摘要：Objectives. To estimate the prevalence and consequences of receiving prescription opioids from both the Department of Veterans Affairs (VA) and Medicare Part D. Methods. Among US veterans enrolled in both VA and Part D filling 1 or more opioid prescriptions in 2012 (n = 539 473), we calculated 3 opioid safety measures using morphine milligram equivalents (MME): (1) proportion receiving greater than 100 MME for 1 or more days, (2) mean days receiving greater than 100 MME, and (3) proportion receiving greater than 120 MME for 90 consecutive days. We compared these measures by opioid source. Results. Overall, 135 643 (25.1%) veterans received opioids from VA only, 332 630 (61.7%) from Part D only, and 71 200 (13.2%) from both. The dual-use group was more likely than the VA-only group to receive greater than 100 MME for 1 or more days (34.3% vs 10.9%; adjusted risk ratio [ARR] = 3.0; 95% confidence interval [CI] = 2.9, 3.1), have more days with greater than 100 MME (42.5 vs 16.9 days; adjusted difference = 16.4 days; 95% CI = 15.7, 17.2), and to receive greater than 120 MME for 90 consecutive days (7.8% vs 3.1%; ARR = 2.2; 95% CI = 2.1, 2.3). Conclusions. Among veterans dually enrolled in VA and Medicare Part D, dual use of opioids was associated with more than 2 to 3 times the risk of high-dose opioid exposure. Prescription opioids claimed more than 183 000 lives in the United States from 2000 to 2015, with millions more suffering the adverse consequences of prescription opioid misuse and abuse. 1–4 As large payers for prescription drugs, both the Department of Veterans Affairs (VA) and the Centers for Medicare and Medicaid Services (CMS) have invested in monitoring potential misuse and abuse of prescription opioids and have instituted numerous changes to improve opioid safety. 5 These efforts, however, have focused predominately on prescriptions dispensed within their own systems. Many veterans receive care from both VA and Medicare, in some cases simultaneously. Referred to as “dual use,” this receipt of care across health care systems is increasingly common. 6–14 More than half of veterans enrolled in the VA are also enrolled in Medicare, a third of whom are also enrolled in the Part D drug benefit. 15 While enrollment in both VA and Medicare may increase access to care, it also creates the opportunity for unsafe opioid use because of care fragmentation. As much as CMS and VA have individually done to address opioid use, these efforts have limited capability to assess prescriptions that beneficiaries receive in the other system. This is especially true given that there is no interface between electronic health records (EHRs) across systems and little communication between prescribers or pharmacies. 16 Although the electronic records for care provided through VA and Medicare do not yet communicate, administrative claims data from both are available for research and linkable at the patient level. This enables a national and comprehensive analysis of the impact of dual use on prescription opioids. We thus obtained Medicare and VA data for all dually enrolled veterans who filled a prescription opioid in either system in 2012 to answer 2 previously unanswered questions: (1) What is the national prevalence of dual use of prescription opioids among dually enrolled veterans? and (2) What is the association between dual use of opioids and evidence-based measures of opioid prescribing safety?
