Increased Prevalence of Childhood Complex Trauma in Comorbid Posttraumatic Stress Disorder and Substance Use Disorders Compared to Either Disorder Alone: A Systematic Review.

Objective: Childhood complex trauma (CCT) prevalence among individuals with comorbid posttraumatic stress disorder (PTSD) and substance use disorder (SUD) is unknown. We conducted a meta-analysis to compare CCT prevalence in samples of PTSD alone, SUD alone and comorbid PTSD+SUD.

Method: A systematic review of PTSD, CCT and SUD literature was conducted using online databases. Binary outcome meta-analytic models were fitted comparing CCT prevalence in comorbid PTSD + SUD to PTSD and SUD only.

Results: Seven studies were included, and estimates for CCT prevalence were higher, on average, among individuals with comorbid PTSD+SUD (35%-78%) compared to PTSD alone (4%-70%) and SUD alone (2%-65%). A meta-analysis of four studies indicated individuals with comorbid PTSD+SUD were 18% more likely to have experienced CCT compared to individuals with PTSD only (RR = 1.18, 95% CI [1.13, 1.25]) and 24% more likely compared to individuals with SUD only (RR = 1.24, 95% CI [1.20, 1.29]).

Conclusions: Further research is needed to establish a more accurate prevalence rate for individuals with comorbid PTSD and SUD. Evidence of greater CCT prevalence will inform research study design and clinical targets during treatment for individuals with comorbid PTSD and SUD.