VA-Purchased Community Care and Risk of Potentially Unsafe Concurrent Medication Use Among Veterans Receiving Opioids: A Regression Discontinuity Analysis.

Abstract

Objective: To examine whether eligibility for Veterans Health Administration (VA) community care, which expanded Veterans' access to VA-funded care outside VA, increased the likelihood of Veterans concurrently filling prescriptions for opioids and central nervous system (CNS)-active medications.

Study setting and design: We used a regression discontinuity design to analyze Veterans across a distance threshold for community care eligibility in the Veterans Choice Program, under which Veterans residing > 40 miles from the closest VA medical facility staffed by ≥ 1 full-time primary care physician qualified for community care. We used local linear regression to test whether exceeding this 40-mile threshold was associated with discontinuities in the probability of receiving overlapping supplies of opioids and another CNS medication (benzodiazepine, muscle relaxant, antiepileptic, or sleep aid) for ≥ 30 days per year.

Data sources and analytic sample: We used VA pharmacy data for prescriptions filled at VA facilities, VA Program Integrity Tool files for prescriptions paid by VA and filled in community pharmacies, and Medicare and Medicaid data for prescriptions covered by those programs. Our analysis included annual cross-sectional samples of Veterans who filled ≥ 1 opioid prescription through VA, community care, Medicare, or Medicaid and lived 36-39 or 41-44 miles from the nearest VA facility during federal FYs 2016-2019 (n = 180,903 Veteran-year observations).

Principal findings: Among Veterans who filled an opioid prescription, 34.1% concurrently received another CNS medication for ≥ 30 days. Exceeding the threshold for community care eligibility was associated with a 1.14 percentage point (pp) increase (95% CI: 0.08, 2.20) in the probability of concurrently receiving an opioid and another CNS drug during 2016-2019. Discontinuities in overlap were larger among Veterans with a serious mental illness (2.7 pp.; 95% CI: 0.6, 4.9) during 2016-2019. During 2018-2019, discontinuities were larger in the overall sample (1.6 pp.; 0.0, 3.1) and among non-Hispanic Black Veterans (5.4 pp.; 95% CI: 0.5, 10.4).

Conclusions: Overall, VA community care eligibility was associated with a small increase in medication overlap involving opioids and other CNS-active medications. Increases in overlap were larger in certain Veteran subgroups and later study years, underscoring a need for continued monitoring of higher-risk co-prescribing in VA community care.