The effects of heart rate variability biofeedback as an adjunct to therapy on trauma symptoms

Many individuals with PTSD exhibit autonomic hyperarousal. Additionally, the autonomic nervous system has shown disruption characterized by increased sympathetic activity and decreased parasympathetic tone, as measured by heart rate variability (HRV). Consequently, physiological reflexes are likely to not work as well, leaving traumatized individuals unable to deal effectively and efficiently with new stressors. The purpose of this study was to investigate whether HRV biofeedback improved symptoms related to post traumatic stress disorder (PTSD) when added to therapy addressing trauma symptoms. Statistical analyses were used to examine the effects of using an ambulatory respiratory sinus arrhythmia (RSA; a measure of heart rate variability) biofeedback device, StressEraser, compared to progressive muscle relaxation (PMR). Results indicated that HRV did not increase for either group. Trauma symptoms decreased significantly from pre- to post-treatment for both groups indicating that relaxation techniques may be useful as an adjunctive treatment for PTSD. Individuals who scored high on dissociation had significantly higher baseline levels of avoidance, re-experiencing and hyperarousal symptoms. Additionally, there were significant between-group differences between participants who scored high and low on dissociation in the HRV biofeedback group such that those scoring low on dissociation improved in trauma symptoms, while those scoring high on dissociation got worse. This difference was not found between the high and low dissociation groups that received PMR. These findings call for further research to clarify if increasing HRV impacts PTSD symptom severity and to further understand the different responses to HRV biofeedback treatment for individuals with high versus low levels of dissociation.