Abstract 97: Ischemic Lesions in Intracerebral Hemorrhage Associated with Drop in Blood Pressure and Poor Outcomes in the ERICH Study

Abstract

Background: Up to 1/3 of patients with primary intracerebral hemorrhage (ICH) have acute ischemic lesions remote from the hematoma visualized on diffusion-weighted MRI (DWI). Prior reports associated these lesions with large blood pressure fluctuations in the acute hospital setting. Here, the Ethnic/Racial variations of Intracerebral Hemorrhage (ERICH) study explored predictors of ischemic lesions in primary ICH and their impact on long-term outcomes. Methods: ERICH is a multi-center, prospective study of ICH among white, black, and Hispanic patients. At least every 5th patient undergoes a study MRI interpreted by a central core blinded to clinical data. We calculated change in mean arterial pressure (delta MAP) by taking the difference in highest and lowest blood pressure prior to MRI. Results: For the 601 cases with a DWI MRI, mean±SD age was 61±14 years, mean ICH volume was 16±18 cc, 55% were male, 79% had hypertension and 26% had ≥1 DWI lesions. The frequency of DWI lesions differed by ethnicity (blacks 33%, Hispanics 24%, whites 20%, overall p=0.005). The multivariable logistic regression analysis identified lower age (10 year OR=0.68, p<0.001), higher delta MAP (10 unit OR=1.16, p<0.001), higher WMD score (1 unit OR=1.164, p<0.001) and presence of microbleeds (OR=2.122, p=0.001) as predictors of DWI lesions. After controlling for age, ICH volume, IVH and admission GCS, presence of DWI lesions was associated with 6 month poor outcome (MRS 4-6, OR=1.25, p=0.02; Figure). Conclusions: The ERICH study confirms that large fluctuations in blood pressure during the acute hospitalization period predict DWI lesions, and that DWI lesions predict poor outcomes. We hypothesize that substantial reductions in blood pressure precipitate acute small vessel ischemia in those ICH patients with a more severe underlying diseased vasculature. Further studies are needed to determine whether there is a level of acute blood pressure reduction at which the risks outweigh the benefits.