Peripheral monocyte count is associated with hematoma clearance after intracerebral hemorrhage: a multicenter...

Accelerating hematoma clearance after intracerebral hemorrhage (ICH) can reduce secondary brain injury. However, factors influencing hematoma resolution rate remain unclear in ICH patients. This study aimed to identify predictors of the hematoma clearance rate and determine its association with short-term functional outcomes in ICH patients. Multicenter consecutive ICH patients from 2020 to 2021 were retrospectively analyzed. We included subjects with a follow-up computed tomographic scan available within 15 ± 4 days and without recurrent bleeding or hematoma expansion after admission. Hematoma volumes were calculated by ABC/2 method, with regions exceeding 50 Hounsfield Units (HU) defined as hematoma. Multiple linear regression and multiple logistics regression were used to identify factors affecting the hematoma clearance rate. The association between the hematoma clearance rate and 3-month functional outcome was investigated with multivariate logistic regression. 1273 patients were screened and 116 subjects met eligibility criteria (median age, 57.3 years; 72.4% men). Peripheral monocyte count (OR: 2.00; 95% CI: 1.26-3.16; P = 0.003) and admission hematoma volume (OR: 1.36; 95% CI: 1.19-1.54; P < 0.001) was associated with the rate of hematoma clearance. However, the hematoma clearance rate was not significantly associated with short-term prognosis (OR: 1.23; 95% CI: 0.2-7.67; P = 0.823). Elevated levels of peripheral monocyte count and hematoma volume were independently related to the rate of hematoma clearance. The relationship between the rate of hematoma clearance and short-term outcomes in ICH patients has not been demonstrated. Modulating peripheral monocytes might represent a potential therapeutic target for regulating hematoma resolution in the future.