A 1-μT extremely low-frequency electromagnetic field vs. sham control for mild-to-moderate hypertension: a double-blind, randomized study.
The effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on blood pressure (BP) are controversial. In this double-blind, randomized, sham-controlled study, we examined the effects of repeated exposure to a 1-μT ELF-EMF on BP in 20 humans with mild-to-moderate hypertension. Subjects were randomly assigned to either the ELF-EMF group or the sham group. Subjects in the ELF-EMF group were exposed to an ELF-EMF (6- and 8 Hz, respectively, peak magnetic field 1 μT, peak electric field 10 Vm(-1)) for at least two 10- to 15-min sessions per week, over a period of 4 weeks. In the sham group, the EMF-generating apparatus was not active. We obtained systolic and diastolic BP (SBP and DBP, respectively) measurements at registration and before and after each ELF-EMF exposure session. Subjects in the ELF-EMF and sham groups had mean ages of 52.8 and 55.1 years, and were exposed to a mean of 9.9 and 9.0 sessions, respectively. There was a significant difference between the ELF-EMF and sham groups with respect to change in SBP value between baseline and the end of the exposure regimen (P=0.02), but not with respect to change in DBP (P=0.21). There were no adverse events other than mild paresthesia of the hands of two subjects in the ELF-EMF group. Our results suggest that repeated exposure to an ELF-EMF has a BP-lowering effect on humans with mild-to-moderate hypertension.
Department of Clinical Trial Design and Management, Translational Research Center, Graduate School of Medicine, Kyoto University, Kyoto, Japan. t246ra@kuhp.kyoto-u.ac.jp
Tsutomu
T
Nishimura
Harue
H
Tada
Xinfeng
X
Guo
Toshinori
T
Murayama
Satoshi
S
Teramukai
Hideyuki
H
Okano
Junichi
J
Yamada
Kaneo
K
Mohri
Masanori
M
Fukushima
D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D004311:Double-Blind Method; D005260:Female; D006225:Hand / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000628:therapy*; D055909:Magnetic Field Therapy; D008297:Male; D008875:Middle Aged; D010292:Paresthesia / Q000209:etiology; D016896:Treatment Outcome