Past-focused therapies are typically delivered individually, and include the use of exposure techniques in which the client is exposed to reminders of the trauma. Exposure-based treatments have long been considered the ‘gold standard’ in treating PTSD [833, 834]. Similar to exposure for phobias, exposure therapy for PTSD involves gradual exposure to the feared object or situation; in this case, traumatic memories. Traditionally, exposure therapy for PTSD was considered inappropriate for people with AOD use disorders based on beliefs that the emotions experienced may be overwhelming and could lead to more substance use [835]. However, the evidence suggests that this is not the case; exposure therapy does not lead to an exacerbation of AOD use or increase the severity of the AOD use disorder [836]. On the contrary, exposure therapy has been shown to be protective with regards to relapse among people with alcohol use disorders 6-months post-treatment [837].
A number of clinical researchers have begun investigating the efficacy of integrated exposure-based programs that address PTSD and AOD use simultaneously. Typically this involves psychoeducation regarding each disorder and their interrelatedness, coping skills training, relapse prevention, and imaginal and/or in vivo exposure (i.e., exposure to memories and physical reminders of the trauma respectively) [288, 838-840]. Support for these programs is growing, with an increasing number of studies providing evidence for their safety and efficacy. Participants in these studies did not demonstrate a worsening of symptoms or high rates of relapse; on the contrary, they demonstrated improvements in relation to both AOD use and PTSD outcomes [828, 829, 839, 841, 842]. However, the extant research is largely limited to small pilot studies, with only two large RCTs published to date, both of which were conducted in Australia [828, 829].
Mills and colleagues [828] examined the efficacy of an integrated exposure-based therapy called COPE among individuals with a range of AOD use disorders. The authors found that COPE led to significantly greater reductions in PTSD severity compared to treatment as usual for AOD use, at that this reduction in PTSD symptoms was accompanied by significant reductions in AOD use and severity of dependence. A detailed guide to this treatment has been published by Back and colleagues [288]. Sannibale and colleagues [829] compared the efficacy of integrated CBT for PTSD and alcohol use with supportive counselling for alcohol use. Participants who had received one or more sessions of exposure therapy exhibited a twofold greater rate of clinically significant change in PTSD severity compared to those who receive supportive counselling.
In a more recent RCT, Foa and colleagues [837] examined the efficacy of exposure therapy and concurrent naltrexone in treating PTSD and alcohol use disorders. Exposure therapy was not found to be superior to supportive counselling in reducing PTSD symptoms: however, it was associated with reduced risk of relapse at 6-month follow-up. Although no studies have directly compared concurrent treatment with integrated treatment, the results of these trials indicate that integrated treatment may be more efficacious in the treatment of this comorbidity than concurrent treatment.