Re: Effectiveness and safety of reduced dose non-vitamin K antagonist oral anticoagulants and warfarin in patients with atrial fibrillation: propensity weighted nationwide cohort study
Nielsen et al. found that rivaroxaban prescribed in the reduced dose was associated with an increased risk of mortality in the main analysis. In all additional and sensitivity analyses, both rivaroxaban and apixaban in the reduced dose exhibited associations favouring warfarin in relation to an increase in risk of mortality. In order to explain this finding the authors argue that there might be some residual confounding. An alternative explanation to be considered is that in patients receiving the reduced dose of a NOAC in this population, treatment with well-controlled warfarin might have been a better option.
Competing interests: No competing interests