Controlled substance lock-in programs are garnering increased attention from payers and policy makers seeking to combat the epidemic of opioid misuse. These programs require high-risk patients to visit a single prescriber and pharmacy for coverage of controlled substance medication services. Despite high prevalence of the programs in Medicaid, we know little about their effects on patients' behavior and outcomes aside from reducing controlled substance-related claims. Our study was the first rigorous investigation of lock-in programs' effects on out-of-pocket controlled substance prescription fills, which circumvent the programs' restrictions and mitigate their potential public health benefits. We linked claims data and prescription drug monitoring program data for the period 2009-12 for 1,647 enrollees in North Carolina Medicaid's lock-in program and found that enrollment was associated with a roughly fourfold increase in the likelihood and frequency of out-of-pocket controlled substance prescription fills. This finding illuminates weaknesses of lock-in programs and highlights the need for further scrutiny of the appropriate role, optimal design, and potential unintended consequences of the programs as tools to prevent opioid abuse.
Bibliographical noteFunding Information:
Findings from this research were presented at the 21st Annual National Research Services Award Trainee Research Conference, Minneapolis, Minnesota, June 14, 2015; the AcademyHealth Annual Research Meeting, Minneapolis, Minnesota, June 16, 2015; and the American Pharmacists Association Annual Meeting and Exposition, San Diego, California, March 28, 2015. This research was supported by the Centers for Disease Control and Prevention (Cooperative Agreement No. CDC U01 CE002160-01); a Clinical and Translational Sciences Award (Grant No. UL1TR000083); the Injury Prevention Research Center at the University of North Carolina at Chapel Hill; the Agency for Healthcare Research and Quality, via a National Research Service Award T32 Postdoctoral Fellowship for Andrew Roberts, sponsored by the Cecil G. Sheps Center for Health Services Research at UNCChapel Hill (Grant No. 5T32 HS000032); and the American Foundation for Pharmaceutical Education, via a Predoctoral Fellowship in the Pharmaceutical Sciences for Roberts. The authors thank Leslie Moss for her invaluable technical support for this research.