Article Citation: Kamenova M, Pacan L, Mueller C, et al. Aspirin Continuation or Discontinuation in Surgically Treated Chronic Subdural Hematoma: A Randomized Clinical Trial. JAMA Neurol. 2025;82(6):551-

Background: There is uncertainty regarding whether aspirin should be continued in patients with chronic subdural hematoma (cSDH) who undergo surgical evacuation. The risk of bleeding in the setting of aspirin use should be weighed against the risk of cardiovascular events in the setting of aspirin discontinuation.

Methods: Surgical Evacuation of Chronic Subdural Hematoma and Aspirin (SECA) is a multicenter, randomized, double-blind clinical trial including six participating neurosurgical centers in Switzerland. Eligible patients were adults with symptomatic cSDH receiving aspirin and requiring burr hole intervention. Patients were excluded if burr hole drainage was not sufficient and additional surgical intervention was pursued. Other exclusion criteria included significant cardiac events or bleeding events in the 30 days preceding randomization. Patients on additional antithrombotic agents were not excluded from the trial, and reversal approach was detailed in the study protocol. Trial participants were randomized to 100mg/day aspirin or placebo for 12 days in a double-blind approach. The 12 treatment days occurred at different times in relation to the urgency of surgery. Administration of study medication started on postoperative day one for emergent cases; preoperatively for urgent cases where surgery was scheduled 24 hours after the patient’s last aspirin dose; and five days prior to surgery for elective cases. After the 12-day treatment course, patients were continued on aspirin. Recurrence of chronic symptomatic SDH requiring surgical intervention within six months was the primary outcome. Rates of recurrent but non-operative SDH were not reported.

Results: 155 patients were included in the final analyses (77 in the placebo arm and 78 in the aspirin group).  The patients were predominately male (83.1% in the placebo and 84.6% in the aspirin group), and of similar mean age (77.6 vs. 77.9 years old). A primary outcome event of recurrent symptomatic SDH requiring surgical intervention within 6 months was seen in 13.9% vs. 9.5% in the placebo group, a different which was not statistically significant; risk difference was 4.4% (95% CI -7.2% to 15.9%; P = .56). Differences between groups were analyzed with inverse probability of censoring weighs (IPCW) to account for patients without outcome data at 6 months due to withdrawn consent, death, and loss to follow-up. The unadjusted rate of recurrence was 10.3% in the aspirin group versus 9.1% in the placebo group. The rate of recurrence in the aspirin group was lower than anticipated, which affected the statistical power of the trial. The enrollment target of 157 patients was calculated based on estimated SDH recurrence rate of 10% in the placebo group and 28% in the aspirin group. The lower observed recurrence of 13.9% in the aspirin group led to limited statistical power to detect a difference between the groups.

Secondary outcomes included a trend towards more cardiovascular and cerebrovascular events in the placebo arm (14 versus 11 in the aspirin group), with major events occurring in 6 patients in the placebo group, compared with 3 in the aspirin treatment arm. These trends did not reach statistical significance.

Commentary: The strengths of this trial include the randomized, double-blind approach at multiple clinical sites. Recurrence of SDH requiring repeat surgical intervention is a clear, objective, and clinically relevant primary outcome measure. It should also be noted that this trial was not funded by industry. There was no statistically significant difference between the treatment and placebo groups, both before and after adjusting rates of recurrence based on IPCW. Of note, the authors did not report rates of recurrent, non-operative SDH in each group, a safety outcome that may be of interest. At first glance, continuation of aspirin might seem preferable for cSDH requiring burr hole evacuation in order to minimize risk of cardiovascular events. However, the trial design was based on a higher predicted rate of recurrence (28%), and this sample size may not be sufficient to detect a treatment effect.

Impact on Clinical Practice: In this study, perioperative continuation of aspirin in patients receiving burr hole evacuation of chronic SDH did not increase their risk of recurrent SDH at 6 months. This trial lacks appropriate statistical power to confidently guide a change in clinical practice but should promote further research on perioperative aspirin continuation in patients undergoing burr hole evacuation of chronic SDH.