INTERACT-2

Abstract

Blood pressure (BP) lowering after spontaneous intracerebral hemorrhage (ICH) is intuitively attractive as a means to prevent continued bleeding or perihematomal edema. Concerns about potential reduction of cerebral perfusion pressure with concomitant risk of ischemia, particularly among patients with a recalibrated autoregulatory curve as a consequence of chronic hypertension, were largely mitigated by imaging studies that found no significant reduction of cerebral blood flow in the face of pharmacological BP lowering,1–3 and the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT) pilot study.4 The INTERACT investigators have now formally put the concept to test and have shown that if there is a clinical effect of BP lowering, it is fairly muted and smaller than anticipated. Of 2794 patients with spontaneous ICH, the relative risk for poor outcome was 0.94 (0.87–1.002), P =0.063, in the intensive BP-lowering group (to target systolic pressure ≤140 mm Hg) compared with the control guideline group aiming for systolic pressure ≤180 mm Hg. Various permutations of modified Rankin Scale dichotomization were also nonsignificant when adjusted for baseline factors. The Rankin shift analysis using ordinal logistic regression was marginally significant in favor of the intensive BP-lowering group ( P =0.04). Importantly, no differences in mortality and major safety …