Direct oral anticoagulants in patients with nonvalvular atrial fibrillation and extreme body weight

Abstract

Bodega et al.'s recent report on the efficacy and safety of direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation and extreme body weight reinforces recent therapeutics advances in anticoagulation in these patient cohorts.1 Their finding of lack of difference in recurrent thromboembolic events between two weight categories (extreme and normal) in patients with atrial fibrillation stabilized on a DOAC-based anticoagulation strategy is consistent with the most recent guideline updates in these patient cohorts (body mass index [BMI] >40 kg/m2 or weight > 120 kg). Clinical decisions regarding the commencement of anticoagulation amongst certain patients' groups have continued to be subjects of ongoing therapeutic debate. One of these is the utility and safety of DOACS (for all indications) amongst patients' cohorts with BMI >40 kg/m2 or weight > 120 kg. These are vulnerable therapeutic groups for which ‘actionable’ trial data (regarding both efficacy and safety) have been lacking (until recently). DOACs as a class have variable pharmacokinetics (PK) accounting for the well-reported differences in PK parameters amongst its various analogues.2 Conversely, their pharmacodynamic (PD) outcome data thus far have shown insignificant differences between the various analogues.3, 4 Currently, available PD data with regard to DOACs and from which prescriptive guideline-directed recommendations for their use were made have principally accrued from clinical trials of which patients with outlying BMI ranges were either limited (in number) or excluded3, 4 Table 1. Their use in patients with BMI >40 kg/m2, therefore, raises understandable concerns regarding both clinical effectiveness and safety.