title: [Geomagnetic field effects on circadian variability of cardiac rhythm].
abstract: To study the effect of geomagnetic field (GMF) on circadian rhythm of the heart the author has examined 23 healthy children aged 5-16 years (mean age 12 +/- 4.8). All the examinees have undergone 24-h Holter monitoring with assessment of circadian fluctuations n cardiac rhythm variability (CRV). The data obtained on the parameters Mean, SDNN, SDNN = i, SDANN = i, rMSSD and pNN50 were compared to circadian fluctuations of 3-h indices GMF Ap-index in the test day with estimation of paired correlation index (r). Positive and negative relations between CRV and GMF changes were found in 6 and 8 children, respectively. Groups of GMF-sensitive and GMF-negative children were formed. At 10-year follow-up 3 of 7 GMF-sensitive and 6 of 9 GMF-resistant children developed nonspecific diseases. It is suggested that GMF may have a synchronizing effect on cardiac circadian rhythm. The response of cardiac rhythm to fluctuations of GMF is thought an individual chronotype of the body. GMF-resistant group is characterized by self-regulation of cardiac rhythm which determines reduced availability of exogenic synchronizing effects of GMF.
authors.affiliation: Moscow NII of Pediatrics and Pediatric Surgery, Department of Health, Russia.
authors.forename: L M
authors.initials: LM
authors.lastname: Makarov
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002940:Circadian Rhythm / Q000502:physiology*; D018534:Earth, Planet; D015716:Electrocardiography, Ambulatory; D004781:Environmental Exposure; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000502:physiology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008280:Magnetics; D008297:Male; D012016:Reference Values
vernacular_title: Vliianie geomagnitnogo polia na tsirkadnuiu variabel'nost' ritma serdtsa.