Abstract 149: Different Response to Blood Pressure Reduction in Lobar and Deep Intracerebral Hemorrhage

Abstract

Background: Blood pressure (BP) reduction is associated with better neuroimaging and clinical outcomes in patients with spontaneous, non-traumatic intracerebral hemorrhage (ICH). Because this evidence comes from studies that overwhelmingly enrolled deep hemorrhages, the impact of BP reduction in patients with lobar ICH remains understudied. Methods: We re-analyzed data from the pivotal Antihypertensive Treatment of Acute Cerebral Hemorrhage-2 (ATACH-2) study. We included all patients with available neuroimaging data. Participants were randomized to either intensive (systolic BP target 110-139 mmHg) or standard (systolic BP target 140-179 mmHg) acute BP lowering. The main outcome measures were hematoma expansion > 6 mL in the first 24 hours (HE), poor functional outcome (3-month mRS 4-6) and renal adverse events (RAE) until day 7 or hospital discharge. We fitted multivariable logistic regression models to test for association between the intervention and our outcomes of interest. Covariates included sex, age, race and ethnicity, and baseline ICH volume. Results: Among 1,000 patients enrolled in ATACH-2, 875 (87.5%) with complete data were included (88.9% deep hemorrhages and 11.1% lobar hemorrhages). The baseline characteristics of the intensive and standard treatment groups remained balanced as in the original study (all comparisons p >0.05). Multivariable logistic regression showed that intensive BP reduction decreased the risk of HE (OR 0.60, 95%CI 0.39-0.90; p=0.02) and increased the risk of RAE (OR 2.53, 95%CI 1.40-4.77; p=0.003) in patients with deep, but not lobar ICH (HE, OR: 0.89; 95% CI= 0.31 - 2.52; p=0.83 and RAE, OR: 0.46; 95% CI= 0.04 - 5.10; p=0.53). Intensive BP reduction was not associated with improved mRS in either deep (OR: 0.96; 95 % CI= 0.68 - 1.37; p= 0.82) nor lobar (OR: 0.66; 95% CI= 0.16 - 2.42; p= 0.54) ICH. Conclusion: The impact of intensive blood pressure lowering differs in deep and lobar ICH. These results emphasize the need for a better understanding about biologic differences in ICH, which may have therapeutic implications.