Substance use disorders in patients with posttraumatic stress disorder: A review of the literature

Objective: Alcohol use disorders and other substance use disorders are extr emely common among patients with posttraumatic stress disorder (PTSD). This article reviews studies pertaining to the epidemiology, clinical phenomeno logy, and pathophysiology of comorbid PTSD and substance use disorders. Method: Studies were identified by means of computerized and manual searche s. The review of research on the pathophysiology of PTSD and substance use disorders was focused on studies of the hypothalamic-pituitary-adrenal axis and the noradrenergic system. Results: High rates of comorbidity suggest that PTSD and substance use diso rders are functionally related to one another. Most published data support a pathway whereby PTSD precedes substance abuse or dependence. Substances a re initially used to modify PTSD symptoms. With the development of dependen ce, physiologic arousal resulting from substance withdrawal may exacerbate PTSD symptoms, thereby contributing to a relapse of substance use. Preclini cal work has led to the proposal that in PTSD, corticotropin-releasing horm one and noradrenergic systems may interact such that the stress response is progressively augmented. Patients may use sedatives, hypnotics, or alcohol in an effort to interrupt this progressive augmentation. Conclusions: Vigorous control of withdrawal and PTSD-related arousal sympto ms should be sought during detoxification of patients with comorbid PTSD an d substance use disorders. Inclusion of patients with comorbid PTSD and sub stance use disorders in neurobiologic research and in clinical trials will be critical for development of effective treatments for this severely sympt omatic patient population.