Regional Differences in the Response to Acute Blood Pressure Lowering After Cerebral Hemorrhage

Abstract

Objective: To compare the impact of intensive blood pressure (BP) lowering right after intracerebral hemorrhage (ICH) on clinical and hematoma outcomes among patients from different geographic locations, we performed a prespecified subanalysis of a randomized, multinational, 2-group, open-label trial to determine the efficacy of rapidly lowering BP in hyperacute ICH (Antihypertensive Treatment of Acute Cerebral Hemorrhage [ATACH]-2), involving 537 patients from East Asia and 463 recruited outside of Asia.

Methods: Eligible patients were randomly assigned to a systolic BP target of 110 to 139 mm Hg (intensive treatment) or 140 to 179 mm Hg (standard treatment). Predefined outcomes were poor functional outcome (modified Rankin Scale score 4-6 at 90 days), death within 90 days, hematoma expansion at 24 hours, and cardiorenal adverse events within 7 days.

Results: Poor functional outcomes (32.0% vs 45.9%), death (1.9% vs 13.3%), and cardiorenal adverse events (3.9% vs 11.2%) occurred significantly less frequently in patients from Asia than those outside of Asia. The treatment-by-cohort interaction was not significant for any outcomes. Only patients from Asia showed a lower incidence of hematoma expansion with intensive treatment (adjusted relative risk [RR] 0.56, 95% confidence interval [CI] 0.38-0.83). Both Asian (RR 3.53, 95% CI 1.28-9.64) and non-Asian (RR 1.71, 95% CI 1.00-2.93) cohorts showed a higher incidence of cardiorenal adverse events with intensive treatment.

Conclusions: Poor functional outcomes and death 90 days after ICH were less common in patients from East Asia than those outside of Asia. Hematoma expansion, a potential predictor for poor clinical outcome, was attenuated by intensive BP lowering only in the Asian cohort.

Clinicaltrialsgov identifier: NCT01176565.

Classification of evidence: This study provides Class II evidence that, for patients from East Asia with ICH, intensive blood pressure lowering significantly reduces the risk of hematoma expansion.