Association between intensive blood pressure lowering and stroke-free survival among patients with and without Diabetes.

ABSTRACT

This study pooled data from SPRINT (Systolic Blood Pressure Intervention Trial) and ACCORD-BP (Action to Control Cardiovascular Risk in Diabetes Blood Pressure) trial to estimate the treatment effect of intensive BP on stroke prevention, and investigate whether stroke risk score impacted treatment effect. Of all the potential manifestations of the hypertension, the most severe outcomes were stroke or death. A composite endpoint of time to death or stroke (stroke-free survival [SFS]), whichever occurred first, was defined as the outcome of interest. Participants without prevalent stroke were stratified into stroke risk tertiles based on the predicted revised Framingham Stroke Risk Score. The stratified Cox model was used to calculate the hazard ratio (HR) for the intensive BP treatment. 834 (5.92%) patients had SFS events over a median follow-up of 3.68 years. A reduction in the risk for SFS was observed among the intensive BP group as compared with the standard BP group (HR 0.76, 95% CI 0.65, 0.89; risk difference 0.98([0.20, 1.76]). Further analyses demonstrated the significant benefit of intensive BP treatment on SFS only among participants having a high stroke risk (risk tertile 1 0.76 [0.52, 1.11], number needed to treat [NNT] = 861; risk tertile 2 0.87[0.65, 1.16], NNT = 91; risk tertile 3 0.69[0.56, 0.86], NNT = 50). Intensive BP treatment lowered the risk of SFS, particularly for those at high risk of stroke.