Influence of Antiplatelet Therapy on Postoperative Recurrence of Chronic Subdural Hematoma: a Multicenter Retrospective Study in 719 Patients

Objective: The present study tested the hypothesis of whether antiplatelet agents (APA) induce chronic subdural hematoma (CSDH) recurrence via a platelet aggregation inhibitory effect.

Method: We examined risk factors for CSDH recurrence, focusing on APA, in 719 consecutive patients who admitted to three tertiary hospitals and underwent burr-hole craniostomy and irrigation for CSDH. This was a multicenter, retrospective, observational study.

Results: Age, sex, history of diabetes mellitus, hypertension, chronic renal failure, alcohol consumption habits, consciousness disturbance on admission, or preoperative CT density was not associated with recurrence. Subdural drainage was significantly associated with less recurrence. Preoperative oral APA administration was significantly associated with more recurrence. The recurrence rate of CSDH in non-APA group was 11% if surgery was performed on admission. However, if surgery was performed immediately after discontinuation of oral APA administration, the recurrence rate in APA group significantly increased to 32% (p value<0.0001; odds ratio, 3.77; 95% confidence interval, 1.72-8.28). The effect of APA on CSDH recurrence gradually diminished as the number of days until initial surgery, after stopping APA, increased.

Conclusion: Antiplatelet therapy significantly influences the recurrence of CSDH.