Prevalence and Determinants of Chronic Obstructive Pulmonary Disease (COPD) in Bangladesh

Rationale: There is a paucity of population-based data on COPD prevalence and its determinants in Bangladesh.

Objective: To measure COPD prevalence and socioeconomic and lifestyle determinants among ≥40 years Bangladeshi adults.

Methods: In a cross-sectional study, we measured lung function of 3744 randomly selected adults ≥40 years from rural and urban areas in Bangladesh, using a handheld spirometer. COPD was defined according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria as post-bronchodilator ratio of Forced Expiratory Volume in 1^st second (FEV₁) to Forced Vital Capacity (FVC) <?0.7. In addition, COPD was also assessed by the lower limit of normal (LLN) threshold defined as lower fifth percentile for the predicted FEV₁/FVC.

Results: The prevalence of COPD was 13.5% by GOLD criteria and 10.3% by LLN criteria. Prevalence of COPD was higher among rural than urban residents and in males than females. More than half of the COPD cases were stage II COPD by both criteria. Milder cases (Stages I and II) were over estimated by the GOLD fixed criteria, but more severe cases (Stages III and IV) were similarly classified. In multiple logistic regression analysis, older age, male sex, illiteracy, underweight, history of smoking (both current and former), history of asthma and solid fuel use were significant predictors of COPD.

Conclusion: COPD is a highly prevalent and grossly underdiagnosed public health problem in Bangladeshi adults aged 40 years or older. Illiteracy, smoking and biomass fuel burning are modifiable determinants of COPD.