Abstract 3729: Delayed Hematoma Expansion Occurs After ICH: Observations from the Safety of Pioglitazone for Hematoma Resolution in INtraCerebral Hemorrhage (SHRINC) trial

Background and Purpose Early hematoma expansion (EHE) has been described in the first 48 hours. SHRINC is a phase 2 prospective safety trial whose primary objective is to assess the safety of pioglitazone (PIO) when administered to patients with spontaneous intracerebral hemorrhage (SICH) compared to standard care. A secondary objective is to characterize the changes in hematoma resolution and expansion over time. This prospective study addresses the natural history, clinical impact, and associated risk factors of late hematoma expansion (LEX) by serial magnetic resonance imaging (MRI) after SICH. Methods SHRINC aims to enroll 78 subjects between the ages of 18-80 with a SICH of ≥ 5 ml. This analysis includes the first 42 patients enrolled. Four subjects were excluded because they did not have an MRI after day 2. A baseline CTH was performed followed by an MRI within 24 hours of symptom onset. Hematoma volume (Hv) was measured on FLAIR sequences using a previously published semi-automated range of interest method. LEX was defined as an increase in Hv > 0.5 ml after the 48 hour MRI. Factors associated with LEX were evaluated with logistic regression. Longitudinal analyses were used for measurements taken over the follow up period. Results: Ten (26.3%) of 38 subjects displayed LEX. Eight subjects had LEX between day 2 to 14, and 4 between days 14 to 28. The median initial Hv was 16.1cc in LEX patients and 24.1cc in those without expansion (NEX) (p=0.23). Lower platelet counts (p=0.04) and BUN levels (p=0.03) were associated with LEX in univariate analysis. Multivariate analysis suggested that those with higher BUN levels were less likely to have LEX (OR=0.81; 95%CI 0.65-0.99). Blood pressure and EHE (13.2%) were not associated with LEX. There was no difference in neurological worsening (NIHSS increase ≥ 4), 6 month mRS or death between LEX and NEX. Conclusion: This is the first prospective study to address LEX with serial MRIs. LEX occurs between day 2 to 14 and day 14 to 28. Elevated BUN levels may decrease the likelihood of LEX. A limitation of our study is that the effect of PIO on LEX could not be evaluated because SHRINC is a blinded trial. Further studies will assess the pathophysiology of LEX and its potential implications in clinical trials evaluating hematoma growth and resolution.