Receipt of Opioid Prescriptions from Both VA and Medicare Part D Associated with Greater Likelihood of Death from Overdose
Veterans are at increased risk of opioid use disorders and experience fatal accidental overdoses at nearly twice the rate of adults in the U.S. population. The association between dual VA and Medicare prescription use and unsafe prescribing is well established, but no prior study has evaluated the association between dual use and adverse health outcomes of unsafe prescribing, such as overdose mortality. This case-control study assessed the association between dual receipt of opioid prescriptions from VA and Medicare Part D and prescription opioid overdose death among Veterans enrolled in both VA and Part D. Linking national patient-level data from VA and the Centers for Medicare and Medicaid Services (CMS) in calendar years 2011 to 2013, investigators identified all Veterans enrolled in both VA and Part D who filled â‰¥1 opioid prescription from either system (n=3,237,354). Cause of death was determined using the National Death Index from 2013. The 215 Veterans who died from prescription opioid overdose from 2012-2013 were matched (up to 4-to-1) with 833 non-decedent controls based on date of death, socio-demographics, Medicaid/low-income subsidy, managed care enrollment, region of residence (including rurality), and comorbidities. Patterns of prescription opioid use and safety of use were then assessed across three categories: dual use, VA only, and Part D only.
- Receipt of opioid prescriptions from both VA and Part D was associated with 2-3 times greater odds of overdose death than among Veterans receiving opioids from VA or Part D only.
- Dual users also had a higher cumulative opioid dose over 180 days and average daily opioid dose.
- The main results remained essentially unchanged in sensitivity analyses that varied model specifications, including focusing on fee-for-service Medicare dual enrollees only, adjusting for substance use diagnoses, and categorizing dual use based on any medication and not only opioids.
- Overall, 60 (28%) cases and 117 (14%) controls received dual opioid prescriptions.
- Dual enrollees are a vulnerable group of Veterans, emphasizing the importance of care coordination across providers and healthcare systems to increase the safety of opioid prescribing within and outside VA.
- Studies of opioid use (and its consequences) within VA will not capture all prescriptions a Veteran is taking unless non-VA medication data are included.
- Death certificate data have limitations, including varied data accuracy across states.
- Due to the age of the data, findings may not accurately reflect contemporary effect estimates.
- Investigators were unable to identify opioid prescriptions obtained outside VA or Medicare Part D.
This study was funded by HSR&D. Drs. Zhao, Thorpe and Gellad are part of HSR&D's Center for Health Equity Research & Promotion (CHERP).
Moyo P, Zhao X, Thorpe C, et al. and Gellad WF. Dual Receipt of Prescription Opioids from VA and Medicare Part D and Prescription Opioid Overdose Death among Veterans: A Nested Case-Control Study. Annals of Internal Medicine. March 12, 2019; Epub ahead of print.