Risks associated with discontinuation of oral anticoagulation in newly diagnosed patients with atrial fibrillation: Results from the GARFIELD-AF Registry

Abstract

Background: Oral anticoagulation (OAC) in atrial fibrillation (AF) reduces the risk of stroke/systemic embolism (SE). The impact of OAC discontinuation is less well documented.

Objective: Investigate outcomes of patients prospectively enrolled in the Global Anticoagulant Registry in the Field-Atrial Fibrillation study who discontinued OAC.

Methods: Oral anticoagulation discontinuation was defined as cessation of treatment for ≥7 consecutive days. Adjusted outcome risks were assessed in 23 882 patients with 511 days of median follow-up after discontinuation.

Results: Patients who discontinued (n = 3114, 13.0%) had a higher risk (hazard ratio [95% CI]) of all-cause death (1.62 [1.25-2.09]), stroke/systemic embolism (SE) (2.21 [1.42-3.44]) and myocardial infarction (MI) (1.85 [1.09-3.13]) than patients who did not, whether OAC was restarted or not. This higher risk of outcomes after discontinuation was similar for patients treated with vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) (p for interactions range = 0.145-0.778). Bleeding history (1.43 [1.14-1.80]), paroxysmal vs. persistent AF (1.15 [1.02-1.29]), emergency room care setting vs. office (1.37 [1.18-1.59]), major, clinically relevant nonmajor, and minor bleeding (10.02 [7.19-13.98], 2.70 [2.24-3.25] and 1.90 [1.61-2.23]), stroke/SE (4.09 [2.55-6.56]), MI (2.74 [1.69-4.43]), and left atrial appendage procedures (4.99 [1.82-13.70]) were predictors of discontinuation. Age (0.84 [0.81-0.88], per 10-year increase), history of stroke/transient ischemic attack (0.81 [0.71-0.93]), diabetes (0.88 [0.80-0.97]), weeks from AF onset to treatment (0.96 [0.93-0.99] per week), and permanent vs. persistent AF (0.73 [0.63-0.86]) were predictors of lower discontinuation rates.

Conclusions: In GARFIELD-AF, the rate of discontinuation was 13.0%. Discontinuation for ≥7 consecutive days was associated with significantly higher all-cause mortality, stroke/SE, and MI risk. Caution should be exerted when considering any OAC discontinuation beyond 7 days.

Trial registration: ClinicalTrials.gov NCT01090362.

Keywords: anticoagulation; antiplatelet; atrial fibrillation; discontinuation; marginal structure models; outcomes.