Federally Qualified Health Centers and Performance of Medicare Accountable Care Organizations.

Importance: Federally qualified health centers (FQHCs) have increasingly participated in the Medicare Shared Savings Program (MSSP) accountable care organizations (ACOs), one of the most widespread value-based programs. Although FQHCs may strengthen ACOs' ability to provide affordable care to diverse Medicare beneficiaries, evidence on ACOs' performance by FQHC participation is limited. Objectives: To compare beneficiary characteristics, utilization, expenditure, and quality between ACOs with and without FQHC participation and assess changes in ACO performance after including first FQHCs. Design, Setting, and Participants: Using MSSP public use files, this cross-sectional study compared performance of ACOs that always had FQHC participation with ACOs that never had FQHC participation from January 1, 2016, to December 31, 2022, supplemented with staggered difference-in-differences analyses of ACOs' first-time inclusion of FQHCs on performance measures. Data analysis was performed from December 1, 2023, to February 29, 2024. Exposure: Participation of FQHCs in the MSSP. Main Outcomes and Measures: Measures of ACO-assigned beneficiaries, utilization, expenditure, and quality per ACO-year. Results: Among 752 ACOs in the descriptive analysis, 140 ACOs always had at least 1 FQHC participant, whereas 612 ACOs never had FQHC participants. Compared with ACOs that never had FQHC participation, those that always had FQHC participation provided care to more socioeconomically disadvantaged beneficiaries (mean [SD] with dual eligibility, 2035.8 [2110.6] vs 1040.9 [1084.2] person-years; with disability, 3341.1 [3474.9] vs 1705.1 [1664.9] person-years; in racial and ethnic minoritized groups, 3690.6 [4118.4] vs 2515.1 [2762.9] person-years), with fewer primary care visits (mean [SD], 9956.6 [1926.3] vs 10 858.8 [2383.4] per 1000 person-years), more emergency department visits (mean [SD], 771.6 [190.9] vs 657.2 [160.0] per 1000 person-years), and lower levels of several quality measures. In the difference-in-differences analysis, 43 ACOs included FQHCs for the first time. Including first FQHCs was associated with increases of 872.9 dual-eligible (95% CI, 345.9-1399.8), 1137.6 disability (95% CI, 390.1-1885.1), and 1350.8 racial and ethnic minority (95% CI, 447.4-2254.1) person-years, with increases in rates of influenza immunization (5.9 percentage points [pp]; 95% CI, 1.4-10.4 pp), tobacco screening and cessation intervention (11.8 pp; 95% CI, 3.7-20.0 pp), and depression screening and follow-up (8.9 pp; 95% CI, 0.5-17.4 pp). No associations were observed between FQHC inclusion and utilization or expenditure. Conclusions and Relevance: In this repeated cross-sectional study, MSSP ACOs with FQHC participation served more socioeconomically disadvantaged Medicare beneficiaries than those without FQHC participation. The inclusion of first FQHCs was associated with increased rates of several preventive services without increasing costs. Participation of safety net practices appeared to improve access to ACOs among beneficiaries from underserved communities.