OBJECTIVES: Two-sided risk Medicare Advantage (MA) arrangements (at-risk MA) outperform Medicare fee-for-service (FFS) arrangements in quality and efficiency. The influence of social determinants of health (SDOH) remains unclear. Using the Social Vulnerability Index (SVI) as a proxy for SDOH, we compared outcomes for beneficiaries with varying levels of social vulnerability across at-risk MA, FFS MA, and FFS Medicare (traditional Medicare [TM]) arrangements.
STUDY DESIGN: Retrospective cohort study.
METHODS: We analyzed TM claims from 2019 and MA encounter data for 1,703,060 beneficiaries attributed to 16 physician groups in at-risk MA. Two models were estimated: (1) adjusting for SVI and (2) modeling SVI as interactions. We used multivariable logistic regression to analyze outcomes.
RESULTS: At-risk MA outperformed FFS in all 8 outcomes regardless of SVI. We found that at-risk MA outperformed FFS TM in 5 of 8 outcomes for beneficiaries with higher social vulnerabilities. Compared with TM, at-risk MA beneficiaries had 13.5% to 16.6% fewer acute admissions, 2.0% to 3.6% fewer emergency department (ED) visits, 10.9% to 14.4% fewer inpatient admissions through the ED, less than 1% fewer office visits, and 23.4% to 30.0% fewer instances of high-risk medication use, with the greatest differences observed in beneficiaries living in high SVI areas. At-risk MA also exhibited better quality metrics than FFS MA, but to a lesser extent than FFS TM.
CONCLUSIONS: This observational study found that beneficiaries in at-risk MA received higher-quality, more efficient care-especially in groups with elevated social vulnerability-suggesting that these populations benefit from value-based care (VBC) arrangements. Additional research is required to identify the specific VBC components driving quality and efficiency differences.