Introduction: People with intellectual disability (ID) face increased vulnerability to addictive behaviours, yet effective interventions are under-researched. This study aimed to systematically review existing interventions for substance use and problem gambling in this population.
Methods: Following PRISMA guidelines, we searched Web of Science, PsycINFO and CENTRAL for studies on substance use or gambling tailored for people with ID. Two independent reviewers synthesised the data and assessed the methodological quality using established tools.
Results: Sixteen studies were included: three randomised controlled trials (RCTs), six non-randomised trials and seven case studies. Most studies involved small samples of male adults with mild ID, focusing on tobacco (n = 6), polydrug use (n = 5), alcohol (n = 3), opioids (n = 1) or gambling (n = 1). Mindfulness-based therapy and cognitive behavioural therapy combined with motivational interviewing showed promising results for reducing tobacco and alcohol use in people with ID. Short-term benefits were observed for alcohol and cannabis use, though impacts on severity were unclear. Psychoeducation was frequently integrated with behavioural techniques, contributing to reduced substance use through enhanced awareness and knowledge.
Conclusions: The evidence for interventions targeting substance use and gambling in individuals with ID remains limited. A meta-analysis was not possible due to insufficient data, though single-case designs provided valuable insights. More rigorous and comprehensive research is needed to better understand and improve intervention strategies for addressing substance use and gambling problems in people with ID.
Trial registration: PROSPERO CRD42023477296.
Keywords: addiction; gambling; intellectual developmental disorder; intervention; substance use; systematic review.
© 2025 The Author(s). Journal of Intellectual Disability Research published by MENCAP and John Wiley & Sons Ltd.