Purpose: The aim of this study is to determine the relationship between SHS exposure and hypertension in self-reported and cotinine-verified never-smokers.
Methods: A total of 131,739 self-reported and cotinine-verified never-smokers (42,687 men; age 35.0±7.1 years) who participated in Kangbuk Samsung Health Study (KSHS) and Kangbuk Samsung Cohort study (KSCS) between 2011 and 2016 were included. Cotinine-verified never-smokers was defined as individuals having urinary cotinine <50 ng/mL. SHS exposure was defined as having experienced passive smoking indoors at home or the workplace.
Results: The prevalence of SHS exposure and hypertension was 22.9% and 5.9%, respectively. The prevalence of hypertension in group with SHS exposure was higher than that in group without SHS exposure (7.2% versus 5.5%, p<0.001). The multivariate regression model revealed that SHS exposure was associated with hypertension (odds ratio(OR)[95% confidence interval(CI)], 1.13[1.06, 1.21]). SHS exposure with = 1 hours/day, = 3 times/week, and = 10 years increased 13-17% for hypertension compared with no SHS exposure (1.14[1.00, 1.29], 1.13[1.03, 1.25], and 1.17[1.07, 1.28], respectively). Furthermore, SHS exposure was significantly associated with systolic blood pressure(SBP) and diastolic blood pressure(DBP) (regression coefficient[95% CI], 0.15[0.01, 0.28] for SBP and 0.18[0.07, 0.29] for DBP, all p<0.001). There was no significant gender interaction for the relationships between SHS exposure and hypertension.
Conclusion: This study showed that SHS exposure was significantly associated with hypertension in self-reported and cotinine-verified never-smokers, suggesting that necessity of health program and stricter smoking regulation to reduce the risk of hypertension.