C. Exposure Therapy (ET)

BACKGROUND

RCTs have shown that Exposure Therapy (ET) helps men and women with PTSD reduce the fear associated with their experience through repetitive, therapist-guided confrontation of feared places, situations, memories, thoughts, and feelings. ET usually lasts from 8 to 12 sessions depending on the trauma and treatment protocol. Patients are repeatedly exposed to their own individualized fear stimuli, until their arousal and fear responses are consistently diminished. In session exposure is often supplemented by therapist-assigned and monitored self-exposure to the memories or situations associated with traumatization. ET providers can vary the pacing and intensity of exposing patients to the most frightening details of their trauma based on the patient's emotional response to the trauma and to the therapy itself.

Exposure can be accomplished via "imaginal" exposure or "in vivo" exposure. Imaginal exposure involves encouraging the patient to revisit the experience in imagination, recalling the experience through verbally describing the emotional details of the trauma. In vivo exposure involves asking the patient to physically confront realistically safe but still feared stimuli (e.g. driving a car after having been in a serious motor vehicle accident). This exposure can also be arranged in a hierarchical fashion. In the preceding example the patient might first sit in a car in the passenger seat, and then in the driver's seat, and then start the car, etc. The patient repeats each situation until a reduction in the intensity of emotional and physiological response is achieved, at which point they move on to the next item in their hierarchy.

DISCUSSION

RCTS of ET have demonstrated its efficacy in female victims of sexual and non-sexual assault, motor vehicle accidents, male combat-related trauma, and mixed trauma populations. Findings regarding efficacy in (mostly Vietnam) combat veterans in VA clinical settings are less consistent and the degree of improvement in PTSD symptoms appears to be less pronounced.

In randomized trials comparing ET with other cognitive behavioral treatments ET has performed as well or better than any cognitive behavioral therapy (CBT) approach. In a comprehensive review of research studies examining CBT for PTSD Rothbaum et al. (2000) found the strongest evidence for exposure therapy. Four studies have found that exposure treatment for PTSD in samples heterogeneous with regard to their traumas has been efficacious. Richards et al. (1994) found that participants with PTSD who were given either four sessions of imaginal exposure followed by four sessions of in vivo exposure, or in vivo followed by imaginal exposure, improved considerably. Marks et al. (1998) found that exposure, cognitive therapy, and their combination were all equally successful in reducing PTSD at posttreatment and 6-month follow-up. Tarrier et al. (1999) found there was a significant improvement on all measures at posttreatment and follow-up, with no significant differences between exposure therapy and cognitive therapy. Thompson et al. (1995) found that 8 weekly sessions of imaginal and in vivo exposure were effective in treating participants with PTSD.

Vietnam combat veterans (uncontrolled study; 15 males) showed significant improvements from pre- to posttreatment on some measures but not on others, when given a comprehensive treatment package consisting of education, individual ET, programmed practice of the exposure, and social and emotional rehabilitation (Frueh et al., 1996, Keane et al., 1989). A large-scale, randomized controlled effectiveness trial was recently completed involving 360 Vietnam combat veterans (reference). This study compared exposure-based CBT with supportive "present-centered" group therapy that did not involve exposure. Results showed that (a) both treatment conditions produced moderate changes in PTSD symptoms from baseline levels and (b) the two treatment conditions were not different from one another in clinical effectiveness. Rates of drop out from treatment were somewhat higher for the ETgroup.

The Expert Consensus Panel for Posttraumatic Stress Disorder (1999) recommended ET for the treatment of intrusive thoughts, flashbacks, trauma related fears, panic attacks, avoidance and generalized anxiety in patients with PTSD, listing it as the quickest acting psychotherapy and one of the two most effective psychotherapies for PTSD. The International Society for Traumatic Stress Studies described ET as "quite effective" in the treatment of a mixed variety of trauma survivors: "In fact, no other treatment modality has evidence this strong indicating its efficacy."

In most treatment settings, ET is delivered as part of a more comprehensive "package" treatment. That is, it is usually combined with PTSD education, coping skills training, and especially, cognitive restructuring. ET and cognitive restructuring are usually regarded as the most powerful components of treatment, although randomized trials comparing ET alone with combined ET and cognitive restructuring suggest that ET alone may be more effective than combined treatment.

There have, as yet, been no randomized trials comparing ET with pharmacotherapy. Therefore, it is not known how ET compares with SSRIs or other medications as effective treatments. Nor is it known whether combined ET plus pharmacotherapy is more effective than either treatment alone.

Patients need to be screened for their suitability prior to undergoing ET as it may temporarily increase their level of distress. Patients living in dangerous circumstances (e.g., domestic violence or a threatening environment) are not candidates for ET until their security can be assured. Other contraindications for ET have not been confirmed in empirical research, but may include health problems that preclude exposure to intense physiological arousal, current suicidal ideation, substance abuse not in stable remission, co-morbid psychosis, or lack of motivation to undergo the treatment. Because this treatment may increase distress and PTSD symptoms in the short term, it is not well accepted by all patients, some of whom may drop out of treatment. Therefore, providers must take concrete steps to prepare patients for the treatment (e.g., present clear rationale, explore patient concerns, encourage realistic expectations, and build commitment to the therapy) in order to reduce the risk of dropout.

Cooper; Ironson; Paunovic & Ost; Resick & Nishith; Schnurr - not supported in Discussion section