Contribution of Racial and Ethnic Differences in Cerebral Small Vessel Disease Subtype and Burden to Risk of Cerebral Hemorrhage Recurrence
Objective:Black and Hispanic survivors of Intracerebral Hemorrhage (ICH) are at higher risk of recurrent intracranial bleeding. MRI-based markers of chronic Cerebral Small Vessel Disease (CSVD) are consistently associated with recurrent ICH. We therefore sought to investigate whether racial/ethnic differences in MRI-defined CSVD subtype and severity contribute to disparities in ICH recurrence risk.Methods:We analyzed data from the Massachusetts General Hospital ICH study (MGH-ICH, n=593) and the ERICH (Ethnic/Racial Variations of Intracerebral Hemorrhage) study (n= 329). Using CSVD markers derived from MRIs obtained within 90 days of index ICH, we classified ICH cases as cerebral amyloid angiopathy (CAA)-related, hypertensive arteriopathy (HTNA)-related, and mixed etiology. We quantified CSVD burden using validated global, CAA-specific, and HTNA-specific scores. We compared CSVD subtype and severity among White, Black, and Hispanic ICH survivors and investigated its association with ICH recurrence risk.Results:We analyzed data for 922 ICH survivors (655 White, 130 Black, 137 Hispanic). Minority ICH survivors had greater global CSVD (p=0.011) and HTNA burden (p=0.021) on MRI. Furthermore, minority survivors of HTNA-related and mixed etiology ICH demonstrated higher HTNA burden, resulting in increased ICH recurrence risk (all p < 0.05).Conclusions:We uncovered significant differences in CSVD subtypes and severity among White and minority survivors of primary ICH, with direct implication for known disparities in ICH recurrence risk. Future studies of racial / ethnic disparities in ICH outcomes will benefit from including detailed MRI-based assessment of CSVD subtypes and severity, and investigating social determinants of health.