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 enalapril‐folic 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.