Changes in comorbid conditions after prolonged exposure for PTSD: a literature review

Prolonged exposure (PE) is an effective psychological treatment for patients who suffer from PTSD. The majority of PTSD patients have comorbid psychiatric disorders, and some clinicians are hesitant to use PE with comorbid patients because they believe that comorbid conditions may worsen during PE. In this article, we reviewed the evidence for this question: what are the effects of PE on comorbid symptoms and associated symptomatic features? We reviewed findings from 18 randomized controlled trials of PE that assessed the most common comorbid conditions (major depression, anxiety disorders, substance use disorders, personality disorders, and psychotic disorders) and additional symptomatic features (suicidality, dissociation, negative cognitions, negative emotions, and general health and work/social functioning). Although systematic research is not available for all comorbid populations, the existing research indicates that comorbid disorders and additional symptomatic features either decline along with the PTSD symptoms or do not change as a result of PE. Therefore, among the populations that have been studied to date, there is no empirical basis for excluding PTSD patients from PE due to fear of increases in comorbid conditions or additional symptomatic features. Limitations of the existing research and recommendations for future research are also discussed.