A new study from researchers at C.C.N.Y. (City College of New York) examined the connection between improvements in posttraumatic stress and improvement in substance abuse over the course of time in 353 women diagnosed with both conditions.

Participants were randomly assigned to 12 sessions of either trauma-focused treatment or health education.  Assessments were made on the PTS and the substance use during treatment at 1 week and posttreatment after 3, 6, and 12 months.

Subjects showing no improvement, an improvement in the substance use only, or a total, global improvement early on, tended to maintain their original diagnosis over time; but subjects initially exhibiting improvement in their PTSD symptoms were significantly more likely to transition into a global response over time, indicating that they maintained their PTSD improvement, and that it was associated with subsequent improvements in substance use.
 

Additionally, trauma-focused treatment was significantly more effective than the health education method in achieving substance use improvement, but only among those who were heavy substance users at baseline and had achieved significant PTSD reductions.
 
This study concludes that reductions in PTSD severity were more likely to be associated with substance use improvement, but that it did not work the other way around:  reductions in substance abuse did not lead to improved PTSD symptoms. These results support the self-medication model of coping with PTSD symptoms, and an empirical basis for integrated interventions for improved substance use outcomes in patients with severe symptoms.

Citation:  Hien DA, Jiang H, Campbell AN, Hu MC, Miele GM, Cohen LR, Brigham GS, Capstick C, Kulaga A, Robinson J, Suarez-Morales L, Nunes EV. Do treatment improvements in PTSD severity affect substance use outcomes? A secondary analysis from a randomized clinical trial in NIDA's Clinical Trials Network. American Journal of Psychiatry. 2010 Jan; 167(1):95-101. Epub 2009 Nov 16. [email protected]