Context: Childhood trauma is more prevalent among individuals with substance use disorders compared to the general population, representing a significant public health concern. The presence of comorbid dissociative symptoms poses a significant challenge for psychological care.

Objectives: We conducted a systematic review of the literature, using the PRISMA method, to establish the relationship between dissociative experiences and substance misuse in adults who have experienced traumatic childhood events.

Method: We used electronic databases (PubMed, PsycInfo, PsycArticles, Web of Science and ProQuest) up to August 2023. Studies were selected which included adults over 18 years old who had been exposed to one or more traumatic events in childhood, and which jointly assessed Substance Use Disorder (SUD) and dissociation, using quantitative methodology. The review included both cross-sectional and longitudinal studies, with the risk of bias assessed using the AXIS tool and the Qualitative Assessment Tool for Observational Cohort and Cross-Sectional Studies. The results are entered in a table and analyzed using a narrative summary.

Results: Among the 18 included studies, encompassing a total of 6,451 participants, the majority (n = 10) showed a significant positive correlation between dissociative experiences and SUD. The studies collectively indicate a general trend: childhood traumatic antecedents can influence the severity of dissociative symptomatology and SUD.

Discussion: These results are discussed in greater depth in relation to the two main theories explaining the link between SUD and dissociation, namely self-medication and chemical dissociation theory. This paper clarifies the relationship between dissociation and substance use in a population traumatized in childhood, although the heterogeneity of the studies necessitates a cautious interpretation of this primary finding.