Effect of platelet-activating factor receptor antagonist, etizolam, on resolution of chronic subdural hematoma--a prospective study to investigate use as conservative therapy.

Inflammatory reaction is very important for formation of the neomembrane of chronic subdural hematoma (CSDH). The present study evaluated medical treatment with the platelet-activating factor receptor antagonist, etizolam, for the resolution of CSDH, and the factors indicating surgery or conservative therapy. Alternate patients were assigned to the etizolam group or control group without medical treatment. Patients in the etizolam group received 3.0 mg etizolam per day for 14 days. A total of 53 patients were followed up for at least 6 months. Univariate analysis of differences in demographic characteristics, clinical findings, and initial computed tomography (CT) findings, and multiple logistic regression analysis of the relationship between etizolam treatment and requirement for surgery using age, sex, low density of hematoma on CT, and paresis as confounders were performed. Etizolam treatment (adjusted odds ratio [OR] 0.156, 95% confidence interval [CI] 0.024-0.999, p = 0.049) was negatively correlated with requirement for surgery. Low density of hematoma (adjusted OR 0.125, 95% CI 0.019-0.846, p = 0.033) was found to be an independent negative predictor, and paresis as an initial symptom (adjusted OR 6.35, 95% CI 1.04-38.7, p = 0.045) was an independent positive predictor of requirement for surgery. Etizolam administration can promote the resolution of CSDH, especially at the stage of hygroma appearing as low density on CT. Surgery is recommended if the patient presents with paresis.