Financial Outcomes Among Medicaid Expansion Enrollees.

Importance: Enrollment in Medicaid expansion may improve financial outcomes for low-income adults, but this association has not been studied in the longer-term postenrollment period. Objective: To estimate the association of enrollment in Medicaid expansion with financial outcomes for enrollees as long as 7 years after enrollment. Design, Setting, and Participants: This longitudinal cohort study used an event study analysis to compare changes in credit outcomes after relative to before enrollment, controlling for changes in outcomes over time, differences between individuals who enroll at different times, and linear trends in outcomes prior to enrollment. Participants included first-time enrollees in the Healthy Michigan Plan (HMP), Michigan's Medicaid expansion plan, between April 1, 2014, and December 31, 2017. Enrollees were linked with their credit reports from a large national credit agency at 6-month intervals from 2013 to 2021, with outcomes obtained on the final business day of January and July of each calendar year. Data were analyzed from January 4, 2023, to December 9, 2025. Exposure: Enrollment in HMP. Main Outcomes and Measures: The event study analysis compared changes in 4 credit outcomes: medical debt in collections, nonmedical debt in collections, a subprime credit score (<600), and bankruptcy in the prior 2 years. Results: The study cohort included 575 283 enrollees (308 814 male [53.7%]; mean [SE] age, 42.1 [10.6] years). HMP enrollment was associated with large reductions in medical debt in collections (from -$101.9 [95% CI, -$127.6 to -$76.3] in postenrollment quarter 8 to -$983.0 [95% CI, -$1090.8 to -$875.1] in postenrollment quarter 29) and rates of subprime credit scores (from -0.038 [95% CI, -0.041 to -0.035] in postenrollment quarter 8 to -0.234 [95% CI, -0.247 to -0.221] in postenrollment quarter 29), with the magnitude of association increasing over time. No associations were observed between HMP enrollment and nonmedical debt in collections or bankruptcy. Conclusions and Relevance: In this cohort study of HMP enrollees, Medicaid expansion enrollment was associated with reductions in medical debt in collections and rates of subprime credit scores as long as 7 years after enrollment. These results suggest enrollment in Medicaid expansion was associated with excellent protection from out-of-pocket costs of medical care and overall improved financial stability, which in turn may be associated with improvements in enrollees' health and well-being.