OBJECTIVES: For decades the US Medicare system has provided two options: public traditional fee-for-service (FFS) and private managed Medicare Advantage (MA); however, little is known about who is selecting FFS versus MA and differences in outcomes before and after enrollment. This study provides a first look at demographic, clinical, and social risk characteristics of individuals who select MA versus FFS while covered by commercial insurance prior to turning age 65 and compares healthcare outcomes before and after enrolling.

METHODS: Beneficiaries were continuously enrolled in a commercial plan for one-year prior to joining Medicare (baseline) within 3-months of reaching age 65 (index date) 2015-2018 and in MA or FFS one-year post-index. Patient characteristics were evaluated during baseline; healthcare resource utilization Per-100-Members-Per-Year (P100MPY), costs, and quality outcomes were compared during baseline and the one-year after enrollment.

RESULTS: Of 205,557 beneficiaries, 87.6% enrolled in FFS; 12.4% MA. FFS had fewer males (39.7% vs 41.5%) and more Whites (95.6% vs 90.6%). More selecting MA were in a commercial Healthcare Maintenance Organization (HMO) (45.8% vs. 27.8%) while more selecting FFS were in a Preferred Provider Organization (PPO) (56.6% vs 43.4%). MA enrollees had higher social risk (e.g., low income, high-school education, low English proficiency). MA and FFS enrollees had similar prevalence of chronic conditions but those selecting FFS had 26.5% higher costs during baseline and 27.1% higher costs post-index. Beneficiaries selecting FFS had 15.2% higher hospitalization rates during baseline (6.08 vs. 5.28), increasing to 54.4% higher hospitalization rates after joining Medicare (9.88 vs 6.40).

CONCLUSIONS: This study is the first to profile who is selecting FFS versus MA and compare outcomes under commercial coverage to outcomes after enrolling in Medicare. With the rapid growth of Medicare and move toward value-based care, it is essential stakeholders understand who is enrolling in MA versus FFS and expected differences in outcomes.