Impact of achieved blood pressure on first stroke in uncomplicated grade 1 hypertension

Abstract

Background-We aimed to test the impact of achieved blood pressure (BP) on first stroke among patients with grade 1 hypertension and without cardiovascular diseases in the China Stroke Primary Prevention Trial. Methods and Results-A total of 3187 patients with uncomplicated grade 1 hypertension were included. The risk of outcomes was assessed according to: (1) the proportion of visits in which BP was reduced to < 140/90 mm Hg, and (2) the time-averaged systolic BP (SBP) or diastolic BP levels during the study treatment period. The median antihypertensive treatment duration was 4.6 years. Only 1.5% of the participants discontinued the treatments because of adverse reaction. Overall, the risk of stroke decreased with the increase of the proportion of study visits with BP < 140/90 mm Hg (for per 5% increase; hazard ratio, 0.92 [95% CI, 0.87-0.98]). Consistently, compared with patients with time-averaged SBP≥140 or diastolic BP≥90 mm Hg, the risk of stroke was lower in patients with time-averaged SBP of 120 to < 140 mm Hg (1.1% versus 2.9%; hazard ratio, 0.39 [95% CI, 0.22-0.69]) or diastolic BP < 90 mm Hg (1.5% versus 2.7%; hazard ratio, 0.41 [95% CI, 0.17-0.98]). The beneficial results were consistent across age (< 60 versus ≥60 years), sex, baseline SBP (< 150 versus 150 to < 160 mm Hg), study treatment groups (enalapril or enalaprilfolic acid), and hypertension subtypes (isolated systolic hypertension or systolic-diastolic hypertension). However, a time-averaged SBP < 120 mm Hg (versus 120-140 mm Hg) was associated with an increased risk for stroke. Similar results were observed for composite cardiovascular events or all-cause death. Conclusions-Achieved BP < 140/90 mm Hg was significantly associated with a decreased risk of stroke or all-cause death in patients with uncomplicated grade 1 hypertension.