ABSTRACT
BACKGROUND AND OBJECTIVE: An estimated 25-40% of patients with chronic obstructive pulmonary disease (COPD) have never smoked. We investigated the prevalence and patient characteristics of COPD in non-smokers from Vietnam and Indonesia. METHODS: This population-based cross-sectional survey of participants from urban and rural Vietnam and Indonesia used a stratified multistage cluster sampling design, with sample and population weights applied to ensure representativeness. Participants were female or male (recruited in the ratio 2:1) non-smokers, 40 years or older and able to perform a spirometry test. Spirometry was performed at a single study visit. Other clinical information was collected via standardized questionnaires. RESULTS: The 1506 evaluable participants were approximately equally distributed between Vietnam and Indonesia, and rural and urban areas. Overall prevalence of COPD was found to be 6.9% (95% confidence interval (CI): 5.7-8.3), with almost three times higher prevalence in men than women (12.9% (95% CI: 9.1-18.0) vs 4.4% (95% CI: 3.0-6.5)). We found higher rates of COPD in Vietnam than Indonesia (8.1% (95% CI: 5.8-11.3) vs 6.3% (95% CI: 4.8-8.3)), with a particularly high prevalence in urban Vietnam (11.1% (95% CI: 8.1-15.1)). Very few participants (6%) diagnosed to have COPD during the study had been previously diagnosed with COPD. Respiratory symptoms and lower health-related quality of life were more common in participants with COPD. CONCLUSIONS: The prevalence of COPD in non-smoking individuals from rural and urban Vietnam and Indonesia was 6.9%, of which a significant proportion (94%) were previously undiagnosed.