Lock-in programs connect patients to drug treatment, but don’t reduce risk of opioid overdose

September 17, 2019

Lock-in programs for individuals at risk for opioid misuse appear to have little effect on overdoses — a finding that points to a need for improved program design.

Dr. Becky Naumann

Becky Naumann, PhD, assistant professor of epidemiology at the UNC Gillings School of Global Public Health, is lead author of “Evaluation of a Medicaid Lock-in Program: Increased Use of Opioid Use Disorder Treatment but No Impact on Opioid Overdose Risk,” which was published in the March 2019 issue of Medical Care.

Lock-in programs, also called patient review and restriction programs, identify individuals at risk for overusing opioids and other controlled substances. They then restrict access to these medications by requiring patients to use a single prescriber and/or pharmacy to obtain such drugs.

Through enrollment in lock-in programs, providers can identify individuals who could benefit from opioid use disorder treatment, such as medication-assisted treatment (MAT).

To examine the effects of a Medicaid lock-in program on 1) use of MAT for opioid use disorder and 2) on overdose risk, Naumann and her team analyzed North Carolina Medicaid claims from July 2009 to June 2013. They estimated daily risk differences and ratios of MAT use and overdose during the lock-in period and following release from the program, compared with periods before program enrollment.

The team found that while the lock-in programs may have been useful for increasing connections to MAT, there did not appear to be an impact on average overdose risk across this population.

“In previous studies, we found that the average amount of opioids dispensed to individuals, measured in terms of average daily morphine milligram equivalents, increased during program enrollment,” says Naumann. “And we know that it’s also a possibility that program restrictions may lead some people to use substances outside of the health care system.”

According to Naumann, lock-in or patient restriction programs are too often a one-size approach for a complex problem. They don’t account for the range of substance use trajectories following enrollment in the program, which could be a function of both patient characteristics and behaviors as well as those of their providers. The extent to which program restrictions may influence enrollees to obtain substances outside of the health care system is unknown and could also affect overdose risk across these periods.

“Ideally, lock-in programs would result in improved care coordination, connection to appropriate opioid use disorder treatment as needed and reduction in overdose,”  she says. “Although our findings suggested an average increase in medication-assistant treatment, these increases did not couple with overdose decreases.”

Identifying facilitators of MAT access and use among this population, as well as potential barriers to overdose reduction, are important next steps in designing successful lock-in programs.

“Promising lock-in-program models include tailored case management approaches that treat and address the many complex needs of the patient, including comorbidities, as well as factors such as housing and transportation,” Naumann adds. “We need to move away from a one-size-fits-all approach to a more patient-focused approach.”

Contact the Gillings School of Global Public Health communications team at sphcomm@unc.edu.