Background: In patients with cancer-associated thrombosis (CAT), knowledge on risk factors for recurrent venous thromboembolism (VTE) and clinically relevant bleeding (CRB) during anticoagulant therapy is sparse.

Aims: To identify predictors of recurrent VTE and CRB during anticoagulant therapy.

Methods: Cumulative incidences and risk factors for recurrent VTE and CRB were evaluated in CAT patients from EDITH cohort using cumulative incidence functions (CIF) and competing risks analysis with cause-specific and Fine-Gray models, considering recurrent VTE and CRB as events of interest and death as competing risk.

Results: Among the 782 included patients, 84 (10.7%) patients developed recurrent VTE, 61 (7.8%) CRB, and 145 (18.5%) died during anticoagulation, at 18-month follow-up. The cumulative incidences of recurrent VTE, CRB and death at 18 months were 13.1% (95%CI, 10.5-15.9), 10.0% (95%CI, 7.7-12.7), 24.4% (95%CI, 20.8-28.0), respectively (Figure). Using a competing risk multivariable model, predictors for recurrent VTE were: metastasis (cause-specific hazard ratio (CHSR) 2.37 [95%CI, 1.49-3.77]; subdistribution hazard ratio (SHR) 1.90 [95%CI, 1.20-3.00]), male sex (CHSR 1.75 [95%CI, 1.09-2.83]; SHR 1.67 [95%CI, 1.03-2.69]), cancer surgery (CHSR 0.47 [95%CI, 0.27-0.81]; SHR 0.51 [95%CI, 0.30-0.86]), and BMI ?25 (CHSR 0.56 [95%CI, 0.35-0.90]; SHR 0.59 [95%CI, 0.37-0.92])(Table 1). Regarding the risk of CRB, the univariable analysis identified only chemotherapy (CHSR 0.55 [95%CI, 0.33-0.94]; SHR 0.58 [95%CI, 0.34-0.97.

Conclusions: During anticoagulation for CAT, metastasis, sex, cancer surgery, BMI and chemotherapy were predictive of recurrent VTE.