The effects of slow deep breathing on microvascular and autonomic function and symptoms in adults with irritable bowel syndrome: A pilot study

Slow, deep breathing intervention improved symptoms and altered rectal sensitivity in patients with constipation-predominant irritable bowel syndrome

BACKGROUND AND AIM

Limited treatment options have been shown to alter the natural course of irritable bowel syndrome (IBS). Slow, deep breathing (SDB) is a common pain self-management intervention. This pilot study aimed to explore the impact of SDB on measures of autonomic and anorectal functions as well as patient-reported symptoms in constipation-predominant IBS (IBS-C).

METHODS

Eighty-five IBS-C patients were enrolled in this study and randomly assigned to the experimental group (Group A, n = 42) and the control group (Group B, n = 43). SDB was conducted at six breathing cycles per minute with an inhalation for 4 s and exhalation for 6 s at a ratio of 2:3 and repeated for 30 min during the intervention. All subjects underwent high-resolution anorectal manometry (HRAM) and completed the standardized IBS symptom severity system (IBS-SSS) questionnaire. Meanwhile, changes in stool consistency, weekly frequency of complete spontaneous bowel movements (CSBMs), and weekly frequency of spontaneous bowel movements (SBMs) were recorded. All IBS-C patients received electrocardiogram (ECG) recordings for heart rate variability (HRV) analysis at baseline, weeks 3, 6.

RESULTS

At baseline, no differences were found between Groups A and B. The IBS-SSS score and its five sub-scores of Group B patients were significantly higher at week 6 than those of Group A patients (all p < 0.001). Furthermore, compared with Group B patients, Group A patients had a significantly higher threshold volume for the first sensation (p < 0.001), desire to defecate (p = 0.017), and maximum tolerable volume (p = 0.018) at week 6 of the SDB treatment. We also noted significant improvements in stool consistency (p = 0.002), weekly SBM frequencies (p < 0.001), and weekly CSBM frequencies (p = 0.018) of Group A patients at week 6 when compared with Group B patients. Finally, the corrected high frequency (HF) of Group A patients was significantly higher than the HF of Group B patients at week 3 (p < 0.001) and at week 6 (p < 0.001). Likewise, patients in Group A had a significantly higher root mean square of the successive differences (RMSSD) than that of patients in Group B at week 3 (p < 0.001) and at week 6 (p < 0.001).

CONCLUSION

We found that a 6-week SDB intervention improved symptoms and altered rectal sensation in IBS-C patients. Moreover, SDB enhanced vagal activity. These findings suggest that the effect of SDB on IBS-C may be due to mechanisms involving autonomic responses.

Heart Rate Variability-An Index of the Efficacy of Complementary Therapies in Irritable Bowel Syndrome: A Systematic Review

Irritable bowel syndrome (IBS), as a functional and psychosomatic disease, reduces the quality of life and increases the risk of developing mental disorders. Deregulation of the autonomic nervous system (ANS) is one of the main causes of the disease. The objective of the present study was to identify the studies in which measurements of heart rate variability (HRV) were performed before and after therapeutic intervention, and to evaluate the effectiveness of IBS therapy in terms of a reduction of IBS symptoms and changes in autonomic tone. A systematic review of the literature was carried out in accordance with PRISMA standards. Six databases were searched for articles published before 2022: PubMed^®, MEDLINE^®, EBSCO, Cochrane, Scopus, and Web of Science. Inclusion criteria were experimental design, diagnosis of IBS (medical and/or diagnosis in accordance with the Rome Criteria), non-pharmacological intervention, and HRV measurement before and after the intervention. The quality of the studies was assessed by JBI Critical appraisal. In total, 455 studies were identified, of which, sixwere included in the review. Expected changes in HRV (increase in parasympathetic activity) were observed in four of the six studies (interventions studied: ear acupressure, transcutaneous auricular vagusnerve stimulation, cognitive behavioral therapy with relaxation elements, yoga). In the same studies, therapeutic interventions significantly reduced the symptoms of IBS. The present review indicated that interventions under investigation improve the efficiency of the ANS and reduce the symptoms of IBS. It is advisable to include HRV measurements as a measure of the effectiveness of interventions in IBS therapy, and to assess autonomic changes as a moderator of the effectiveness of IBS therapy.