Posttraumatic stress disorder (PTSD) is diagnosed in more than 25% of patients seeking treatment for chronic pain; a similar pattern is seen in patients seeking treatment for substance abuse. The purpose of this study was to examine how patients with PTSD and a history of substance abuse (SA+PTSD), and patients with PTSD and chronic pain (CP+PTSD) differed on a self-report measure to assess frequency and severity of PTSD symptoms.

Study participants were assessed using the Modified PTSD Symptom Checklist (MPSS), and were determined to meet the PTSD symptom criteria. The substance abuse patients were twenty-two men and eleven women involved in substance abuse treatment programs. The average age of the SA+PTSD group was 32.79 years, most were single (42.3%), some married (30.8%), and some divorced or separated (26.9%). Nineteen men and ten women referred to a work-related injury rehabilitation program made up the CP+PTSD group. Average age of this group was 34.76 years, most were married (72.4%), some single (23.1%), and one (3.4%) separated or divorced. The two groups had similar demographics, differing only on marital status.

All participants completed the MPSS self-report scale based on the 17 symptoms from the DSM-IV diagnostic criteria. This assessment allowed participants to report on the severity and frequency of their symptoms.

The authors found that the CP+PTSD group reported greater severity scores for nine of seventeen PTSD symptoms. The SA+PTSD group reported greater frequency scores for eight of seventeen PTSD symptoms. The authors hypothesize that "...patients with CP+PTSD were hyperaware of bodily sensations, resulting in greater severity scores." In addition the authors suggest that, "it is possible that patients with comorbid PTSD and substance abuse were self-medicating, resulting in lower reported severity scores."

In conclusion, the authors state:

"The aforementioned findings hold important implications for treating patients with PTSD. Because we found that groups differed on severity and frequency of PTSD symptoms, it may be prudent to tailor treatment focus to the symptom presentations characteristics of each disorder (e.g., avoidance symptoms). However, since participants were not assessed with a structured clinical interview, we cannot determine whether other comorbid disorders influenced the reports obtained by our participants (e.g., depression). Further research incorporating a structured clinical interview and more detailed psychiatric evaluations is clearly warranted in order to clarify factors that mediate and/or moderate differences in symptom presentation when PTSD occurs with other syndromes."

Bonin M, Norton G, Frombach I, Asmundson G. PTSD In Different Treatment Settings: A Preliminary Investigation of PTSD Symptomology In Substance Abuse and Chronic Pain Patients. Depression and Anxiety 2000;11:131-133.