{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T14:37:25Z","timestamp":1790433445952,"version":"4.1.0"},"reference-count":22,"publisher":"American Medical Association (AMA)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"<jats:sec id=\"ab-zoi251587-4\">\n                    <jats:title>Importance<\/jats:title>\n                    <jats:p>Patient Protection and Affordable Care Act (ACA) Medicaid expansion has been linked to improved uptake of medications for opioid use disorder (MOUD) access for Medicaid enrollees, but evidence is limited on the associations of post-2018 expansions with population-level treatment. Moreover, prior studies have not implemented modern staggered-adoption estimators or examined outcomes by payer type, risking biased and incomplete inference.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-5\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To evaluate the association of Medicaid expansion with buprenorphine treatment rates (overall and by payer) across all expansion states using updated data and methods and to test whether post-2018 expansions (post\u2013X-waiver and telehealth era) differed from earlier ones.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-6\">\n                    <jats:title>Design, Setting, and Participants<\/jats:title>\n                    <jats:p>Cross-sectional study of buprenorphine dispensing in participants aged 18 years or older from 2013 to 2024 using the IQVIA Longitudinal Prescription Database containing over 90% of US retail pharmacy claims across 51 US jurisdictions (50 states plus Washington, DC). Cross-sectional difference-in-differences analysis leveraging staggered adoption of changes in monthly buprenorphine MOUD dispensing rates associated with Medicaid expansion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-7\">\n                    <jats:title>Exposure<\/jats:title>\n                    <jats:p>Medicaid expansion under the ACA, implemented state-by-state, covering 41 expansion states (plus DC) and 10 nonexpansion states, measured by state and month.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-8\">\n                    <jats:title>Main Outcomes and Measures<\/jats:title>\n                    <jats:p>The primary outcome was the state-month rate of unique individuals receiving 1 or more buprenorphine prescriptions for opioid use disorder per 100\u202f000 residents (all-payer). Secondary outcomes were payer-specific rates\u2014Medicaid, commercial, Medicare, and self-pay\u2014each per 100\u202f000 persons in the corresponding insured population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-9\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>As the first year of any expansion is 2014, 2013 served as the baseline year. In 2013, there were 659\u202f046 unique patients, 58.2% were male, and the mean (SD) age was 36.6 (0.02) years. For 149\u202f648\u202f295 dispensations for 4\u202f596\u202f264 unique patients across 41 expansion states (including DC) and 10 nonexpansion states from 2013 to 2024, Medicaid expansion increased total buprenorphine treatment rates only in states expanding in 2019 or later (21.1% relative increase; average treatment effect on the treated, 28.67 per 100\u202f000; 95% CI, 8.20-49.15 per 100\u202f000). Gains were most pronounced in high-need recent expanders, such as Maine (57.22 per 100\u202f000; 95% CI, 44.20-70.24 per 100\u202f000), Virginia (44.46 per 100\u202f000; 95% CI, 31.44-57.49 per 100\u202f000), and Oklahoma (22.98 per 100\u202f000; 95% CI, 12.84-33.12 per 100\u202f000).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"ab-zoi251587-10\">\n                    <jats:title>Conclusions and Relevance<\/jats:title>\n                    <jats:p>In this cross-sectional study using contemporary data and methods, post-2018 Medicaid expansions were associated with substantial increases in buprenorphine treatment, particularly in high-need states operating under newer prescribing regulations. These findings underscore Medicaid expansion\u2019s role in improving opioid use disorder treatment access and can inform state and federal efforts to expand evidence-based care.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2025.59803","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T16:30:33Z","timestamp":1771432233000},"page":"e2559803","source":"Crossref","is-referenced-by-count":3,"title":["Medicaid Expansion and Buprenorphine Dispensing in Early vs Recent Expansion States"],"prefix":"10.1001","volume":"9","author":[{"given":"Nicole","family":"Siegal","sequence":"first","affiliation":[{"name":"O\u2019Neill School of Public and Environmental Affairs, Indiana University, Bloomington"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sumedha","family":"Gupta","sequence":"additional","affiliation":[{"name":"Department of Economics, Indiana University Indianapolis, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Miles","sequence":"additional","affiliation":[{"name":"Center for Health Services Research, Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, New Brunswick, New Jersey"},{"name":"Department of Family Medicine and Community Health, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hillary","family":"Samples","sequence":"additional","affiliation":[{"name":"Center for Pharmacoepidemiology and Treatment Science, Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, New Brunswick, New Jersey"},{"name":"Rutgers School of Public Health, Piscataway, New Jersey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosali","family":"Simon","sequence":"additional","affiliation":[{"name":"O\u2019Neill School of Public and Environmental Affairs, Indiana University, Bloomington"},{"name":"National Bureau of Economic Research, Cambridge, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew C.","family":"Aalsma","sequence":"additional","affiliation":[{"name":"Children\u2019s Health Services Research Division, Department of Pediatrics, Indiana University School of Medicine, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Crystal","sequence":"additional","affiliation":[{"name":"Center for Health Services Research, Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, New Brunswick, New Jersey"},{"name":"School of Social Work, Rutgers University, New Brunswick, New Jersey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","published-online":{"date-parts":[[2026,2,18]]},"reference":[{"issue":"25","key":"zoi251587r4","doi-asserted-by":"publisher","first-page":"567","DOI":"10.15585\/mmwr.mm7325a1","article-title":"Treatment for opioid use disorder: population estimates\u2014United States, 2022.","volume":"73","author":"Dowell","year":"2024","journal-title":"MMWR Morb Mortal Wkly Rep"},{"issue":"6","key":"zoi251587r5","doi-asserted-by":"publisher","first-page":"567","DOI":"10.1007\/s40263-019-00637-z","article-title":"Buprenorphine treatment for opioid use disorder: an overview.","volume":"33","author":"Shulman","year":"2019","journal-title":"CNS Drugs"},{"key":"zoi251587r6","doi-asserted-by":"publisher","DOI":"10.1016\/j.dadr.2023.100193","article-title":"Differences in medicaid expansion effects on buprenorphine treatment utilization by county rurality and income: a pharmacy data claims analysis from 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