Objective:

To test the hypothesis that the response to intensive BP reduction is different among patients with deep and lobar intracerebral hemorrhages (ICH).

Background:

Blood pressure (BP) reduction is associated with better neuroimaging and clinical outcomes in patients with spontaneous, non-traumatic ICH. Because this evidence comes from studies that overwhelmingly enrolled deep hemorrhages, the impact of BP reduction in patients with lobar ICH remains understudied.

Design/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.

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 in 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, p=0.83 and RAE, p=0.53). Intensive BP reduction was not associated with improved mRS in either location group (p > 0.05).

Conclusions:

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.