Abstract 18707: Do Patients with Heart Failure and Atrial Fibrillation Adhere to Warfarin After Hospital Discharge? Findings from the Get With The Guidelines-Heart Failure Registry and Medicare Linked Database
Background: Prescribing warfarin at hospital discharge in patients with heart failure (HF) and atrial fibrillation (AF) without contraindications is recommended. Post-discharge adherence and long-term persistence to warfarin therapy among patients with HF and AF has not been fully described.
Methods: We identified patients with HF and AF who were ≥65 years, without contraindications to warfarin therapy, and discharged home from hospitals in the GWTG-HF Registry from 1/2006-12/2009. We used linked Medicare prescription drug event data to measure adherence. Main outcome measures were prescription at discharge, outpatient prescription claim within 90 days, discontinuation, and adherence measured with the medication possession ratio. We used the cumulative incidence function to estimate rates of initiation and discontinuation.
Results: Among 2691 eligible patients, 1856 (69.0%) were prescribed warfarin at discharge (Table). Within 90 days, 84.5% of eligible patients who had a discharge prescription filled a prescription for the therapy, compared with 12.3% of eligible patients without a discharge prescription (P<0.001). The median medication possession ratio over 1 year of follow-up was significantly higher among patients who were prescribed warfarin therapy at discharge (0.78 vs. 0.63) than among those not prescribed therapy (P<0.001). Among 1,631 patients who filled a prescription within 90 days of discharge, 7.1% discontinued therapy within 1 year.
Conclusions: Approximately one-third of eligible patients with HF/AF and no reported contraindication to anticoagulation were not prescribed warfarin therapy at discharge from an HF hospitalization. Eligible patients without a discharge prescription seldom initiated therapy as outpatients. Most patients who were prescribed warfarin at discharge filled the prescription within 90 days and remained on therapy; yet even among these patients, opportunities to improve adherence remain. .
- © 2012 by American Heart Association, Inc.