Six-month Treatment Outcomes of Cocaine-dependent Patients with and Without PTSD in a Multisite National Trial

Objective: This study examined 6-month treatment outcomes among 428 cocaine-dependent outpatients with (n = 34) and without (n = 394) posttraumatic stress disorder (PTSD) in a randomized controlled multisite clinical trial of manual-based psychotherapies for substance use disorder (SUD).

Method: Assessments were completed at baseline and monthly during the 6-month treatment. With longitudinal mixed-effects models, we compared outcomes between SUD-PTSD and SUD-only patients and also examined rates of within-group change.

Results: Results indicated a highly consistent pattern: the SUD-PTSD patients were more impaired to begin with and remained so across time compared with SUD-only patients (with the exception of substance use and addiction-related legal and employment problems, which did not differ between groups). Also, the SUD-PTSD patients improved less than SUD-only patients in alcohol use and the majority of addiction-related psychosocial problems. However, the two groups did not differ significantly in improvement over time on drug use or global psychological severity.

Conclusions: The greater impairment and relative lack of improvement of SUD-PTSD patients, compared with those with SUD-only, suggest a need for dual-diagnosis treatments that more directly target their areas of difficulty.