Venous thromboembolism recurrence among one-and-done direct oral anticoagulant users: a retrospective longitudinal study.

Background: Direct oral anticoagulants (DOACs) are the American Society of Hematology guideline-recommended treatment for venous thromboembolism (VTE) in the United States (US).

Aim: To compare risk of VTE recurrence between patients who, following the first fill, discontinued ("one-and-done") versus those who continued ("continuers") DOACs.

Method: Open source US insurance claims data (04/1/2017 to 10/31/2020) were used to select adult patients with VTE initiated on DOACs (index date). Patients with only one DOAC claim during the 45-day landmark period (starting on the index date) were classified as one-and-done and the remaining as continuers. Inverse probability of treatment weighting was used to reweight baseline characteristics between cohorts. VTE recurrence based on the first post-index deep vein thrombosis or pulmonary embolism event was compared using weighted Kaplan-Meier and Cox proportional hazard models from landmark period end to clinical activity or data end.

Results: 27% of patients initiating DOACs were classified as one-and-done. After weighting, 117,186 and 116,587 patients were included in the one-and-done and continuer cohorts, respectively (mean age 60 years; 53% female; mean follow-up 15 months). After 12 months of follow-up, the probability of VTE recurrence was 3.99% and 3.36% in the one-and-done and continuer cohorts; the risk of recurrence was 19% higher in the one-and-done cohort (hazard ratio [95% confidence interval] = 1.19 [1.13, 1.25]).

Conclusion: Substantial proportion of patients discontinued DOAC therapy after the first fill, which was associated with significantly higher risk of VTE recurrence. Early access to DOACs should be encouraged to reduce the risk of VTE recurrence.