Population attributable risk estimates for risk factors associated with hypertension in an Indian population

BACKGROUND: Little evidence exists regarding the magnitude of contribution of risk factors associated with hypertension in India. Determination of potentially modifiable risk factors is necessary to focus prevention strategies. DESIGN: Age-matched case-control study. METHODS: A total of 350 hypertensive cases and 350 controls of both sexes in the age group 20-65 years. Hypertension was defined according to JNC VII criteria. Adjusted odds ratio (OR) and population attributable risk percentage (PAR %) for hypertension were calculated. RESULTS: In multivariate analysis, tobacco users (either tobacco chewing/smoking or both) (adjusted OR 5.1, 95% CI 3.6-7.3), tobacco chewing (adjusted OR 3.2, 95% CI 2.2-4.6), smoking (adjusted OR 2.9, 95% CI 1.9-4.4), and alcohol consumption (adjusted OR 1.5, 95% CI 1.1-2.2) was the strongest determinants of hypertension. A dose-response relation was found between the number of cigarettes smoked per day (χ2 for trend = 26.07; p < 0.0001) and the amount of alcohol consumption per day (χ2 for trend = 24.26; p < 0.0001) and the risk of hypertension. PARs were 70.3% (95% CI 63.0-77.5) for tobacco use, 45.3% (95% CI 37.1-53.4) for tobacco chewing, 31.5% (95% CI 21.3-40.9) for smoking, and 33.6% (95% CI 22.9-44.4) for alcohol consumption. CONCLUSION: Our results indicate that incident hypertension cases are largely attributable to the habit of tobacco use and alcohol consumption. Therefore, changing these selected lifestyle factors needs to be prioritized as a major strategy for reducing incidence of hypertension in our population.