County-Level Variation in Triple Guideline-Directed Medical Therapy in Heart Failure With Reduced Ejection Fraction.

Background: Current guidelines recommend simultaneous initiation of multidrug guideline-directed medical therapy classes for heart failure with reduced ejection fraction. Objectives: The purpose of this study was to evaluate county-level variation in use of triple guideline-directed medical therapy, defined as simultaneous prescription fills for beta-blockers, renin-angiotensin system inhibitors or angiotensin receptor neprilysin inhibitors, and mineralocorticoid receptor antagonists, in heart failure with reduced ejection fraction. Methods: We conducted a cohort study using Medicare Fee-for-Service claims data (parts A, B, and D between 2013 and 2019). Features of counties including area-level indicators of poverty, employment, and educational attainment and aggregated patient-level sociodemographic and medical history variables were compared by quintiles of triple therapy use. A multilevel logistic regression model was constructed to estimate the contextual effect of clustering by counties, which was expressed as a median OR. Results: 304,857 patients from 2,600 counties (83% of all U.S. counties) were included. The median for triple therapy use was 14.3% (IQR: 10.3%-18.8%) across included counties with a wide variation (range: 0%-54.5%). Compared to counties in the highest use quintile, counties in lowest triple therapy use quintile had worse area-level indicators of socioeconomic status (% unemployment 6.8% vs 6.2%). Counties in lowest quintile had higher proportion of Black patients (13.3% vs 5.7% in highest quintile) and patients with low-income subsidy (29.3% vs 25.8% in highest quintile). The median OR was 1.30 (95% CI: 1.28-1.33). Conclusions: We observed variation in triple therapy use across counties in the United States with suboptimal local use patterns correlating with indicators of socioeconomic disadvantage.