Quality of care for atrial fibrillation among patients hospitalized for heart failure

Abstract

Objectives: This study sought to examine quality of care and warfarin use at discharge in patients with atrial fibrillation (AF) and heart failure (HF).

Background: Atrial fibrillation is common in HF, and national guidelines recommend discharge on warfarin for stroke prophylaxis. However, the frequency and factors associated with the guideline adherence are poorly described.

Methods: We analyzed 72,534 HF admissions from January 2005 through March 2008 at 255 hospitals participating in the American Heart Association's Get With The Guidelines HF program. Multivariable logistic regression was used to identify independent factors associated with warfarin use at discharge.

Results: In this HF population, 20.5% (n=14,901) had AF on admission, whereas another 13.7% (n=9,918) had a prior history of AF but were in a regular rhythm at admission. Contraindications to warfarin therapy were documented in 9.2%. Among eligible HF patients without contraindications, the median prevalence of warfarin therapy at discharge was 64.9% (interquartile range 55.5 to 73.4) and did not improve during the 3.5 years of study. After adjustment, major factors associated with no warfarin use at discharge included increasing age, nonwhite race, anemia, and treatment in the south. Warfarin use also varied inversely with CHADS2 (congestive heart failure, hypertension, age>75, diabetes, and prior stroke or transient ischemic attack) risk (70.9% to 59.5% for CHADS2 score 1 to 6, p<0.0001).

Conclusions: Guideline-recommended warfarin use in patients with AF and HF is less than optimal, has not improved over time, and varies significantly according to age, race, risk profile, region, and hospital site.