Quality of life after switching from well-controlled vitamin K antagonist to direct oral anticoagulant: Little to GAInN.

Background: Direct oral anticoagulants (DOAC) and vitamin K antagonists (VKA) prevent thromboembolism in atrial fibrillation (AF). DOAC have a fixed dosing regimen and obviate INR monitoring. Therefore, DOAC presumably affect quality of life (QoL) less than VKA. However, some VKA users appreciate the monitoring. A high time in the therapeutic range (TTR) leads to a lower impact on QoL. We assessed the influence of switching from well-controlled VKA to a DOAC on QoL.

Methods: In the GAInN study, 241 patients with AF, a TTR ≥ 70%, and neither bleeding nor thrombosis while on VKA were randomised to switching to DOAC (n = 121) or continuing VKA (n = 120). Health-related (SF-36) and anticoagulation-related QoL (PACT-Q) was assessed at baseline and after six and twelve months of follow-up.

Results And Conclusion: SF-36 development did not differ between groups. After one year, average PACT-Q Convenience improvement was 2.5 (0.3-4.7) higher on DOAC. DOAC users were 6percentage points (95%CI -4-16) more likely to improve >5 points on Convenience; 22 pp. (95%CI 1-43) in patients who scored <95/100 at baseline. The probability to meaningfully improve on PACT-Q Satisfaction was 12 pp. (95%CI 0-25) higher on DOAC. However, 5 (4.1%) and 4 (3.3%) DOAC users resumed VKA because of side-effects and patient preference. Switching from well-controlled VKA to DOAC for AF leads to a higher probability of improved PACT-Q convenience and satisfaction, but also to a higher risk of side-effects. Arguably only patients who are not satisfied with VKA should switch, because they have more to gain by switching.