Prolonged Exposure Therapy Showed Some Advantages in Treating PTSD

Authors Didn’t Recommend It Over CPT, However

WHITE RIVER JUNCTION, VT — Post-traumatic stress disorder is a prevalent and serious mental health problem among veterans. Of the veterans who received VA healthcare in 2019, 12.1% had PTSD, including 26.5% of veterans who served in Iraq or Afghanistan.

Although there are a number of effective treatments for PTSD, there is little information about their comparative effectiveness to guide clinicians and their patients. A new study led by researchers at the National Center for PTSD in White River Junction, VT, provides insight into the two leading trauma-focused cognitive behavioral psychotherapies used for VA patients with PTSD: prolonged exposure (PE) and cognitive processing therapy (CPT).

The new VA study assessed the comparative value of the two therapies among veterans with military-related PTSD recruited from outpatient mental health clinics at 17 VA medical centers across the United States from Oct. 31, 2014, to Feb. 1, 2018, with follow-up through Feb. 1, 2019. The 916 participants were randomized to either PE or CPT, delivered according to a flexible protocol of 10 to 14 sessions. The primary outcome was change in PTSD symptom severity on the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) from before treatment to the mean after treatment across post-treatment and three- and six-month follow-ups. Secondary outcomes included other symptoms, functioning and quality of life.¹

PTSD severity on the CAPS-5 improved substantially in both PE and CPT. Mean improvement was greater in PE than CPT, but the difference was not clinically significant. Results for self-reported PTSD symptoms were comparable with CAPS-5 findings. The PE group had higher odds of response and remission compared with the CPT group.

“It looks like there is some advantage to prolonged exposure, but in the broader context we saw some good improvement from both therapies, and they are much more similar than they are different,” said Paula Schnurr, PhD, executive director of the National Center for PTSD and the study’s lead author.

For that, reason, in the paper the authors do not recommend one over the other but say their findings highlight the importance of shared decision-making between the clinician and the patient.

Understandably, patients may prefer one treatment over the other, said Schnurr, who is also professor of psychiatry at the Geisel School of Medicine at Dartmouth. “Both treatments help a person process, and both focus on thoughts and feelings, but prolonged exposure focuses more on feelings as a way to help the patient change those feelings and the thoughts associated with them.

“PE involves repeatedly and vividly recounting the traumatic experience in a safe way, where they are not pushed beyond what they can actually do,” she said. “CPT, in contrast, works on changing thoughts that people have developed. It involves writing sheets that help you objectively analyze your thoughts. For some people, the repletion [of prolonged exposure] is more appealing to them to having to fill out sheets.”

The authors touted the study as the largest randomized clinical trial of PE and ever conducted, pointing out, “Both treatments resulted in meaningful decreases in clinician-rated PTSD severity, the primary outcome. PE was more effective than CPT, but the difference was not clinically significant. There were comparable findings for self-reported PTSD severity. PE was more likely to result in treatment response, loss of diagnosis and remission, but, owing to administrative error, these outcomes were not preregistered and therefore must be interpreted with caution. Treatments did not differ on measures of other symptoms, functioning or quality of life.”

Researchers suggested that PE might have had better outcomes because sessions were 90 minutes long, compared to 60 minutes for CPT. The PE group had more early completers and higher treatment dropout than the CPT group, according to the report. The high percentage (58%) of Iraq and/or Afghanistan war veterans, who are more likely than other veterans to drop out of PE and CPT in VA care, made for a higher dropout rate in general, researchers explained.

Schnurr said the group’s research is now focusing on who is most likely to benefit from one or the other therapy, with the eventual goal of tailoring the treatment to the individual patient.

“We hear a lot about precision medicine these days, often in the context of treatment for cancer, but precision medicine can apply to any branch of medicine,” she said. “In terms of mental healthcare, we are at a really early stage of knowing which of two [treatments] might be better for a particular patient. I hope this study will add to knowledge that informs about the patient characteristics that predict treatment responses and that can help us maybe understand more about PTSD and the mechanisms of PTSD.”

But the immediate practical application of the research is that it offers strong findings about the comparative effectiveness of two forms of psychotherapy that can help patients and providers make even more informed choices.

“It is so important in all aspects of medicine for patients to be informed about the treatment options, the risks, benefits and effectiveness to clarify what is important to them, what they want to do,” Schnurr said.

1. Schnurr PP, Chard KM, Ruzek JI, et al. Comparison of Prolonged Exposure vs Cognitive Processing Therapy for Treatment of Posttraumatic Stress Disorder Among US Veterans A Randomized Clinical Trial. JAMA Network Open. Published January 19, 2022. doi:10.1001/jamanetworkopen.2021.36921