Impact of Medicaid Continuous Glucose Monitor Expansion on Uptake, Glycemic Outcomes, and Engagement Among Adults With Type 2 Diabetes in a Federally Qualified Health Center.

Abstract

Continuous glucose monitors (CGMs) improve outcomes for adults with type 2 diabetes yet use remains low in underserved populations. California's 2022 Medicaid coverage expansion aimed to reduce access barriers, but its impact in safety-net settings is not well understood. We conducted a retrospective cohort study of adults with type 2 diabetes receiving care at a federally qualified health center from January 2022 to June 2023. Electronic health records assessed CGM uptake and glycemic outcomes. Telephone surveys (November 2023-February 2025) evaluated patient perceptions and engagement. Time-to-event models estimated the association between CGM initiation and achieving a ≥1% hemoglobin A1c (HbA1c) reduction. Open-ended responses were analyzed thematically. Among 256 adults, 126 (49%) initiated CGM use, with uptake increasing after Medicaid expansion. In the analytic sample (n = 230), CGM new users were associated with a higher but not statistically significant hazard of achieving a ≥1% HbA1c reduction (adjusted HR = 1.31; 95% CI: 0.87-1.97). Among survey respondents (n = 82), commonly cited benefits included improved glucose management and convenience, while engagement varied across behaviors. Medicaid coverage expansion increased CGM use in a safety-net population. High acceptability alongside variable engagement highlights the need for targeted implementation strategies to translate expanded access into equitable clinical benefit.