosis patients employed for at least 1 year were recruited from the Hunan Occupational Disease Prevention Institute. Patient information, respiratory symptoms and clinical data were collected using a structured questionnaire. The diagnosis of COPD were assessed using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. Logistic regression analyses were conducted to examine the clinical and demographic risk factors of COPD among pneumoconiosis patients.ResultsThe prevalence of COPD in our sample of pneumoconiosis patients was 18.65% (119/638). In pneumoconiosis patients with and without smoking history, the prevalence of COPD was 19.32 and 16.77%. Compared with non-COPD patients, those with COPD are older in age, have longer exposure time, have lower body mass index (BMI), have a higher smoking index and have worse pulmonary function (all p < 0.05). For the five respiratory symptoms (cough, sputum, wheeze, dyspnea, and chest tightness), only the presence of wheeze and the severity scores for wheeze or dyspnea showed significant differences between the COPD and non-COPD groups (p < 0.01). Multivariate logistic regression analysis revealed that advanced pneumoconiosis category, older age and the presence of wheeze symptoms were significant risk factors for the development of COPD among pneumoconiosis patients.ConclusionPneumoconiosis patients are at a high risk of COPD, and pneumoconiosis patients with COPD may suffer more severe respiratory symptoms, such as wheeze and dyspnea, than patients without COPD. Advanced pneumoconiosis category, older age and the presence of wheeze symptoms are associated with an increased risk of COPD in pneumoconiosis. We proposed that a routine assessment of lung function is necessary for timely and adequate clinical management.

Prevalence of spirometry-defined airflow obstruction in never-smoking working US coal miners by pneumoconiosis status

“…Never-smoking working miners with CWP, identified by a chest radiograph as part of a voluntary surveillance programme, had a significantly higher prevalence of ATS/ERS airflow obstruction (16.4%) and moderate/severe airflow obstruction (3.5%) compared with those without CWP (7.5% and 1.0%, respectively), and airflow obstruction was more common in miners with PMF compared with those with simple CWP. A study of non-smoking Chinese underground miners with pneumoconiosis, identified in a clinical setting, reported the prevalence of Global Initiative for Chronic Obstructive Lung Disease (GOLD)-defined chronic obstructive pulmonary disease among these miners was 18.7% 9. In our study, airflow obstruction prevalence was highest in never-smoking miners with PMF (32.3%), indicating severe cases of pneumoconiosis can present with an obstructive pattern regardless of smoking status.…”

Association of occupational dust exposure with combined chronic obstructive pulmonary disease and pneumoconiosis: a cross-sectional study in China

“…The present study also found that over half (57.0%) of the patients were smokers and that the prevalence of COPD did not differ between smokers and non-smokers-these findings are in line with the data previously reported. 21 While these earlier studies are not directly comparable, the data indicate that combined COPD and pneumoconiosis occurs often in patients with certain types of pneumoconiosis.…”

“…A cross-sectional study of patients with silicosis or coal workers' pneumoconiosis from South China reported a COPD prevalence of 18.65% (119/638), which is lower than our finding. 21 One reason may be that our study had a higher percentage of smokers. It is also possible that the differences in COPD prevalence are a result of other differences in study participants and working conditions.…”

“…However, in previous research, no significant correlation was found between smoking and COPD in patients with pneumoconiosis. 21 A possible explanation of the inconsistency is the lack of stratification by smoking pack-years in the earlier work. Previous studies of COPD have examined occupational risk factors in addition to smoking.…”

“…To identify the risk factors for combined diseases, with 95% confidence and 80% power, 5 to 10 observations per previously demonstrated risk factors for COPD in pneumoconiosis patients were needed. 21 Based on the previous publication by Peng et al, 21 the prevalence of COPD among pneumoconiosis was 18.65%, the calculated sample size was 214 to 428. Furthermore, this study demonstrated risk factors for COPD in never-smokers subgroup.…”