Relation of blood pressure components and categories and all-cause, stroke and coronary heart disease mortality in urban Chinese women: a population-based prospective study

Abstract
Objective To determine whether various levels of blood pressure (BP), particularly normal and high normal BP or prehypertension, predict cardiovascular mortality among urban Chinese women. Methods We evaluated the impact of all measures of BP on total mortality and stroke and coronary heart disease (CHD)-specific mortality in a population-based cohort study, the Shanghai Women's Health Study. Included in this analysis were 68 438 women aged 40–70 years at baseline for whom BP was assessed. Results During an average of 5 years of follow-up, we identified 1574 deaths from all causes, 247 from stroke and 91 from CHD. Hypertension and higher levels of individual BP parameters including systolic BP, diastolic BP, pulse pressure, and mean arterial pressure were positively associated with all-cause, stroke, and CHD mortality (Ptrend < 0.05 for all except for DBP and CHD mortality). Prehypertension [adjusted hazard ratio (HRadj) = 1.65; 95% confidence interval, 0.98–2.78], particularly high normal BP (HRadj = 2.34; 95% confidence interval, 1.32–4.12), was associated with an increased risk of mortality from stroke. Hypertension accounted for 9.3% of mortality from all causes, 25.5% of mortality from stroke, and 21.7% mortality from CHD. High normal BP accounted for 10.8% of mortality from stroke. Isolated systolic BP also predicted stroke and mortality from CHD. Conclusion Hypertension is a significant contributor to mortality, particularly stroke and CHD mortality, among women in Shanghai. High normal BP is associated with high stroke mortality.