Medicare Advantage (MA) plans have grown rapidly in recent years, potentially causing a “spillover” effect that impacts the cost efficiency and quality of care provided to individuals enrolled in fee-for-service (FFS) Medicare. This study uses national Medicare data from 2010-2017 to determine if the growth in MA plans influenced spending and utilization for Medicare FFS beneficiaries with comorbid conditions.

This study found that growth in MA plans was associated with decreased spending and emergency department visits among Medicare FFS beneficiaries with six or more chronic conditions, but did not affect readmission rates. MA plans can include supplemental benefits into their benefit packages to support beneficiary social needs, which may improve the cost efficiency of care. These results suggest that growth in MA plans may drive improvements in clinical practice for health systems treating patients with complex needs, and policymakers should consider incorporating innovations from MA into FFS Medicare.