Comparing hematoma characteristics in primary intracerebral hemorrhage versus intracerebral hemorrhage caused by structural vascular lesions

Intracerebral hemorrhage (ICH) caused by structural vascular lesions is associated with better outcomes than primary ICH, but this relationship is poorly understood. We tested the hypothesis that ICH from a vascular lesion has more benign hematoma characteristics compared to primary ICH. We performed a retrospective study using data from our medical center. The SMASH-U criteria were used to adjudicate the etiology of ICH. The co-primary outcomes were admission parenchymal hematoma volume and hematoma expansion at 24 h. Linear and logistic regression analyses were performed to test associations. A total of 231 patients were included of whom 42 (18%) had a vascular lesion. Compared to primary ICH patients, those with structural vascular lesions were younger (49 vs. 68 years, p < 0.001), less likely to have hypertension (29% vs. 74%, p < 0.001), had lower mean admission systolic blood pressure (140 +/- 23 vs. 164 +/- 35, p < 0.001), less frequently had IVH (26% vs. 44%, p = 0.03), and had mostly lobar or infratentorial hemorrhages. The median admission hematoma volume was smaller with vascular lesions (5.9 vs. 9.7 mL, p = 0.01). In regression models, ICH from a vascular lesion was associated with smaller admission hematoma volume (beta,-0.67, 95% CI,-1.29 to-0.05, p = 0.03), but no association with hematoma expansion was detected when assessed as a continuous (OR, 0.93; 95% CI,-4.46 to 6.30, p = 0.73) or dichotomous exposure (OR, 1.86; 95% CI, 0.40 to 8.51, p = 0.42). In a single-center cohort, patients with ICH from vascular lesions had smaller hematoma volumes than patients with primary ICH.