Structural, functional change
The results did not differ by age, gender, or type of trauma. Dr. Neria noted that many women in the study had suffered sexual abuse or assault, suggesting that the intervention might be appropriate for PTSD outside the military.
“I’m very keen on moving this along into a civilian population,” he said.
The study did not examine potential mechanisms of action. where the treatment took place, the investigators noted.
However, Dr. Neria thinks there is another potential explanation – real changes in the brain.
Neuroimaging of a subsample of 20 participants before and after the intervention showed a significant increase in caudate functional connectivity and a reduction in gray matter density of the thalamus and the caudate.
“We see a big change both structurally and functionally,” with the results pointing to an impact on the reward network of the brain, said Dr. Neria.
“This suggests that pleasure was perhaps the main mechanism of action,” which corresponds with patient reports of really enjoying the experience, he added.
Dr. Neria noted that equine therapy is different from bonding with a loyal dog. Interacting with a large and powerful animal may give veterans a sense of accomplishment and self-worth, which can be tremendously therapeutic.
Next step in therapy?
Commenting on the research, retired Col. Elspeth Cameron Ritchie, MD, chair of psychiatry, MedStar Washington Hospital Center, Washington, called equine therapy “innovative” in PTSD.
Dr. Elspeth Cameron Ritchie
“I see this as the next step in finding acceptable therapies that people like to do,” she said.
Some patients have an aversion to talk therapy because it makes them relive their trauma; and many dislike the side effects of medications, which can include erectile dysfunction, said Dr. Ritchie, who was not involved with the research.
“So something like this that they can enjoy, have a sense of mastery, can bond with an animal, I think is wonderful,” she said.
Dr. Ritchie noted that working with animals offers “a kind of biofeedback” that may calm anxieties, help maintain control, and “is very nonjudgmental.”
However, she pointed out that equine therapy is not new. For example, horses have been used previously to treat patients with a variety of disabilities, including autism.
Dr. Ritchie thought it was “very wise” that study participants just learned to control the horses and didn’t actually ride them, because that could be a frightening experience.
Nonetheless, she noted equine therapy “is not going to be accessible for everybody.”
In addition, Dr. Ritchie was surprised that the investigators didn’t mention more of the quite extensive research that has been conducted on dog therapy in patients with PTSD.
Dr. Neria and Ritchie disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.