The Impact of Medicare Coverage on the Treatment of Opioid Use Disorders

• In Event: Responding to High-Need Populations: Medicare Policy in Action

Abstract

On January 1, 2020, Medicare Part B began covering opioid use disorder (OUD) treatments, including medications and outpatient services, under the implementation of the Substance Use-Disorder Prevention that Promotes Opioid Recovery and Treatment for Patients and Communities (SUPPORT) Act of 2018. However, little is known about how this coverage expansion affects OUD treatment uptake among Medicare beneficiaries. This study examines whether the passage of the SUPPORT Act influenced the likelihood of OUD treatment and treatment completion for OUD patients in Medicare compared to other substance use disorder (SUD) patients in Medicare. 

We applied a difference-in-differences and event study methodology to examine the causal impact of the SUPPORT Act among Medicare beneficiaries with OUD. We acquired datasets from 2015 to 2022 Treatment Episodes Datasets – Discharge from the Substance Abuse and Mental Health Services Administration. Outcomes in this study include intensive, non-intensive outpatient services, inpatient services, and treatment completion rates. Intensive outpatient means treatment lasting two or more hours per day for three or more days per week (more than six hours per week). Non-intensive outpatient treatment services include individual, family, and/or group services and pharmacological therapies that last less than six hours per week. All analyses are clustered at the state level and adjusted by covariates. We identified 14,471 observations of Medicare beneficiaries with OUD (treatment group), 9,329 observations of Medicare beneficiaries with other SUD (comparison group).

We found that after Medicare’s coverage in 2020, Medicare beneficiaries with OUD were 14.3 percentage points (pp) more likely (p<0.01) to receive non-intensive outpatient services relative to the other SUD group. However, Medicare beneficiaries are less likely to receive intensive services and inpatient services, showing a 5.78 pp reduction and a 6.46 pp reduction (p<0.05), respectively. Additional analyses revealed that Medicare beneficiaries with OUD were less likely to complete treatment (-12.8 pp, p<0.001), driven by reductions in intensive and inpatient OUD services. The results of the event study validated our findings. We conducted a series of robustness checks, such as using only year 2022 as the post-period to avoid influence from COVID-19. We performed a series of subgroup analyses to examine the heterogeneity in the effects stratified by gender, race, ethnicity, referral sources, prior treatment history, comorbidity, and age groups. We constructed parallel trends to validate the difference-in-difference assumption. 

Medicare coverage on OUD treatment under the SUPPORT Act significantly changed treatment patterns toward non-intensive outpatient services while decreasing use of intensive and inpatient services, however, leading to lower overall treatment completion. Policymakers and healthcare providers should consider strategies to integrate outpatient and inpatient OUD services to ensure continuity of care, promoting treatment engagement and improved outcomes among Medicare beneficiaries with OUD. 

Authors

• Junjie Gai, University of Iowa
  Presenting Author

• Kanika Arora, University of Iowa
  Non-Presenting Co-Author