PTSD: Evidence-Based Psychotherapy and Emerging Treatment Approaches

Through repeated exposure to feared yet safe stimuli and memories surrounding the trauma, exposure therapy aims for the patient to experience a decrease in fear and an increase in mastery. Prolonged exposure, the most widely used and validated protocol of exposure therapy, incorporates imaginal and in vivo exposures, processing, psychoeducation, and breathing relaxation (see Figure 1 for a case study of prolonged exposure for PTSD) (16). Only exposure therapy displayed the necessary level of evidence required to be recommended by the Institute of Medicine in their highly rigorous review of 90 RCTs for PTSD (5). For chronic PTSD (presence of symptoms for at least 3 months), prolonged exposure was most efficacious in 24 randomized and nonrandomized CBT trials (17). More recently, Powers and colleagues’ meta-analysis of exposure therapy versus control conditions for PTSD treatment demonstrated exposure therapy as superior, with large effect sizes for measures of treatment response (18). However, exposure therapy was not significantly different from other active treatments (CPT, EMDR, stress inoculation training, or cognitive therapy) in terms of PTSD symptom improvement. That exposure therapy was similar in efficacy to other forms of CBT corresponds to previous meta-analytic reviews comparing CBT and psychotherapy treatment approaches for PTSD (13, 19, 20). Even though these different CBT-based treatments are similar in their inclusion of some exposure techniques, more research is needed to understand why they appear to be equally efficacious despite different protocols. Regardless, exposure therapy’s efficacy is not in doubt as all of the major treatment guidelines as well as the IOM’s critique of the scientific rigor of the PTSD treatment literature recommend exposure therapy as a first-line PTSD intervention, and it appears to be equally effective across different demographics and traumas (1, 2, 5, 21).

CPT emphasizes changing a patient’s maladaptive cognitions related to his or traumatic experience (see Figure 2 for a case study of CPT for PTSD). Although there are some similarities to prolonged exposure, such as exposure and psychoeducation, CPT instead uses a writing narrative form of exposure that seeks to help the patient identify and reshape their maladaptive thoughts (22). There is strong support for CPT from several rigorous reviews and various treatment guidelines. When compared with exposure therapy, CPT has been shown to be equally efficacious (13, 18–21). Most of the major PTSD treatment guidelines recommend CPT with a first-level rating (2). Furthermore, CPT appears versatile in applicability, having been well tested with interpersonal traumas, as group therapy, and with emerging efficacy for combat veterans with chronic PTSD and in traumatized refugee populations (15, 23, 24). While not as frequently studied as exposure therapy, CPT remains an evidence-based, highly efficacious treatment option, and both prolonged exposure and CPT are being disseminated throughout the VA Healthcare system as empirically supported treatments.

EMDR offers a broader approach in a treatment that involves exposure and cognitive therapy but with additional bilateral stimulation, usually in the form of saccadic eye movements. There is some debate regarding the necessity of eye movements in EMDR, with some proposing that the exposure component is the active therapeutic mechanism. Ignoring the mechanism debate, the treatment literature shows EMDR to be efficacious for PTSD. Most of the treatment guidelines recommend EMDR as a first-level psychotherapeutic approach with good evidence for PTSD treatment, with two key exceptions being the IOM and American Psychiatric Association (1). Although not warning against EMDR, the IOM cited a lack of adequate evidence to recommend it for treating PTSD (17). Recently, however, a review of seven RCTs of EMDR from the 2000s and an additional review of seven known meta-analyses involving EDMR treatment studies noted that EMDR showed efficacy for treating PTSD in all of these studies and was essentially comparable to exposure therapy and other forms of CBT (25). The evidence base supporting EMDR is growing, and it appears to be strong enough to suggest that it is an efficacious first-line psychological treatment for PTSD.

Most research on other forms of CBT have focused on stress inoculation training (SIT), which aims to help patients manage their anxiety when confronting their traumatic memory or other trauma-related stimuli. Although far less studied than exposure therapy, CPT, or EMDR, meta-analyses that have included SIT approaches found it efficacious and with clinically significant effects (13). There are some recommendations for SIT from the major treatment guidelines, but it is important to note that its study has been limited to civilian populations (2). Other forms of CBT that combine techniques such as cognitive therapy and exposure have been studied, but these are not theoretically different from the predominant CBT approaches used for PTSD: exposure therapy, CPT, and EMDR.

The evidence for other forms of psychotherapy (e.g., psychodynamic) is sparse and lacking in well controlled studies and RCTs. While there is much anecdotal and clinical support for psychodynamic psychotherapy, to this date, only one RCT has shown positive results (26). Brom and colleagues’ RCT of hypnosis and psychodynamic psychotherapy found both to be superior to wait-list control conditions for reducing PTSD symptoms (26). While some PTSD treatment guidelines (e.g., the VA/DOD and International Society for Traumatic Stress Studies) note that there is some use for psychodynamic approaches, the most rigorous reviews of the PTSD psychotherapy literature state that the evidence is insufficient to recommend psychodynamic psychotherapy or hypnosis (2, 5, 19).

There are several other treatment approaches that have been utilized for PTSD such as acceptance and commitment therapy, dialectical behavior therapy (DBT), and skills training in affective and interpersonal regulation (STAIR), with some theoretical basis. Despite their rationale and efficacy for treating other disorders, acceptance and commitment therapy and DBT have positive findings only from case studies, while STAIR from just one clinical trial (27). Overall, these more novel treatments show promise but require more evidence to recommend their use for treatment of PTSD.

