Prevalence and risk factors for self-reported asthma in an adult Indian population: a cross-sectional survey.

BACKGROUND AND METHODS: We estimated the prevalence of self-reported asthma in adult Indians and examined several risk factors influencing disease prevalence. Analysis is based on 99,574 women and 56,742 men aged 20-49 years included in India's third National Family Health Survey, 2005-2006. Multiple logistic regression analysis was used to estimate the prevalence odds ratios for asthma, adjusting for various risk factors. RESULTS: The prevalence of self-reported asthma was 1.8% (95%CI 1.6-2.0) among men and 1.9% (95%CI 1.8-2.0) among women, with higher rates in rural than in urban areas and marked geographic differences. After adjustment for known asthma risk factors, women were 1.2 times more likely to have asthma than men. Daily/weekly consumption of milk/milk products, green leafy vegetables and fruits were associated with a lower asthma risk, whereas consumption of chicken/meat, a lower body mass index (BMI; <16 kg/m(2), OR 2.08, 95%CI 1.73-2.50) as well as a higher BMI (>30 kg/m(2), OR 1.67, 95%CI 1.36-2.06), current tobacco smoking (OR 1.30, 95%CI 1.12-1.50) and ever use of alcohol (OR 1.21, 95%CI 1.05-1.39) were associated with an increased asthma risk. CONCLUSIONS: There are wide regional variations in the prevalence of asthma in India. With the exception of the findings for BMI, however, most of the associations of asthma with the risk factors are relatively weak and account for only a small proportion of cases.