Level 2: Mid-level evidence
BP control is important for reducing risk of cardiovascular events, but the optimal BP level in many clinical scenarios is unknown. To identify the BP ranges associated with lowest cardiovascular risk in patients with prior acute coronary syndromes, researchers performed a post-hoc analysis of the PROVE IT-TIMI 22 trial (Circulation. 2010;122:2142-2151). Patients were grouped by average BP readings achieved during the trial. Average readings outside of the ranges of 130-140 mm Hg systolic and 80-90 mm Hg diastolic had an increased risk of future cardiovascular events. A total of 4,162 patients hospitalized for acute coronary syndrome and receiving a statin were evaluated for the effect of BP range on a composite outcome of all-cause mortality, MI, unstable angina requiring rehospitalization, revascularization after 30 days, and stroke.
During a mean follow-up of 24 months, 24% of patients reached the composite outcome. BPs outside of the range of 130-140 systolic and 80-90 diastolic were associated with an increased risk of the composite outcome. Compared with patients in these BP ranges, patients with significantly elevated BP (systolic >160 or diastolic >100) had 3.7- to 4.9-fold increased risk. The risk was also elevated for patients with low BP (≤100 systolic, ≤60 diastolic), with a 1.2- to 2.1-fold increased risk of the composite outcome. The BP associated with lowest risk was 136/85 (P <0.0001). Similar findings were observed for a composite outcome of death due to coronary heart disease, nonfatal MI or revascularization, and for individual outcomes of all-cause mortality, cardiovascular mortality, and nonfatal MI.