Antithrombotic therapy and recurrence requiring surgery after twist-drill craniostomy for first-time chronic subdural hematoma

Background Chronic subdural hematoma (cSDH) predominantly affects older and medically frail patients, many of whom receive antithrombotic therapy. Recurrence requiring surgery is a major concern in this population and the effect of antithrombotic therapy on recurrence remains debated. We investigated the association between antithrombotic therapy at presentation and reoperation after twist-drill craniostomy (TDC). Methods We retrospectively reviewed first-time TDC with subdural drain for cSDH between 2018 and 2025 at a tertiary referral center. Antithrombotics were categorized as none, antiplatelet therapy, vitamin K antagonist (VKA), direct oral anticoagulant (DOAC), or dual antithrombotics. Antithrombotics were discontinued at presentation and managed according to a perioperative reversal protocol. The primary endpoint was reoperation for recurrent or residual ipsilateral cSDH within three months. Multivariable logistic regression was adjusted for age, sex, laterality, and hematoma membrane was performed. Results Among 924 first-time TDC, 279 (30.2%) required reoperation. Reoperation rates were 25.6% without antithrombotic therapy, 29.3% with antiplatelet therapy, 32.2% with VKA, 42.4% with DOAC, and 62.5% with dual antithrombotic therapy. After adjustment, VKA (OR 2.01, 95% CI 1.13–3.54; p = 0.016), DOAC (OR 1.68, 95% CI 1.00–2.81, p = 0.048), and dual antithrombotic therapy (OR 4.56, 95% CI 1.85–11.88; p = 0.001) were independently associated with higher odds of reoperation, antiplatelet therapy was not. Conclusions In this cohort of 924 first-time TDC for cSDH, anticoagulation, particularly dual antithrombotic therapy, was associated with higher odds of recurrence requiring reoperation. These patients may warrant closer postoperative surveillance and tailored surgical and follow-up strategies.