Neuromodulation Applied to Diseases: The Case of HRV Biofeedback

Author: Asaf Gitler1, Leen Vanacker2, Marijke De Couck2, Inge De Leeuw2, Yoram Gidron1
1 Faculty of Social Welfare and Health Sciences, Department of Nursing, University of Haifa, Haifa 3498838, Israel.
2 Faculty of Medicine and Pharmacy, Department of Public Health, Mental Health and Wellbeing Research Group, Free University of Brussels (VUB), 1140 Evere, Belgium.
Conference/Journal: J Clin Med
Date published: 2022 Oct 8
Other: Volume ID: 11 , Issue ID: 19 , Pages: 5927 , Special Notes: doi: 10.3390/jcm11195927. , Word Count: 196

The vagus or "wandering" nerve is the main branch of the parasympathetic nervous system (PNS), innervating most internal organs crucial for health. Activity of the vagus nerve can be non-invasively indexed by heart-rate variability parameters (HRV). Specific HRV parameters predict less all-cause mortality, lower risk of and better prognosis after myocardial infarctions, and better survival in cancer. A non-invasive manner for self-activating the vagus is achieved by performing a slow-paced breathing technique while receiving visual feedback of one's HRV, called HRV-biofeedback (HRV-B). This article narratively reviews the biological mechanisms underlying the role of vagal activity and vagally mediated HRV in hypertension, diabetes, coronary heart disease (CHD), cancer, pain, and dementia. After searching the literature for HRV-B intervention studies in each condition, we report the effects of HRV-B on clinical outcomes in these health conditions, while evaluating the methodological quality of these studies. Generally, the levels of evidence for the benefits of HRV-B is high in CHD, pain, and hypertension, moderate in cancer, and poor in diabetes and dementia. Limitations and future research directions are discussed.

Keywords: biofeedback; cancer; clinical outcomes; coronary heart disease; heart-rate-variability (HRV); hypertension; pain; vagally mediated HRV (vmHRV); vagus nerve.

PMID: 36233794 DOI: 10.3390/jcm11195927