Subarachnoid Extension of Intracerebral Hemorrhage and 90-Day Outcomes in INTERACT2

Background and Purpose The prognostic significance of subarachnoid extension of intracerebral hemorrhage was determined in the INTEnsive blood pressure Reduction in Acute Cerebral hemorrhage Trial (INTERACT2) study. Methods INTERACT2 was an open randomized controlled trial of early intensive compared with guideline-recommended blood pressure lowering in patients with elevated systolic blood pressure within 6 hours of intracerebral hemorrhage. Independent predictors of death or major disability (scores 3-6 on the modified Rankin Scale) at 90 days were analyzed in logistic regression models. Results Of 2582 participants, 192 (7%) had subarachnoid extension, which was associated with larger hematoma volumes (P<0.0001) and higher National Institute of Health Stroke Scale score (P<0.0001). Subarachnoid extension predicted death or major disability at 90 days (71% versus 53%; unadjusted odds ratio, 2.25; 95% confidence interval, 1.63-3.10; P<0.0001). The association remained significant after adjusting for age, region, lipid-lowering therapy, systolic blood pressure, glucose, location of hematoma, intraventricular extension, and randomized treatment (odds ratio, 2.17; 95% confidence interval, 1.50-3.14; P<0.0001), but not after further adjustment for baseline hematoma volume (P=0.62). Conclusions Subarachnoid extension of intracerebral hemorrhage is associated with poor prognosis, which is determined by a larger volume of the underlying intraparenchymal hematoma. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00716079.