Social risk factors in the aetiology, maintenance and treatment of opioid use disorder

Abstract

Opioid use disorder (OUD) is a growing global concern as overdoses have drastically increased over recent years. There is an urgent requirement for novel and more effective treatments. Investigating the role of social factors in the onset and maintenance of OUD may be a promising approach. In Chapter 1, I review the role of social vulnerability factors in OUD, and how social functioning may be altered in opioid drug users via changes to the endogenous opioid system. In Chapter 2, I report greater pleasurable effects and reduced aversive effects of an acute dose of morphine in individuals with histories of childhood trauma (without histories of OUD). This suggested history of childhood trauma may increase the rewarding value of opioids, and therefore be a major vulnerability factor preceding OUD. Impairments to social functioning in those with OUD is then investigated in Chapter 3, where I report reduced empathy for others’ emotions alongside greater anger following social exclusion. These findings indicate social risk factors and impaired social functioning as an important area that should be considered in the search for novel treatments for OUD. In Chapter 4 I report on a brief intervention of compassion-focused therapy (CFT) for OUD, showing that this novel treatment is feasible and tolerable in this population. Another potential therapeutic avenue to improve social functioning is by using MDMA adjunct to psychotherapy, therefore in Chapter 5 I examined whether social functioning is negatively affected by MDMA use. Low level, repeated MDMA use was associated with improved empathy and did not affect social distress, highlighting it as potentially suitable for treating social impairments in OUD. In Chapter 6, I discuss the wider theoretical implications and propose a social risk factor model for OUD. I also discuss the clinical implications of the findings, potential limitations to the work, and suggestions for future directions for improving social functioning in OUD. In conclusion, social functioning is disrupted in OUD, and experiences of childhood trauma and social stressors may prime people to the addictive effects of these drugs; however, CFT or MDMA-assisted psychotherapy may be beneficial for treating OUD.