Time sequence of autonomic changes induced by daily slow-breathing sessions

• Published in: Clinical autonomic research Vol. 25; no. 2; pp. 95 - 104
• Main Authors: Modesti, Pietro Amedeo, Ferrari, Antonella, Bazzini, Cristina, Boddi, Maria
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2015; Springer Nature B.V
• Subjects: Adult; Aged; Autonomic Nervous System - physiopathology; Blood Pressure - physiology; Cardiology; Diabetes; Endocrinology; Essential Hypertension; Female; Gastroenterology; Humans; Hypertension - physiopathology; Hypertension - rehabilitation; Male; Medicine; Medicine & Public Health; Middle Aged; Neurology; Ophthalmology; Research Article; Respiration; Hypertension; Complementary therapies; Breathing exercises; Prevention and control; Autonomic nervous system; Baroreflexes
• ISSN: 0959-9851; 1619-1560
• DOI: 10.1007/s10286-014-0255-9

Objective Daily sessions of slow-breathing (6 breaths/min) significantly reduced 24-h ambulatory blood pressure (ABP) in patients with mild hypertension and this effect persisted at least 6 months after the interruption of sessions. The sequence of changes induced by slow-breathing (SB) daily sessions on the modulation of ambulatory blood pressure, renal resistive index, heart rate variability (HRV), and baroreflex sensitivity (BRS) was thus investigated in a randomized, controlled clinical trial. Methods Thirty-seven patients (30–75 years, grade I essential hypertension), untreated with antihypertensive drugs, were randomized to daily sessions (30 min) of music-guided SB (<10 breaths/min) (intervention, n  = 24) or simple relaxation (control, n  = 13). Office and ambulatory blood pressure monitoring renal Doppler ultrasound, assessment of BRS (sequence method and spectral analysis), and HRV (spectral power in the high- and low-frequency bands) were performed at baseline, and after 1, 4, and 8 weeks. Mixed model analysis was conducted on derived variables given by the difference between each measurement and the baseline value within subjects. Results After 1 week, the intervention enhanced the parasympathetic modulation (high-frequency power; at least p  < 0.05 vs both control and baseline) and reduced renal vascular resistance ( p  < 0.05 for both comparisons); after 1 month, the enhancement of BRS ( p  < 0.05 for both comparisons at both methods) paralleled a significant reduction in 24 h ABP ( p  < 0.05 for all comparisons). Interpretation Repeated daily session of music-guided SB increased parasympathetic modulation and decreased renal resistive index early in the study. These changes were being followed by a positive modulation of BRS and blood pressure reduction.