Abstract 10643: Anticoagulation Prescriptions for Patients With Acute Precipitants of Atrial Fibrillation in the VITAL-AF Study

Introduction: Many patients with incident atrial fibrillation (AF) are diagnosed in the setting of a potentially transient precipitant. Despite substantial rates of AF recurrence and stroke in this population, prior registries and survey data suggest lower usage of oral anticoagulants (OAC). Here, we examined use of OAC on the basis of precipitated versus non-precipitated AF among patients enrolled in the VITAL-AF trial. Methods: VITAL-AF (clinicaltrials.gov NCT03515057) was a cluster randomized trial of 16 primary care practices evaluating point-of-care AF screening using single-lead ECGs among individuals aged ≥ 65 years (n=30,715). The primary outcome of newly diagnosed AF at one year occurred in 503 patients. For each incident AF event, we performed manual chart review to classify if diagnosis occurred in the setting of an acute precipitant, if the episode was transient, and if OAC was initiated. AF was considered transient if there was documented return to sinus rhythm within three months of initial diagnosis. OAC initiation required both evidence of a new prescription and corresponding provider documentation Results: Of the 503 cases of incident AF diagnosed during the VITAL-AF study period, 125 (24.9%) occurred in the setting of an acute precipitant. The mean age of patients with newly diagnosed AF was 78.3 ± 9.0 years, 46% were female, 11% were non-white, and the mean CHA 2 DS 2 -VASc score was 4.2 ± 1.6, which were similar between those with and without a precipitant. Patients with acute precipitants of AF were more likely to have transient episodes (94% vs 76%, p=0.001) and less likely to be started on OAC (60% vs 82%, p<0.001) than patients without a precipitant. In a multivariable model adjusted for age, race, gender, CHA 2 DS 2 -VASc score, study arm, and screening status, AF occurring in the context of a precipitant was associated with significantly decreased odds of OAC initiation (odds ratio [OR] 0.32, 95% CI [0.20, 0.52]). Conclusions: Patients diagnosed with precipitated AF are more likely to have transient episodes with return to sinus rhythm within three months of diagnosis and less likely to be started on OAC compared to patients without a precipitant. Future analyses examining the effectiveness of OAC among patients with precipitated AF are warranted.