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.

Keywords: achieved blood pressure; all‐cause death; cardiovascular disease prevention; grade 1 hypertension; high blood pressure; hypertension; primary prevention; stroke.