Are equine-assisted services beneficial for military veterans with post-traumatic stress disorder? A systematic review and meta-analysis

BACKGROUND: Equine-assisted services (EAS) involves the use of horses within therapy, learning or horsemanship sessions and has been used with military veterans suffering from post-traumatic stress disorder (PTSD). This study systematically reviewed existing research on the use of EAS in the treatment of PTSD in military veterans and evaluated its effectiveness. METHODS: A systematic review was performed, in May 2023, with searches and data extraction carried out from three separate databases (PubMed, JSTOR and Science Direct) related to testing the effect of EAS on PTSD outcomes in veterans. A risk of bias assessment of included studies was conducted and meta-analysis of outcomes performed when two or more studies reported the same outcomes. Other effects of EAS on veterans' health were also discussed. RESULTS: A total of 13 studies were identified based on our inclusion and exclusion criteria with 11 originating from the US and the remaining two from Australia and Israel. There were 344 participants amongst all of the studies with a mean age of 47 years and a male:female ratio of 19:6. Eight out of the 13 studies reported PTSD scores, as measured by either PTSD Checklist for DSM-5 (PCL-5) or PCL-Veteran/-Military versions (PCL-V/-M), and results suggested a reduction in PTSD score after EAS treatment of 22.6%. A meta-analysis confirmed that EAS favored a significantly lower PTSD score after treatment, with a mean difference of 12.46, 95% CI 9.03,15.88, p < 0.00001. However, only one study had low risk of bias whilst all the rest of the studies had some concerns to high risk of bias. CONCLUSIONS: EAS appeared to have a positive influence on PTSD symptoms in military veterans, significantly reducing PTSD severity scores. Other benefits of EAS may be peer support, social integration, learning new skills and bonding. However, the results of this systematic review must be interpreted with caution as almost all of the studies were of low quality. Therefore, further rigorous research is required with larger participants to be able to draw conclusions about the benefits of EAS on PTSD severity.