Long-term follow-up assessment of opioid use outcomes among individuals with comorbid mental disorders and opioid use disorder treated with buprenorphine or methadone in a randomized clinical trial.
Mental disorders among individuals with opioid use disorder (OUD) are common. The purpose of this study was to investigate whether there were differential effects on opioid use among OUD patients with specific life-time psychiatric diagnoses (mood disorder, mental disorder other than mood disorder, none) who received medication treatment for OUD (MOUD) with either methadone (MET) or buprenorphine (BUP).
In a randomized controlled trial (CTN-0027, the START study), adults with OUD were randomized to 24 weeks of either BUP or MET treatment and were followed up in 3-yearly assessments. The present secondary analyses of data from CTN-0050 (Long-Term Follow-Up of START Patients) were based on 597 participants who completed all assessments.
The outcome measure was the number of days of using opioids per month during the follow-up period. The Mini-International Neuropsychiatric Interview (MINI) was used to classify participants into three groups: lifetime mood disorder (n=302), lifetime mental disorder other than mood disorder (n=114), and no mental disorder (n=181). Medication treatment (BUP, MET, no treatment) during the follow-up period was a time-varying predictor.
Based on zero-inflated Poisson (ZIP) mixed regression analysis, it was found that relative to no treatment, opioid use during the follow-up was significantly reduced by BUP and by MET. Relative to MET, BUP was associated with a lower likelihood of any opioid use among participants with mood disorders and for participants without mental disorder, and fewer number of days using opioids among participants with other mental disorders.
Conclusions: Among adults with comorbid opioid use disorder and mental disorders, treatment with buprenorphine-naloxone produced greater reductions in opioid use than treatment with methadone.
Related protocols: CTN-0027, CTN-0050