Still relatively novel, there is emerging evidence for various MEP approaches from several RCTs. Essentially, MEP involves some combination of a drug with psychotherapy. The approaches used vary from medications that may contribute additional benefit to others designed to facilitate the psychotherapy without directly targeting PTSD symptoms. Thus far, the most well studied MEP approach is SSRI-augmented prolonged exposure, which has shown mixed yet promising results in three published RCTs. The initial RCT first assigned each patient to sertraline, later randomizing to continued sertraline alone or sertraline combined with prolonged exposure, finding that only partial SSRI responders experienced added improvement when receiving prolonged exposure (28). Next, Simon and colleagues found no additional benefit of adding an SSRI to patients that initially received prolonged exposure (29). Administering an SSRI and prolonged exposure simultaneously, Schneier and colleagues’ more recent RCT found paroxetine and prolonged exposure together superior to prolonged exposure alone (with placebo), although differences disappeared at the follow-up assessments (30). These studies are difficult to compare because each used a different design; however, psychotherapy such as prolonged exposure may be useful for those who fail to respond to SSRI pharmacotherapy. Furthermore, the fact that simultaneous treatment with an SSRI and prolonged exposure showed initially positive results is consistent with anecdotal clinical evidence that many patients in psychotherapy trials are often already taking SSRIs or other psychiatric medications.

Cognitive enhancers are the most commonly used of the MEP approaches that aim to make the psychotherapy more effective without acting directly on PTSD symptoms. d-Cycloserine, an antibiotic originally used for treating tuberculosis, heightens glutamate activity and cell change processing in brain pathways associated with fear memory and extinction learning (31). The most commonly studied cognitive enhancer for PTSD treatment, with seven active studies (clinicaltrials.gov), d-cycloserine augmentation with prolonged exposure has shown mixed results in two published RCTs for PTSD, despite promising initial findings (32). While de Kleine and colleagues found that d-cycloserine augmented prolonged exposure patients were more likely to respond to treatment and that more severely symptomatic patients exhibited superior improvement gains than patients receiving PE with placebo (33), Litz and colleagues’ results of an RCT of d-cycloserine and prolonged exposure were entirely negative (34). Perhaps further replication will provide more consistent, positive results for d-cycloserine MEP, but it could be a viable alternative treatment for difficult to treat populations. Based on their efficacy in extinction training, the other cognitive enhancers theorized to be used as MEP for PTSD are hydrocortisone, yohimbine, and methylene blue. These medications currently have no clinical data for PTSD treatment but have four ongoing PTSD treatment trials (35).

Although, like d-cycloserine, methylenedioxymethamphetamine (MDMA or ecstasy) as a form of MEP is thought to facilitate psychotherapy, its theorized mechanism of action is entirely different. Specifically, MDMA boosts serotonin levels, thereby decreasing inhibition, increasing empathy, and creating a sense of euphoria, effects which may promote more active engagement in psychotherapy, exposure in particular (35). Currently, only two RCTs of MDMA augmented psychotherapy for PTSD have been published, both examining treatment resistant populations, with some conflicting results. While 83% of MDMA MEP patients responded to treatment in the first such RCT (36), the most recent study did not find statistically significant improvement but did observe clinically significant improvement (37). Because MDMA’s behavioral effects are rather conspicuous, researchers in these studies may not have been truly blind to the patient’s randomization assignment, thereby potentially influencing the results (35). Should researchers, however, be able to find that the potential risk from neurotoxicity of MDMA is minimal and find ways to safely administer MDMA outside of a highly controlled research setting, then this MEP approach could prove very promising.

Psychotherapy has traditionally been conducted in person and usually on an individual, rather than group, basis. Because patients may not have access to properly trained clinicians or may be unwilling to try some evidence-based treatments, researchers are innovating treatments to include nonindividualized and technologically based options.

Complementary and alternative medicine (CAM) interventions include therapies not considered to be standard practice in the United States, but are considered part of traditional medical practice in other parts of the world and are widely used by consumers (47). Evidence-based treatments may carry issues of acceptability, appropriateness, accessibility, and the stigma of a mental health clinic setting. Accordingly, CAM approaches have risen in popularity as evidenced by the 438 unpublished, recently completed, or ongoing studies (47). Surveys estimate CAM therapy usage at approximately 36%–38% in the general population and 45% in active duty military, who most commonly use massage and relaxation for stress and pain management (48). Ninety-six percent of VA specialized PTSD treatment programs report use of at least one CAM treatment (49).

In response to the rising popularity of CAM treatments, Strauss and colleagues (46) reviewed the RCTs of CAM for PTSD, finding most of the studies of poor quality. Promising results have been found for meditation, acupuncture, and relaxation for improving PTSD symptoms; however, with the exception of the data on acupuncture, studies were methodologically flawed due to a lack of control groups, unclear randomization and blinding procedures, and small sample sizes (49, 50). Other popular approaches such as yoga or service animals are lacking in empirical data (40). For now, CAM techniques may best be utilized as ancillary approaches for patient self-care, but more evidence is needed before they can be recommended as stand-alone treatments.