Systematic review and meta-analysis of retention in treatment using medications for opioid use disorder by medication, race/ethnicity, and gender in the United States.

BACKGROUND AND AIMS: There is mounting evidence that opioid use disorder is experienced differently by people of different genders and race/ethnicity groups. Similarly, in the US access to specific medications for opioid use is limited by gender and race/ethnicity. This study aims to evaluate if gender or race/ethnicity is associated with different rates of treatment retention in the US, for each of three medications used to treat opioid use disorder.

METHODS

A systematic search was conducted using PubMed, CINHAL, and PsychINFO, databases. All studies that provided a ratio of those retained in treatment at a specified time in terms of gender and/or race/ethnicity and medication were included. Variables were created to assess the effects of time in treatment, recruited sample, required attendance at concurrent psychosocial treatment, and adherence to strict rules of conduct for continuation in treatment on retention. Meta-analytical and meta-regression methods were used to compare studies on the ratio of those who completed a specific time in treatment by race/ethnicity group and by gender.

RESULTS

Nineteen articles that provided the outcome variable of interest were found (11 buprenorphine, six methadone, and two naltrexone). Meta-analyses found that treatment retention was similar for all gender and racial/ethnic groups for all three medications. Meta-regression found that those of the African American group who were recruited into buprenorphine treatment were retained significantly longer than African Americans in buprenorphine treatment who were studied retrospectively. Also, both genders had significantly lower retention in methadone treatment when there was the additional requirement of psychosocial therapy.