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Medicaid, United States. Patient Protection and Affordable Care Act, Opioids -- Therapeutic use, Opioid abuse -- Treatment


Background/Aims: Evidence suggests Medicaid beneficiaries in the USA are prescribed opioids more frequently than are people who are privately‐insured, but little is known about opioid prescribing patterns among Medicaid enrollees who gained coverage via the Affordable Care Act Medicaid expansions. This study compared the prevalence of receipt of opioid prescriptions and opioid‐use‐disorder (OUD), along with time from OUD diagnosis to medication‐assisted treatment (MAT) receipt between Oregon residents who had been continuously insured by Medicaid, were newly insured after Medicaid expansion in 2014, or returned to Medicaid coverage after expansion.

Design: Cross‐sectional study using inverse‐propensity weights to adjust for differences among insurance groups.

Setting: Oregon.

Participants: 225,295 Oregon Medicaid adult beneficiaries insured 2014‐2015 and either: 1) newly enrolled, 2) returning in 2014 after a > 12‐month gap, or 3) continuously insured between 2013 and 2015. We excluded patients in hospice care or with cancer diagnoses.

Measurements: Any opioid dispensed, chronic (≥90‐day) and high dose (≥ 90 daily morphine milligram equivalence) opioid use, documented OUD diagnosis, and MAT receipt.

Findings: Compared with the continuously insured, newly and returning insured enrollees were less likely to be dispensed opioids [newly: 42.3%, 95% confidence interval (95%CI) 42.0‐42.7%; returning: 49.3%, 95%CI 48.8‐49.7%; continuously: 52.5%, 95%CI 52.0‐53.0%], use opioids chronically (newly: 12.8%, 95%CI 12.4‐13.1%; returning: 11.9%, 95%CI 11.5‐12.3%, continuously: 15.8%, 95%CI 15.4‐16.2%), have OUD diagnoses (newly: 3.6%, 95%CI 3.4‐3.7%; returning: 3.9%, 95%CI 3.8‐4.1%, continuously: 4.7%, 95%CI 4.5‐4.9%), and receive MAT after OUD diagnosis [Hazard Ratio newly: 0.57, 95%CI 0.53‐0.61; Hazard Ratio returning: 0.60, 95%CI 0.56‐0.65 (REF: continuously)].

Conclusions: Residents of Oregon, USA who enrolled or re‐enrolled in Medicaid health insurance after expansion of coverage in 2014 as a result of the Affordable Care Act were less likely than those already covered to receive opioids, use them chronically, or receive medication‐assisted treatment for opioid use disorder.


This is the peer reviewed version of the following article: Springer, R., Marino, M., Bailey, S. R., Angier, H., O'Malley, J. P., Hoopes, M., Lindner, S., DeVoe, J. E., andHuguet, N. ( 2019) Prescription Opioid Use Patterns, Use Disorder Diagnoses, and Addiction Treatment Receipt after the 2014 Medicaid Expansion in Oregon. Addiction,

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