Mood disturbance and withdrawal severity in substitution treatment for opioid dependence: Their association and impact on continued illicit drug use

Abstract

Objectives: This study explored the relationship between withdrawal severity and mood disturbance, and their links with continued illicit drug use during the first 3 months of opioid substitution treatment (ST). Methods: Sixteen participants undergoing opioid ST with methadone (n=7) or buprenorphine (n=9) were recruited through outpatient units in South Australia. In a within-groups repeated measures design, the Opiate Treatment Index was administered at baseline and again at 3 months. Participants also completed the Methadone Symptoms Checklist and the Profile of Mood States at baseline and fortnightly throughout the 3-month measurement period. Results: Withdrawal severity and mood disturbance were observed to co-vary over the 3 months. Statistically significant reductions in both withdrawal severity and mood disturbance were observed. The direction of association between withdrawal severity and mood disturbance was positive and was statistically significant at all measurement points. Continued use of illicit drugs was associated with higher levels of both mood disturbance and withdrawal severity. Conclusions: Withdrawal severity and mood disturbance co-vary over time and have important implications for treatment outcomes in ST.