Understanding comorbidity between PTSD and substance use disorders: two preliminary investigations.

While there is high level of comorbidity of PTSD and substance use disorders (SUDs), little research has focused on the overlapping symptom constellation characteristic of both PTSD and substance use/withdrawal. This report describes two preliminary investigations that address this area. In the first study, the pattern of PTSD symptoms in a sample of women (n = 28) seeking treatment for a SUD and comorbid with PTSD was compared with the symptom pattern of a sample of women (n = 28) with PTSD only. The PTSD + SUD group evidenced significantly more symptoms in the avoidance and arousal symptom clusters than the PTSD-only group. At the individual symptom level, the PTSD + SUD group reported significantly more sleep disturbance than the PTSD-only group. It was also determined that the PTSD + SUD group reported greater traumatic-event exposure than the PTSD-only group. In the second study, PTSD symptoms were compared in a sample of alcohol- dependent and a sample of cocaine-dependent individuals with PTSD. The alcohol- dependent group exhibited significantly more arousal symptoms than the cocaine-dependent group. Implications of the results for the assessment of individuals with comorbid PTSD and SUDs are discussed.