Antithrombotic therapy and risk of intracranial hemorrhage in patients with cerebral cavernous malformations: a multicenter propensity-matched cohort study

Background: The safety of antithrombotic therapy in patients with cerebral cavernous malformations (CCMs) without prior intracranial hemorrhage (ICH) remains uncertain. Methods: We conducted a retrospective, multicenter, propensity score-matched cohort study using the TriNetX Analytics Platform. Adult patients with CCMs and no prior ICH were included. Patients receiving antithrombotic therapy (antiplatelet or anticoagulant) were compared with those receiving no antithrombotic therapy. The primary outcome was ICH; secondary outcomes included seizures, inpatient readmission, and emergency department (ED) visits. Subgroup analyses evaluated outcomes by antithrombotic class. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Results: Among 8989 eligible patients, 1540 in each group were matched. ICH occurred more frequently in the antithrombotic group (6.3%) than in the no-therapy group (3.9%) (HR 1.77, 95% CI 1.28–2.44; log-rank p < 0.001). Seizures (18.6% vs 10.9%; HR 1.84, 95% CI 1.52–2.23), inpatient readmission (57.3% vs 31.8%; HR 2.38, 95% CI 2.13–2.65), and ED visits (39.3% vs 28.4%; HR 1.70, 95% CI 1.50–1.92) were more common. In subgroup analyses, anticoagulant use increased ICH risk (6.8% vs 3.6%; HR 2.14, 95% CI 1.31–3.51; p = 0.002), whereas antiplatelet use did not (5.2% vs 4.3%; HR 1.24, 95% CI 0.73–2.08; p = 0.424). Conclusions: In CCM patients without prior ICH, antithrombotic therapy was associated with increased risk of ICH and other adverse outcomes, primarily driven by anticoagulants.