Patients with Cushing's syndrome suffer from provoked venous thromboembolism and are anticoagulated in various patterns.

Objective: Cushing's syndrome (CS) is associated with an 18-fold greater risk of venous thromboembolism (VTE). We aimed to identify factors which provoke VTE among patients with CS and VTE and to describe the anticoagulant regimen used in these cases.

Methods: In this retrospective observational study, patients included in the European Registry on CS (ERCUSYN) in Krakow center, Poland, were followed for the occurrence of VTE and anticoagulant treatment. We identified factors provoking VTE according to the International Society of Thrombosis and Hemostasis (ISTH), along with factors included in the Padua score and CS-VTE score.

Results: Of the 128 patients followed for a median of 4.3 years, there were nine patients who experienced ten VTE episodes (prevalence of 7.8% and incidence of 13.4 per 1000 patient-years). All VTEs were classified as provoked according to the ISTH guidance, predominantly due to the transient major and minor (50% and 20%, respectively) factors, while they were less commonly due to persistent (30%) factors. In 2/9 patients, we could not identify any risk factor for VTE according to the Padua score, while in 2/6 patients according to the CS-VTE score. Patients were mostly anticoagulated with vitamin K antagonists (4/8 patients), followed by direct oral anticoagulants (3/8) and low-molecular-weight heparin (1/8). The median duration of anticoagulation was 2.75 years and exceeded beyond the primary treatment in 28% of episodes provoked by transient factors.

Conclusion: Further, multicenter studies are required to create a validated thrombotic risk score and guidelines regarding VTE treatment in CS patients.