Determinants and prognostic significance of hematoma sedimentation levels in acute intracerebral hemorrhage

Background: This study aimed at identifying the determinants and prognostic significance of a sedimentation level (fluid-blood level) in the hematoma among patients with acute intracerebral hemorrhage (ICH) who participated in the main Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2). Methods: Post-hoc analysis of the INTERACT2 dataset, a randomized controlled trial of patients with acute ICH with elevated systolic blood pressure (SBP), randomly assigned to intensive (target SBP <40 mm Hg) or guideline-based (<180 mm Hg) BP management. Patients with a sedimentation level at baseline assessment on CT, and modified Rankin Scale score at 90-day, were included in these analyses. Factors associated with a sedimentation level and its significance in relation to 90-day clinical outcomes were assessed in univariable and multivariable logistic regression models. Results: Of 2,065 participants, 19 (1%) had sedimentation level on baseline CT, which was independently associated with warfarin use (p = 0.006) and lobar ICH (p = 0.025). Sedimentation level was also associated with death or major disability at 90-day in both crude (84 vs. 53%; p = 0.014) and multivariable analyses adjusted for age, gender, Chinese region, warfarin use, baseline National Institutes of Health Stroke Scale score, onset to CT time, volume and location of ICH, intraventricular extension, and randomized intensive BP lowering (OR 3.94, 95% CI 1.01-15.37; p = 0.049). Conclusions: The presence of hematoma sedimentation level on baseline CT is associated with warfarin use and lobar location of ICH, and predicts a worse outcome. Although uncommon, sedimentation level is an easily detectable prognostic factor in acute ICH.