Aims:

American deaths from opioid overdose now approach 50,000 annually. While evidence shows that medications for addiction treatment (MAT) save lives, retaining patients in MAT programs is challenging. The U.S. Agency for Healthcare Research and Quality, on behalf of the U.S. Department of Health and Human Services, commissioned a rapid evidence review on the effectiveness of interventions to promote a broader understanding of the published literature on MAT retention among adults with opioid use disorder (OUD).

Methods:

We searched MEDLINE and the Cochrane Library from February 12, 2009, through August 20, 2019, for systematic reviews (SRs) and randomized controlled trials (RCTs). We summarized evidence for six retention intervention types: care settings/services/logistical support, contingency management, health information technology (IT), extended-release (XR) medication-based treatment, psychosocial support, and financial support. Our primary outcome was retention, defined as continued medication engagement for at least 3 months after MAT initiation. Secondary outcomes included mortality and harms.

Findings:

Key findings from 2 SRs and 39 primary studies include:

• Most studies of MAT for OUD do not focus on retention as the primary outcome, are small (e.g., one to two trials per intervention), and have design flaws.
• Care setting interventions that initiated MAT in soon-to-be-released incarcerated patients improved retention following release.
• Contingency management improved retention when combined with antagonist MAT, but not with agonist forms of MAT. Applicability, however, may be limited due to implementation challenges.
• Preliminary trials suggest that retention in MAT supported with health IT approaches may be no worse than in-person approaches.
• Early studies suggest no difference in retention with XR–buprenorphine in either injectable or implant formulations compared with daily buprenorphine. There were conflicting results with XR-naltrexone injection compared with daily buprenorphine.
• The addition of psychosocial interventions did not improve retention; however, many studies included some form of counseling in the control groups, potentially obscuring evidence of effectiveness.

Harms were infrequently reported across studies except in studies of XR formulations. Similarly, few studies reported whether participant characteristics influenced retention.

Conclusions:

While patients who receive longer-term treatment with MAT have improved outcomes, fewer than half of the identified studies measured treatment retention as a primary outcome. Limited evidence suggests criminal justice prerelease MAT initiation and the use of contingency management for patients on antagonist forms of MAT may aid retention. XR and daily buprenorphine formulations appear to be equivalent for treatment retention and comparisons of XR–naltrexone versus daily buprenorphine showed conflicting results. Integrating MAT treatment with medical and social services and the use of health IT did not change retention. Some studies were conducted outside of the United States, where policies and practices differ, focused on highly selected populations and/or conditions that are not fully representative of the spectrum of OUD, or were studied in situations that may not be easily implemented in real-world conditions. There is a critical need for studies that use standardized definitions of retention, include measures of harms as well as benefits, and reflect the full spectrum of real-life conditions.