Prevalence of COPD in India: a systematic review.

BACKGROUND: The increasing burden of chronic diseases is a particular risk to countries with developing health systems. Chronic obstructive pulmonary disease (COPD) is contributing to the burden of chronic diseases. Understanding the current prevalence of COPD in India is important for the production of sustainable management strategies. AIMS: To provide a systematic review of studies assessing the prevalence of COPD in India. METHODS: Database searches, journal hand searches, and scanning of reference lists were used to identify studies. Studies of general adult populations resident in India were included. Data extraction and quality assessment were carried out using pre-tested proformas. Owing to the heterogeneity of reviewed studies, meta-analysis was not appropriate. Thus, narrative methods were used. RESULTS: We did not identify any studies from which we could draw a rigorous estimate of the prevalence of COPD by standard definition. Reliable standard estimates of chronic bronchitis were only available for rural populations. We identified four studies that gave estimated prevalences between 6.5% and 7.7%, and others suggestive that prevalences in some environmentally atypical regions may lie outside this range. Sex and smoking status were relatively important predictors of COPD prevalence. Residential environs, age, and domestic smoke exposure are also important, but investigation of their effect was limited by study heterogeneity. CONCLUSIONS: Although limited by the number and heterogeneity of studies and their unsuitability for meta-analysis, we found the most rigorous existing estimates of the general prevalence of chronic bronchitis in rural areas to lie between 6.5% and 7.7%. These figures are unlikely to apply to all Indian subpopulations, so the general prevalence of chronic bronchitis in India remains unknown. Accurate estimates of the prevalence of chronic bronchitis/COPD from across the country are required to supplement existing data if optimal management strategies are to be devised.