Effect of slow, deep breathing on visceral pain perception and its underlying psychophysiological mechanisms

Author: Ali Gholamrezaei1,2,3, Ilse Van Diest2, Qasim Aziz4, Ans Pauwels5, Jan Tack5, Johan W S Vlaeyen2,6, Lukas Van Oudenhove1
1 Laboratory for Brain-Gut Axis Studies (LaBGAS), Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium.
2 Health Psychology Research Group, KU Leuven, Leuven, Belgium.
3 Pain Management Research Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
4 Centre for Neuroscience and Trauma, Blizard Institute, Wingate Institute of Neurogastroeneterology, Queen Mary University of London, London, UK.
5 Gastrointestinal Sensitivity and Motility Research Group, Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium.
6 Experimental Health Psychology, Maastricht University, Maastricht, The Netherlands.
Conference/Journal: Neurogastroenterol Motil
Date published: 2021 Aug 11
Other: Special Notes: doi: 10.1111/nmo.14242. , Word Count: 253

Studies using somatic pain models have shown the hypoalgesic effects of slow, deep breathing. We evaluated the effect of slow, deep breathing on visceral pain and explored putative mediating mechanisms including autonomic and emotional responses.

Fifty-seven healthy volunteers (36 females, mean age = 22.0 years) performed controlled, deep breathing at a slow frequency (6 breaths per minute), controlled breathing at a normal frequency (14 breaths per minute; active control), and uncontrolled breathing (no-treatment control) in randomized order. Moderate painful stimuli were given during each condition by delivering electrical stimulation in the distal esophagus. Participants rated pain intensity after each stimulation. Heart rate variability and self-reported arousal were measured during each condition.

Key results:
Compared to uncontrolled breathing, pain intensity was lower during slow, deep breathing (Cohen's d = 0.40) and normal controlled breathing (d = 0.47), but not different between slow, deep breathing and normal controlled breathing. Arousal was lower (d = 0.53, 0.55) and heart rate variability was higher (d = 0.70, 0.86) during slow, deep breathing compared to the two control conditions. The effect of slow, deep breathing on pain was not mediated by alterations in heart rate variability or arousal but was moderated by pain catastrophizing.

Conclusions and inferences:
Slow, deep breathing can reduce visceral pain intensity. However, the effect is not specific to the slow breathing frequency and is not mediated by autonomic or emotional responses, suggesting other underlying mechanisms (notably distraction). Whether a long-term practice of slow, deep breathing can influence (clinical) visceral pain warrants to be investigated.

Keywords: autonomic nervous system; baroreflex; breathing exercises; pain; vagus nerve.

PMID: 34378834 DOI: 10.1111/nmo.14242