Relationship between cigarette smoking and blood pressure in adults in Nepal: A population-based cross-sectional study

Smoking and hypertension are two major risk factors for cardiovascular disease, the leading cause of death in Nepal. The relationship between cigarette smoking and blood pressure (BP) in Nepal is unclear. This study analysed the data from the 2016 Nepal Demographic and Health Survey to explore the differences in systolic BP (SBP) and diastolic BP (DBP) between current daily cigarette smokers and non-smokers in Nepali adults aged 18 to 49 years. A total of 5518 women and 3420 men with valid BP measurements were included. Age, body mass index, wealth quintile (socio-economic status) and agricultural occupation (proxy for physical activity) were included as potential confounders in multivariable linear regression analysis. Women smokers were found to have significantly lower SBP (mean difference 2.8 mm, 95% CI 0.7–4.8 mm) and DBP (mean difference 2.2 mm, 95% CI 0.9–3.6 mm) than non-smokers after adjustment. There were no significant differences in BP between smokers and non-smokers in males, either before or after adjustment. The lower BP in female cigarette smokers in Nepal may be explained by the physiological effect of daily cigarette smoking per se in women, or unmeasured confounders associated with a traditional lifestyle that may lower BP (for example, diet and physical activity). In this nationally representative survey, daily cigarette smoking was not associated with increased BP in males or females in Nepal.