Neuromodulation Applied to Diseases: The Case of HRV Biofeedback

Area of Science:

• Neuroscience
• Cardiology
• Psychophysiology

Background:

• The vagus nerve, a key component of the parasympathetic nervous system, regulates vital organ functions.
• Heart-rate variability (HRV) parameters non-invasively reflect vagal nerve activity.
• Elevated vagal activity is linked to improved mortality, cardiovascular health, and cancer survival.

Purpose of the Study:

• To review the biological mechanisms of vagal activity and HRV in major health conditions.
• To evaluate the effectiveness of HRV-biofeedback (HRV-B) interventions across various diseases.
• To assess the methodological quality of existing HRV-B studies.

Main Methods:

• Narrative literature review of biological mechanisms.
• Systematic search for HRV-B intervention studies.
• Assessment of clinical outcomes and study quality.

Main Results:

• HRV-B shows high evidence of benefit in coronary heart disease (CHD), pain, and hypertension.
• Moderate evidence supports HRV-B in cancer treatment.
• Limited evidence exists for HRV-B in diabetes and dementia.

Conclusions:

• HRV-B is a promising non-invasive technique for self-activating the vagus nerve.
• The efficacy of HRV-B varies across different health conditions, with stronger support for cardiovascular and pain management.
• Further high-quality research is needed, particularly for diabetes and dementia.