Consistency of Blood Pressure Control After Ischemic Stroke

Abstract

Background and Purpose— Blood pressure (BP) reduction lowers vascular risk after stroke; however, little is known about the relationship between consistency of BP control and risk of subsequent vascular events. Methods— In this post hoc analysis of the Vitamin Intervention for Stroke Prevention trial (n=3680), individuals with recent (<120 days) stroke, followed up for 2 years, were divided according to proportion of visits in which BP was controlled (<140/90 mm Hg): <25%, 25% to 49%, 50% to 74%, and ≥75%. Multivariable models adjusting for demographic and clinical variables determined the association between consistency of BP control versus primary (stroke) and secondary (stroke, myocardial infarction, or vascular death) outcomes. Results— Only 30% of participants had BP controlled ≥75% of the time. Consistency of BP control affected outcomes in individuals with baseline systolic BP >132 mm Hg. Among individuals with baseline systolic BP >75th percentile (>153 mm Hg), risks of primary and secondary outcomes were lower in those with BP controlled ≥75% versus <25% of visits (adjusted hazard ratio, 0.46; 95% confidence interval, 0.26–0.84 and adjusted hazard ratio, 0.51; 95% confidence interval, 0.32–0.82). Individuals with mean follow-up BP <140/90 mm Hg had lower risk of primary and secondary outcomes than those with BP ≥140/90 mm Hg (adjusted hazard ratio, 0.76; 95% confidence interval, 0.59–0.98 and adjusted hazard ratio, 0.76; 95% confidence interval, 0.62–0.92). Conclusions— In this rigorous clinical trial, fewer than one third of patients with stroke had BP controlled ≥75% of the time for 2 years. Furthermore, consistency of BP control among those with elevated baseline systolic BP was linked to reduction in risk of recurrent stroke and stroke, myocardial infarction, and vascular death.