Description and evaluation of a manual for heart rate variability biofeedback in somatic stress disorder

Background: There is initial evidence for the efficacy of heart rate variability biofeedback (HRV-BF) in depression, anxiety disorders and functional somatic syndromes. In somatic symptom disorder (SSD) evidence is lacking. The aim of the study was to describe a newly developed HRV-BF brief intervention and to analyze HRV changes, and to examine the applicability and acceptance in SSD. Meth-ods: We analyzed the data of the subsample of a pilot ran-domized controlled trial (22 subjects with SSD) who re-ceived HRV-BF over 4 sessions. We assessed HRV (SDNN: standard deviation of the NN interval, RMSSD: root mean square of successive differences between NN interval, LF: low frequency), and the subjective evaluation and accep-tance of the intervention. Results: HRV analyses within & nbsp;therapy sessions showed that individuals learned to increase their HRV significantly during biofeedback sessions and were able to maintain it during self-regulation periods without feedback (SDNN, RMSSD, LF: 5.7 <_ Ft <_ 11.1). Moreover, HRV improved across sessions (SDNN). The majority of participants rated the intervention very positively (e.g., satisfaction, improvement in mood and physical well-being). Conclusions: HRV-BF can be learned within 4 sessions and shows positive effects in patients with SSD. Adding HRV-BF to existing treatments, e.g. psychotherapy, seems promising.& nbsp;