Outcomes and cost among Medicare beneficiaries hospitalized for heart failure assigned to accountable care organizations

Abstract

Little is known about the impact of accountable care organizations (ACO) on hospitalized heart failure (HF) patients, a high-cost and high-risk population.

Objective: We linked Medicare fee-for-service claims from 2013 to 2015 with data from American Heart Association Get With The Guidelines-HF registry to compare HF care, post-discharge outcomes, and total annual Medicare spending by ACO status at discharge.

Methods: Using adjusted Cox models and accounting for competing risks of death, we compared all-cause mortality and readmission at 1 year by ACO status with reporting of hazard ratios (HR) and 99% confidence intervals (CI).

Results: The study included 45,259 HF patients from 300 hospitals, with 21.1% assigned to an ACO. Patient characteristics were similar between the two groups with a few exceptions. The ACO patients lived in geographic areas with higher median income ($54400 [IQR $48600-65900] vs $52300 [$45900-61200], P < .0001). Compliance with four HF-specific quality measures was modestly higher in the ACO group (80% vs 76%, P < .0001). In adjusted analysis, ACO status was associated with similar all-cause readmission (HR: 1.03; 99% CI: 0.99, 1.07) but lower risk of 1-year mortality (HR: 0.85; 99% CI: 0.85, 0.90) compared with non-ACO status. Median Medicare spending in the calendar year of hospitalization was similar (ACO $42,737 [IQR $23,011-72,667] vs non-ACO $42,586 [$22,896-72,518], P = 0.06).

Conclusions: Among Medicare patients hospitalized for HF, participation in an ACO was associated with similar rates of all-cause readmission and no associated cost reductions compared with non-ACO status. There was a lower risk of 1-year mortality associated with ACO participation, which warrants further evaluation.