Association between Baseline SBP/DBP and All-Cause Mortality in Residents of Shanxi, China: A Population-based Cohort Study from 2002 to 2015

Objective To investigate the association between blood pressure and all-cause mortality in Shanxi, China. Methods The '2002 China Nutrition and Health Survey' baseline data in Shanxi province was used. A retrospective investigation was performed in 2015. The effects of SBP and DBP on the all-cause mortality were analyzed using the Cox regression model. The hazard ratio (HR) and 95% confidence interval (CI) were estimated by the sex and age groups. Results The follow-up rate was 76.52% over 13 years, while the cumulative mortality rate for all participants was 917.12/100,000 person-years. The mortality rose with an increasing SBP (chi(2)(trend) = 270.537, P < 0.001) or DBP level (chi(2)(trend) = 57.240, P < 0.001). After adjustment for the confounding factors, a significant association between mortality and high SBP (>= 160 mmHg) and high DBP (>= 100 mmHg), with adjusted HR ranging from 1.405- to 2.179-fold for SBP and 1.550- to 2.854-fold for DBP, was noted. Significant HRs for most DBP subgroups were found in > 60-year-old participants. Males with DBP >= 100 mmHg had a significantly higher mortality, with an HR (95% CI) of 2.715 (1.377-5.351). Conclusion Adults with SBP > 160 mmHg and DBP > 100 mmHg had a higher mortality risk. Sex and age difference was noted in both DBP and mortality risk.