Comparison of Treatment Persistence with Dabigatran or Rivaroxaban versus Vitamin K Antagonist Oral Anticoagulants in Atrial Fibrillation Patients: A Competing Risk Analysis in the French National Health Care Databases.

BACKGROUND

Direct oral anticoagulants (DOACs) have been proposed as a more convenient alternative to vitamin K antagonists (VKAs), which are commonly associated with poor treatment persistence in non-valvular atrial fibrillation (nv-AF).

METHODS

Using data from the French national health care databases (Régime Général, 50 million beneficiaries), a cohort study was conducted to compare the 1-year non-persistence rates in nv-AF patients initiating dabigatran (N=11,141) or rivaroxaban (N=11,126) versus VKA (N=11,998). Treatment discontinuation was defined as a switch between oral anticoagulant (OAC) classes or a 60-day gap with no medication coverage, with the additional criterion of no reimbursement for international normalized ratio monitoring during this gap for VKA patients. Considering death as a competing risk, differences between 1-year discontinuation rates were used to compare each DOAC versus VKA. The 95% confidence intervals (CIs) were estimated via bootstrapping. Baseline patient characteristics were adjusted using inverse probability of treatment weighting. Subgroup analyses considered DOAC dose at initiation, age, risk of stroke, and bleeding.

RESULTS

Adjusted 1-year discontinuation rates were higher for dabigatran than for VKA new users (36.8% vs 30.2%; difference: 6.6% [95% CI, 5.5-7.6]) and for rivaroxaban versus VKA new users (33.4% vs 30.4%; 3.0% [1.9-4.1]). Similar differences were found in all subgroup analyses, except in dabigatran and rivaroxaban patients <75 years (dabigatran vs VKA: 0.3% [-1.4 to 1.8]; rivaroxaban vs VKA: -2.6% [-4.3 to -0.9]) and dabigatran 150 mg new users (-1.1% [-3.1 to 0.7]). Consistent results were obtained when considering both switches between OAC classes and death as competing risks of treatment discontinuation.

CONCLUSION

Results from this nationwide cohort study showed high non-persistence levels with all OACs and suggest that persistence with both dabigatran and rivaroxaban therapy is not better than persistence with VKA therapy. Hospitalizations for bleeding among non-persistent patients were unlikely to explain these high non-persistence rates.