Prevalence of Chronic Obstructive Pulmonary Disease and its Associated Factors in Nepal: Findings from a Community-based Household Survey

Background: Despite chronic obstructive pulmonary disease (COPD) being the commonest non-communicable disease in Nepal, there is limited research evidence estimating the spirometry-based burden of COPD. This study aims to estimate the prevalence of COPD and its correlates through a community-based survey in Pokhara Metropolitan City, a semiurban area of Western Nepal. Methods: A cross-sectional household survey was conducted among 1459 adults >= 40 years. COPD was defined according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria as a post-bronchodilator ratio of forced expiratory volume in 1st second (FEV1) to forced vital capacity (FVC) <0.70 with the presence of symptoms. COPD was also defined by the lower limit of normal (LLN) threshold - FEV1/FVC < LLN cut-off values with the presence of symptoms. Study participants were interviewed about sociodemographic and behavioural characteristics and respiratory symptoms. Descriptive statistics and logistic regression analysis were applied. Results: Spirometry reports were acceptable in 1438 participants. The mean age of the participants was 55 (+/- 10) years, and, 54% were female. The prevalence of GOLD-defined COPD was 8.5% (95% CI: 7.1-10.0) and based on the LLN threshold of 5.4% (95% CI: 4.2-6.6). The multivariate logistic regression showed that increasing age, low body mass index, illiterate, current or former smoker, and biomass fuel smoke increased the odds of COPD in both the definitions. Conclusion: COPD is highly prevalent at community level and often underdiagnosed. Strategies aiming at early diagnosis and treatment of COPD, especially for the elderly, illiterate, and reducing exposure to smoking and biomass fuel smoke and childhood lung infection could be effective.