Comparison of Health Care Utilization by Medicare Advantage and Traditional Medicare Beneficiaries With Complex Care Needs.

Importance: Medicare beneficiaries with co-occurring chronic conditions and complex care needs experience high rates of acute care utilization and poor outcomes. These patterns are well described among traditional Medicare (TM) beneficiaries, but less is known about outcomes among Medicare Advantage (MA) beneficiaries. Compared with TM, MA plans have additional levers to potentially address beneficiary needs, such as network design, care management, supplemental benefits, and value-based contracting. Objective: To compare health care utilization for MA and TM beneficiaries with complex care needs. Design, Setting, and Participants: This cross-sectional study analyzed beneficiaries enrolled in MA and TM using claims data from a large, national MA insurer and a random 5% sample of TM beneficiaries. Beneficiaries were segmented into the following cohorts: frail elderly, major complex chronic, and minor complex chronic. Regression models estimated the association between MA enrollment and health care utilization in 2018, using inverse probability of treatment weighting to balance the MA and TM cohorts on observable characteristics. The study period was January 1, 2017, through December 31, 2018. All analyses were conducted from December 2020 to August 2022. Exposures: Enrollment in MA vs TM. Main Outcomes and Measures: Hospital stays (inpatient admissions and observation stays), emergency department (ED) visits, and 30-day readmissions. Results: Among a study population of 1 844 326 Medicare beneficiaries (mean [SD] age, 75.6 [7.1] years; 1 021 479 [55.4%] women; 1 524 458 [82.7%] White; 223 377 [12.1%] with Medicare-Medicaid dual eligibility), 1 177 896 (63.9%) were enrolled in MA and 666 430 (36.1%) in TM. Beneficiary distribution across cohorts was as follows: frail elderly, 116 047 with MA (10.0% of the MA sample) and 104 036 with TM (15.6% of the TM sample); major complex chronic, 320 954 (27.2%) and 158 811 (23.8%), respectively; and minor complex chronic, 740 895 (62.9%) and 403 583 (60.6%), respectively. Beneficiaries enrolled in MA had lower rates of hospital stays, ED visits, and 30-day readmissions. The largest relative differences were observed for hospital stays, which ranged from -9.3% (95% CI, -10.9% to -7.7%) for the frail elderly cohort to -11.9% (95% CI, -13.2% to -10.7%) for the major complex chronic cohort. Conclusions and Relevance: In this cross-sectional study of Medicare beneficiaries with complex care needs, those enrolled in MA had lower rates of hospital stays, ED visits, and 30-day readmissions than similar beneficiaries enrolled in TM, suggesting that managed care activities in MA may influence the nature and quality of care provided to these beneficiaries.