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Bioelectromagnetism

Cornélissen et al. (2002) claim that the incidence of mortality due to myocardial infarction increases

in Minnesota, USA, by 5% during years of maximal solar activity compared with years of minimum

activity. Tis corresponds to an extra 220 deaths per year (in a population of about 5 million) during

the period of high solar activity. Also reported is a positive correlation of HR and a negative correla­

tion of HRV with solar activity, measured via the sunspot number. Interestingly, the correlation of HR

with sunspot number is signifcant only for the ascending part of the solar cycle. Palmer et al. (2006)

suggested that the increase in HR and decrease in HRV could be a result of aging of the test subject(s).

However, HR normally decreases with age, and there are many other variables that afect HR. Te claim

would be more convincing if there was also an association during the descending part of the cycle.

Cornélissen et al. (2002) also report a 7.6% increase in the incidence of myocardial infarction afer

a reversal of the direction of the N-S component (Bz) of the interplanetary MF. On the following day,

a 5.9% decrease is observed (Cornélissen et al., 2002). A N-S Bz “fip” is known to trigger auroras and

magnetospheric storms (Arnoldy, 1971), with a typical delay of 2 or 3 hours. During such a reversal of the

interplanetary MF, the total current in the magnetosphere increases by a factor of 10, while the potential

diference across the geomagnetic tail and across the polar cap increases from typically 10 to 100 kV.

Cornélissen et al. (2002) conclude that there is the additional risk of myocardial infarction at solar

maximum compared with the solar minimum, which implies an additional risk for high levels of geo­

magnetic activity. Other studies report an additional risk whenever the level of geomagnetic activity

deviates from its “nominal” level. For example, Shumilov et al. (2003) report that not only high levels

but also extremely low levels of geomagnetic activity have an adverse efect on fetal state in Murmansk

at ~65°N magnetic latitude.

More recently, Azcárate and Mendoza (2017) conducted the correlation analysis in a group of eight

adult hypertensive volunteers, four men and four women, with ages between 18 and 27 years in Mexico

City during a geomagnetic storm in 2014, and the results indicated a signifcant correlation between

the SBP and DBP and the atmospheric pressure and the horizontal GMF component, being the largest

during the night (Azcárate and Mendoza, 2017). Te analysis showed that the largest correlations are

between the DBP and DBP and the horizontal GMF component (Azcárate and Mendoza, 2017). Tus,

the superposed epoch analysis showed that the largest number of signifcant changes in the BP under

the infuence of the GMF occurred in the SBP for men (Azcárate and Mendoza, 2017).

Moreover, Gurfnkel et al. (2017) suggested that the geomagnetic storm impact leads to the decrease

of capillary blood velocity in healthy volunteers from the daytime until the late evening in comparison

with the quiet ambient magnetic conditions. Actually, the same efect of the decrease of capillary blood

velocity had also been observed in patients sufering from myocardial infarction during the period of

the geomagnetic storm (Gurfnkel et al., 1995).

More recently, Pishchalnikov et al. (2019) analyzed the correlation of a daily sequence of interbeat

(RR) intervals combined with measurements of capillary blood velocity in experiments using artifcial

geomagnetic storms. Te results revealed signifcant cardiovascular response specifc to geomagnetic

storms independently from weather conditions (Pishchalnikov et al., 2019). Signifcant correlations of

RR intervals with atmospheric pressure at night time for all modes of MF generation and with tempera­

ture for the Storm mode were found (Pishchalnikov et al., 2019). Te averaged overall subjects’ capillary

blood velocity for all modes appeared not insensitive to geomagnetic storms (Pishchalnikov et al., 2019).

However, the reaction of a few subjects on geomagnetic storm exposure was quite strong and statisti­

cally signifcant. Tere was a hardly noticeable increase in either BP parameter during the Storm regime

(Pishchalnikov et al., 2019). It was suggested that the daily low-frequency (LF) and high-frequency (HF)

dynamics of RR intervals stored as a matrix in time-frequency representation is unique for each subject

and does not depend on the day of the experiment and the weather conditions (Pishchalnikov et al.,

2019). Te averaged correlation coefcients of RR intervals with the Bx and By components appeared

signifcantly higher during the Storm mode in comparison with control (Pishchalnikov et al., 2019).

Tus, it is shown that artifcial geomagnetic storms can cause a detectable cardiovascular response

(Pishchalnikov et al., 2019).