DOAC in renal impairment – Cardiology MCQ – Answer
Which of the following direct oral anticoagulants (DOACs) is most suitable in a patient with atrial fibrillation and renal dysfunction – Correct answer: b) Apixaban
Elimination of apixaban is mainly hepatic and hence accumulation in renal dysfunction is minimal. Hence it is the best suited DOAC in renal impairment. A recent retrospective cohort study of end-stage kidney disease (ESKD) had 2351 patients on apixaban and 23,172 patients on warfarin . There was no significant difference in the risks of stroke or systemic embolism between apixaban and warfarin (P=0.29). At the same time bleeding risk was significantly lower with apixaban (P<0.001). The standard apixaban dose of 5 mg twice daily was associated with lower mortality and stroke/systemic embolism. It may noted that apixaban dose has to be reduced to 2.5 mg twice daily if two of the following three conditions are there: (1) Serum creatinine 1.5 mg/dL or more (2) Weight below 60 Kg or below (3) Age 80 years or more.
Dabigatran, Rivaroxaban and Betrixaban have significant renal excretion and safety is reduced in the presence of renal dysfunction. This is more so when drugs which inhibit cytochrome P450 and transporter permeability glycoprotein (P-gp) like amiodarone  are used as co-prescription. Many patients with non valvular atrial fibrillation (NVAF) who receive DOAC from stroke prevention also need amiodarone for AF.