Mediators of improved PTSD symptoms in veterans and civilians following a yoga program.

Objective: Although yoga shows some promise as an intervention for post-traumatic stress disorder (PTSD), little is known about how yoga reduces PTSD symptoms. The current study hypothesised that aspects of interoceptive awareness would mediate the effect of a yoga intervention on PTSD symptoms.

Methods: We used data from our recently completed randomised controlled trial of a 16-week holistic yoga programme for veterans and civilians diagnosed with PTSD (n = 141) that offered weekly 90-minute sessions. We conducted a mediation analysis using interoceptive awareness and other variables that were associated with PTSD symptom reduction at mid-treatment and treatment end.

Results: Although measures of anxiety, interoceptive awareness, and spirituality were identified in individual mediator models, they were no longer found to be significant mediators when examined jointly in multiple mediator models. When examining the multiple mediator models, the strongest mediator of the yoga intervention on PTSD symptoms was mental well-being at mid-treatment and stigma at the treatment end. The total effect of yoga on CAPS and PCL at the treatment end mediated by stigma was 37.1% (-1.81/-4.88) and 33.6% (-1.91/-5.68), respectively.

Conclusion: Investigation of mental well-being and mental illness stigma as potential mediators is warranted in future studies of yoga as a treatment for PTSD as they may prove to be important foci for yoga interventions.