Association between passive smoking and hypertension in Chinese non-smoking elderly women

Although active smoking is linked with hypertension, the effect of environmental tobacco smoke exposure on hypertension has rarely been studied, and the scant epidemiological data available have yielded uncertain findings. Therefore, we conducted a cross-sectional study in a representative urban area of Beijing, China. A two-stage stratified clustering sampling method was performed, and 1078 female participants aged >= 60 years were included in the analysis. Among the participants without antihypertensive treatment, > 2 hours of daily passive cigarette smoking was significantly associated with higher systolic (by 4.24) and diastolic blood pressure (by 2.09) after multiple adjustments. The prevalence of hypertension was significantly higher in passive smokers (71.9%) than in non-passive smokers (66.1%). After adjusting for potential confounders, a positive association was observed between passive smoking and the risk of hypertension, and the adjusted odds ratio (OR; 95% confidence interval (CI)) was 1.38 (1.03, 1.85). Inversely, the control rate of hypertension was significantly lower in passive smokers (26.3%) than in non-passive smokers (35.7%) among the hypertensive patients; the adjusted OR (95% CI) was 0.62 (0.44, 0.87). Furthermore, a dose-response association was observed between the amount and frequency of passive cigarette smoking and the control rate of hypertension. We demonstrated that passive smoking was significantly associated with the increased prevalence and lower control rate of hypertension in a community-based elderly population in Beijing, China. Additional randomized controlled trials and large prospective studies are still required to determine the relationship between passive smoking and hypertension among the Chinese elderly.