Risk factors for intracerebral hemorrhage: the REasons for geographic and racial differences in stroke (REGARDS) study

Abstract

Background and purpose: Risk factors for intracerebral hemorrhage (ICH) have been largely identified in case-control studies, with few longitudinal studies available.

Methods: Predictors of incident ICH among 27 760 black and white participants from the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort study were assessed.

Results: There were 62 incident ICH events during an average follow-up of 5.7 years. The increase in risk with age differed substantially between blacks and whites (P=0.006), with a 2.25-fold (95% confidence interval, 1.63-3.12) increase per decade in whites, but no age association with ICH risk in blacks (hazard ratio=1.09; 95% confidence interval, 0.70-1.68). We observed increased risk among men, those with higher systolic blood pressure, and warfarin users.

Conclusions: The racial differences in the impact of age contributed to a risk of ICH that was >5 times higher for blacks than whites at age 45, but only about one third as great by age 85. Confirming findings from other studies, men participants with elevated systolic blood pressure and warfarin users were also at greater risk. The contributors to the racial differences in ICH risk require additional investigation.

Figures

Figure 1

AA-to-white hazard ratio (and 95% confidence interval) for intracerebral hemorrhage as a function of age after adjustment for sex, systolic blood pressure and warfarin use