RESUMEN
OBJECTIVE: Mind-body exercise (MBE) interventions, such as yoga, are increasingly recognised as an adjunct treatment for trauma-related mental disorders but less is known about their efficacy as a preventative intervention. We aimed to systematically review if, and what type of, MBE interventions are effective at preventing the development of post-traumatic stress disorder (PTSD) or acute stress disorder (ASD) in trauma-exposed populations. DESIGN: Systematic review and meta-analysis. METHODS: A systematic search of MEDLINE, PsycINFO, EMBASE and CENTRAL databases was conducted to identify controlled trials of MBE interventions aimed at preventing the development of PTSD or ASD in high-risk populations. Risk of bias was assessed using the revised Cochrane risk-of-bias and ROBINS-I tools. Pooled effect sizes using Hedges' g and 95% CIs were calculated using random effects modelling for the main meta-analysis and planned subgroup and sensitivity analyses. RESULTS: Six studies (N analysed=399) were included in the final meta-analysis. Overall, there was a small effect for MBE interventions in preventing the development of PTSD (g=-0.25, 95% CI -0.56 to 0.06) among those with previous or ongoing exposure to trauma. Although a prespecified subgroup analyses comparing the different types of MBE intervention were conducted, meaningful conclusions could not be drawn due to the small number of studies. None of the included studies assessed ASD symptoms. CONCLUSION: Limited evidence was found for MBE interventions in reducing PTSD symptomology in the short term. Findings must be interpreted with caution due to the small number of studies and possible publication bias. PROSPERO REGISTRATION NUMBER: CRD42020180375.