DOACs Associated With High Bleeding Rates, VTEs, ATEs in MPNs

The safety and efficacy of direct oral anticoagulants (DOACs) were retrospectively analyzed from medical records of patients with myeloproliferative neoplasms (MPNs) across multiple institutional databases. The data were shared at the 2021 Annual American Society of Hematology (ASH) Meeting.

“There are no clear guidelines regarding selection of anticoagulation (AC) in patients with MPNs. We’ve observed DOACs are increasingly used in the general population to treat arterial (ATE) and venous thromboembolism (VTE). Data on DOACs in MPNs is limited,” explained Chi-Joan How, MD, Brigham and Women’s Hospital, MA, and co-investigators.

Researchers of the multicenter, retrospective analysis sought to characterize real-world practice patterns and evaluate thrombosis and bleeding risks in patients with MPNs.

The study identified 133 patients with MPNs using ICD-9 and 10 codes across electronic medical records from Massachusetts General Brigham and Dana Farber Harvard Cancer Center institutional databases. ISTH criteria were used to calculate cumulative incidence functions of VTE, ATE, and major and clinically relevant non-major bleeding (CRNMB).

The results of the study identified the baseline characteristics of patients with MPNs, wherein 75 (56.4%) were prescribed with DOAC for VTE, 46 (34.6%) for AF, 7 (5.3%) for stroke, and 5 for other ATE (3.8%). The median age at DOAC initiation was 71, AF population was significantly older than patients with VTE (75 versus 59, p<0.001). 57% of patients (N=76) had a diagnosis of polycythemia vera (PV), with 89% (N=118) of patients expressed a JAK2 driver mutation.

Practice patterns of DOAC use were observed. The median duration of AC was 37 months for all patients with no difference (P=0.01) between patients treated with AF (42.3 months) and VTE (37 months). 21% of VTE-treated patients completed a finite course of AC with a median duration of 6 months.

“After a median follow-up of 37 months, we found 12 thrombotic (7 arterial, 3 venous, 2 TIPS occlusions) and 28 bleeding (6 major with 4 contributing to patient death, 2 CRNMB) events on DOAC. The estimated 1-year cumulative incidence of thrombosis and bleeding on DOAC was 5.5% and 12.3%, respectively,” continued Dr How and co-authors.

Notably, thrombosis and bleeding rates were not significantly different between patients treated for VF versus AF. Prior history of thrombosis and use of dabigatran or edoxaban were significantly associated with increased thrombosis in multivariate analysis (p=0.04).

“In our cohort, while our 5.5% thrombosis rate is similar to recurrent thrombosis rates reports in patients with MPN on DOACs and VKA, our 12.3% bleeding rate appears much higher. The higher-than-expected bleeding rate found in our study indicates the continued need for rigorous evaluations of DOACs in this population, with the gold standard being randomized controlled trials comparing DOAC with warfarin,” concluded Dr How, et al.—Alexa Stoia

How C, Story C, Ren S, et al. High Incidence of Bleeding Found with Direct Oral Anticoagulant Use in Myeloproliferative Neoplasm Patients. Presented at: Presented at: the 2021 ASH Annual Meeting; Dec. 11-14, 2021; Abstract 3632.