Long-Term Effect of Device-Guided Slow Breathing on Blood Pressure Regulation and Chronic Inflammation in Patients with Essential Hypertension Using a Wearable ECG Device

Author: Chen-Hsu Wang1,2, Hui-Wen Yang3, Han-Luen Huang1,4, Cheng-Yi Hsiao1, Bun-Kai Jiu1, Chen Lin1,5, Men-Tzung Lo1,5
Affiliation: <sup>1</sup> Institute of Translational and Interdisciplinary Medicine, National Central University, Taoyuan. <sup>2</sup> General Cardiology &amp; Coronary Care Unit, Cardiovascular Center, Cathay General Hospital. <sup>3</sup> Graduate Institute of Communication Engineering, National Taiwan University, Taipei. <sup>4</sup> Department of Cardiology, Hsinchu Cathay General Hospital, Hsinchu. <sup>5</sup> Center for Biotechnology and Biomedical Engineering, National Central University, Taoyuan, Taiwan.
Conference/Journal: Acta Cardiol Sin
Date published: 2021 Mar 1
Other: Volume ID: 37 , Issue ID: 2 , Pages: 195-203 , Special Notes: doi: 10.6515/ACS.202103_37(2).20200907A. , Word Count: 257


Background:
Hypertension is related to autonomic nervous system (ANS) dysfunction, atherosclerosis and chronic inflammation. The stimulation of baroreflex regulation by slow-breathing exercise may improve the interplay among these systems. The objective of this study was to investigate the effect of device-guided slow breathing on ANS, cardiovascular system and chronic inflammation in hypertensive patients.

Methods:
We prospectively collected 36 essential hypertension patients who were requested to practice slow-breathing exercise 5 times per day for 3 months. The breathing exercise was guided by a cellphone app with a wearable electrocardiography device and a rhythm of 6 cycles per minute. Cardiovascular indicators including heart rate variability (HRV), blood pressure, pulse wave velocity and baroreflex indexes were sampled 3 times: at the first visit, and 1 month and 3 months after the intervention. The levels of blood inflammatory biomarkers, including tumor necrosis factor-alpha (TNF-α), interleukin-6, interleukin-1 receptor antagonist and C-reactive protein were also collected at all 3 visits. The longitudinal differences in these variables and their correlations were tested.

Results:
There was a significant decrease in blood pressure after 1 month of exercise. A significantly continuous decrease in TNF-α was also observed. The baroreflex indexes were significantly increased in the acute intervention of slow-breathing but not in the longitudinal effect. The HRV variables did not show differences with time. There were positive correlations between sympathetic index and TNF-α and galectin-3.

Conclusions:
The effect of slow-breathing exercise on blood pressure and chronic inflammation was significant. HRV indexes may also be used to assess chronic inflammation.

Keywords: Atherosclerosis; Autonomic function; Baroreflex; Chronic inflammation; Hypertension; Slow breathing.

PMID: 33716462 PMCID: PMC7953112 DOI: 10.6515/ACS.202103_37(2).20200907A