{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T16:04:40Z","timestamp":1790006680256,"version":"4.0.1"},"reference-count":36,"publisher":"American Medical Association (AMA)","issue":"9","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"\n Importance<\/jats:title>\n Appropriate medication management can prevent adverse outcomes, yet medication nonadherence remains common, including among patients with diabetes.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To examine racial and ethnic disparities in medication adherence among Medicare Advantage (MA) enrollees with diabetes and assess factors contributing to these disparities.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n Using the Medicare Master Beneficiary Summary File and MA encounter data, this cohort study included MA enrollees with Part D coverage in 2019 and a documented diabetes diagnosis from January 1, 2017, to December 31, 2018, who filled at least 1 prescription for metformin, insulin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, or a glucagon-like peptide-1 receptor agonist (GLP-1 RA) in 2019. Analysis was conducted between December 2024 and November 2025.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n Unadjusted and adjusted disparities in adherence (proportion of days covered \u226580%) during 2019 were examined for insulin, metformin, and SGLT2 inhibitors and\/or GLP-1 RAs, distinguishing within-plan disparities from differences between plans serving proportionately more vs fewer Black or Hispanic enrollees. Oaxaca-Blinder decomposition analysis estimated the contribution of covariates to adherence disparities.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Among 587\u202f716 total beneficiaries (mean [SD] age, 72.11 [8.85] years), analyses of disparities between Black and White enrollees included 80\u202f586 Black (63.3% female) and 233\u202f505 White (50.9% male) beneficiaries; analyses of disparities between Hispanic and White enrollees included 83\u202f116 Hispanic (53.9% female) and 190\u202f509 White (51.1% male) beneficiaries. In unadjusted analyses, adherence was lower among Black beneficiaries than among White beneficiaries: \u22129.0 percentage points [pp] for SGLT2 inhibitors and\/or GLP-1 RAs, \u22128.0 pp for insulin, and \u221210.5 pp for metformin (all\n P<\/jats:italic>\n \u2009&amp;lt;\u2009.001). Adherence was also lower among Hispanic beneficiaries than among White beneficiaries: \u22128.1 pp for SGLT2 inhibitors and\/or GLP-1 RAs, \u22122.8 pp for insulin, and \u22123.6 pp for metformin (all\n P<\/jats:italic>\n \u2009&amp;lt;\u2009.001). By medication type, within-plan disparities accounted for 74.6% to 85.3% of adherence disparities between Black and White enrollees and 39.1% to 66.1% of disparities between Hispanic and White enrollees. Medicaid or Low-Income Subsidy enrollment was associated with reductions in disparities between Black and White enrollees (22.0% for insulin and 32.3% for SGLT2 inhibitors and\/or GLP-1 RAs) and Hispanic and White enrollees (63.9% for insulin and 41.3% for SGLT2 inhibitors and\/or GLP-1 RAs).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n This retrospective cohort study of MA enrollees with diabetes found racial and ethnic disparities in diabetes medication adherence. Disparities in adherence to insulin or SGLT2 inhibitors and\/or GLP-1 RAs were partially mitigated by Medicaid and prescription drug subsidies but less so by plan-level factors. The findings suggest that additional insurance- and community-level strategies are needed to improve medication adherence among disadvantaged patients and communities.<\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2026.34846","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T15:30:33Z","timestamp":1790004633000},"page":"e2634846","source":"Crossref","is-referenced-by-count":0,"title":["Racial and Ethnic Disparities in Medication Adherence Among Medicare Advantage Enrollees With Diabetes"],"prefix":"10.1001","volume":"9","author":[{"given":"Utibe R.","family":"Essien","sequence":"first","affiliation":[{"name":"Division of General Internal Medicine and Health Services, David Geffen School of Medicine, University of California Los Angeles"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric T.","family":"Roberts","sequence":"additional","affiliation":[{"name":"Division of General Internal Medicine, University of Pennsylvania, Philadelphia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dominic A.","family":"Ruggiero","sequence":"additional","affiliation":[{"name":"Division of General Internal Medicine, University of Pennsylvania, Philadelphia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jasmyn J.","family":"Tang","sequence":"additional","affiliation":[{"name":"Division of General Internal Medicine and Health Services, David Geffen School of Medicine, University of California Los Angeles"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sindhu","family":"Raghava","sequence":"additional","affiliation":[{"name":"Division of General Internal Medicine, University of Pennsylvania, Philadelphia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John Z.","family":"Ayanian","sequence":"additional","affiliation":[{"name":"Division of General Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor"},{"name":"Institute for Healthcare Policy & Innovation, University of Michigan, Ann Arbor"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renuka","family":"Tipirneni","sequence":"additional","affiliation":[{"name":"Division of General Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor"},{"name":"Institute for Healthcare Policy & Innovation, University of Michigan, Ann Arbor"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"zoi260943r2","doi-asserted-by":"publisher","DOI":"10.1016\/j.pmedr.2025.103157","article-title":"US adults with diagnosed diabetes enrolled in Medicare by age and insurance type.","volume":"56","author":"Bardenheier","year":"2025","journal-title":"Prev Med Rep"},{"key":"zoi260943r3","doi-asserted-by":"publisher","DOI":"10.1016\/j.pmedr.2024.102957","article-title":"Unveiling inequalities: racial, ethnic, and 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