The Influence of the Call with a Mobile Phone on Heart Rate Variability Parameters in Healthy Volunteers

The Influence of the Call with a Mobile Phone on Heart Rate Variability Parameters in Healthy Volunteers
http://www.jstage.jst.go.jp/article/indhealth/46/4/46_409/_article

Rszard ANDRZEJAK1), Rafal POREBA1), Malgorzata POREBA2), Arkadiusz DERKACZ1), Robert SKALIK3), Pawel GAC1), Boguslaw BECK1), Aleksandra STEINMETZ-BECK1) and Witold PILECKI2)

1) Department of Internal Medicine, Occupational Disease and Hypertension, Wroclaw Medical University
2) Department of Pathophysiology, Wroclaw Medical University
3) Department of Physiology, Wroclaw Medical University

(Received May 11, 2007)
(Accepted April 8, 2008)

Abstract: It is possible that electromagnetic field (EMF) generated by mobile phones (MP) may have an influence on the autonomic nervous system (ANS) and modulates the function of circulatory system. The aim of the study was to estimate the influence of the call with a mobile phone on heart rate variability (HRV) in young healthy people.

The time and frequency domain HRV analyses were performed to assess the changes in sympathovagal balance in a group of 32 healthy students with normal electrocardiogram (ECG) and echocardiogram at rest.

The frequency domain variables were computed: ultra low frequency (ULF) power, very low frequency (VLF) power, low frequency (LF) power, high frequency (HF) power and LF/HF ratio was determined. ECG Holter monitoring was recorded in standardized conditions: from 08:00 to 09:00 in the morning in a sitting position, within 20 min periods: before the telephone call (period I), during the call with use of mobile phone (period II), and after the telephone call (period III).

During 20 min call with a mobile phone time domain parameters such as standard deviation of all normal sinus RR intervals (SDNN [ms] - period I: 73.94±25.02, period II: 91.63±35.99, period III: 75.06±27.62; I-II: p<0.05, II-III: p<0.05) and standard deviation of the averaged normal sinus RR intervals for all 5-mm segments (SDANN [ms] - period I: 47.78±22.69, period II: 60.72±27.55, period III: 47.12±23.21; I-II: p<0.05, II-III: p<0.05) were significantly increased.

As well as very low frequency (VLF [ms2] - period I: 456.62±214.13, period II: 566.84±216.99, period III: 477.43±203.94; I-II: p<0.05), low frequency (LF [ms2] - period I: 607.97±201.33, period II: 758.28±307.90, period III: 627.09±220.33; I-II: p<0.01, II-III: p<0.05) and high frequency (HF [ms2] - period I: 538.44±290.63, period II: 730.31±445.78, period III: 590.94±301.64; I-II: p<0.05) components were the highest and the LF/HF ratio (period I: 1.48±0.38, period II: 1.16±0.35, period III: 1.46±0.40; I-II: p<0.05, II-III: p<0.05) was the lowest during a call with a mobile phone.

The tone of the parasympathetic system measured indirectly by analysis of heart rate variability was increased while sympathetic tone was lowered during the call with use of a mobile phone.

It was shown that the call with a mobile phone may change the autonomic balance in healthy subjects. Changes in heart rate variability during the call with a mobile phone could be affected by electromagnetic field but the influence of speaking cannot be excluded.

Full Text at: http://www.jstage.jst.go.jp/article/indhealth/46/4/409/_pdf

Ky words: Mobile phone, Heart rate variability (HRV), Electromagnetic field (EMF), Holter monitoring, Autonomic function