Christopher B. Anderson

Background: Hypertension is the most potent modifiable risk factor for recurrent intracerebral hemorrhage (ICH), yet blood pressure (BP) control after ICH remains suboptimal, particularly among disadvantaged racial and socioeconomic groups. To what extent post-ICH BP disparities reflect pre-existing hypertension inequities versus differences in post-ICH management is unknown. We examined disparities in BP control before and after ICH, assessed whether post-ICH care differentially improves BP across groups and whether post-ICH disparities persist after accounting for pre-existing BP differences. Methods: We performed a case-only study in the All of Us Research Program, identifying ICH survivors using electronic health record diagnosis codes. Mean systolic BP was calculated for pre-ICH (1–365 days before) and post-ICH (30–365 days after) windows. Neighborhood deprivation tertiles were calculated using 3-digit ZIP codes. The primary outcome was uncontrolled BP (≥140 mmHg). Logistic regression estimated odds of uncontrolled BP, and mediation analysis estimated the proportion of post-ICH disparities explained by pre-ICH BP. Results: Among 2,226 ICH survivors (mean age 60; 50.6% female), 1,760 had pre-ICH and 1,852 had post-ICH BP data. Uncontrolled BP was more common in Black than White survivors both pre-ICH (38.9% vs 21.4%; p<0.001) and post-ICH (34.3% vs 16.3%; p<0.001), and in Deprived versus Privileged neighborhoods post-ICH (23.7% vs 15.8%; p<0.001). In adjusted models, Black race (OR 3.51; 95% CI 2.55–4.83; p<0.001) and Deprived neighborhoods (OR 1.38; 95% CI 1.00–1.91; p=0.048) were associated with uncontrolled post-ICH BP. Among survivors uncontrolled before ICH, 67% of White but only 45% of Black survivors achieved control afterward (p=0.001). Adjusting for pre-ICH BP control status only modestly attenuated the Black-White disparity (OR 4.05 to 2.95; P<0.001). In mediation analyses, pre-ICH BP explained only 27% of the racial (P<0.001) and 26% of the deprivation (P=0.014) disparity. Conclusions: Racial and socioeconomic disparities in BP control persist after ICH, but most post-ICH disparities are not explained by pre-existing inequalities. More advantaged populations achieve greater BP improvement, suggesting effective post-ICH management exists but does not reach all patients equitably. Targeted interventions addressing barriers to post-ICH BP control in disadvantaged populations may substantially reduce persistent disparities.