Resumption of Antiplatelet Therapy After Burr‐Hole Surgery and Recurrence in Patients With Chronic Subdural Hematoma: A Target Trial Emulation

PURPOSE: Clinicians are often concerned that early resumption of antiplatelet therapy may increase the risk of recurrence after burr-hole surgery for chronic subdural hematoma (CSDH), yet studies on this issue remain limited. We evaluated whether early resumption of antiplatelet therapy increases CSDH recurrence using a target trial emulation framework. METHODS: We identified patients who had received antiplatelet therapy preoperatively and undergone initial burr-hole surgery for CSDH from two hospital-based administrative databases (2016-2024). To estimate CSDH recurrence risk with early resumption, we compared two treatment strategies: strategy 1, resumption of antiplatelet therapy within 4 days after the initial burr-hole surgery; and strategy 2, no resumption within 30 days after the initial burr-hole surgery. We employed the clone-censor-weight method to address immortal time and time-varying confounders. Using a stabilized weighted pooled logistic regression model, we then calculated the 30-, 60-, and 90-day risk of CSDH recurrence. RESULTS: Among 1552 eligible patients, 217 (14.0%) experienced CSDH recurrence within 90 days. Risk of CSDH recurrence at 30, 60, and 90 days was 8.1%, 13.7%, and 14.2% for strategy 1 versus 7.2%, 12.5%, and 13.9% for strategy 2. The respective risk ratios were 1.13 (95% CI, 0.76-1.56), 1.10 (0.75-1.51), and 1.02 (0.71-1.40), and the risk differences were 0.9% (-2.2 to 3.4), 1.2% (-3.7 to 5.2), and 0.3% (-4.8 to 4.6). CONCLUSIONS: This study suggests that early resumption of antiplatelet therapy may not increase CSDH recurrence risk. These findings may inform clinical decision-making regarding postoperative antiplatelet management.