Köteles F, Szemerszky R, Gubányi M et al. Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) and electrosensibility (ES) - are they connected? Int J Hyg Environ Health. 2013; 216(3):362-70. PMID: 22698789
This study examined the emerging phenomenon of idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF), or the tendency to experience "unpleasant symptoms in the proximity of working electric devices," which the authors state has no clear or conclusive psychophysiological mechanism.
In the study, 29 self-reported IEI-EMF sufferers and 42 control subjects completed symptom and health anxiety questionnaires. The subjects were then asked to try and detect a 50 Hz 0.5 mT magnetic field (MF) directed to their right arm in 20 subsequent 1-minute sessions. During the test, heart rate and heart rate variability indices were measured (high frequency [HF], low-to-high frequency ratio [HF/LF], and the standard deviation of beat-to-beat intervals [SDNN]).
Individuals with IEI-EMF had a statistically significantly higher rate of signal detection compared to controls. Before correctly detecting the MF or its absence, the IEI-EMF subjects showed higher HRV (HF and SDNN measures); no increases in HRV were seen before incorrect detections. The IEI-EMF group also showed close association between symptoms reported on pre-test questionnaires and reported symptoms following exposure.
This study provides some evidence that those reporting IEI-EMF may be able to detect MF, due to heightened sensitivity. While detection of MF may be real, symptoms due to exposure appeared to be psychogenic in origin.
I have a long-time interest in treating allergies and in learning about the emerging field of psychoneuroimmunology. I first became interested in less-understood sensitivities (i.e. MCS, EMF intolerance), and related conditions during the environmental medicine series of BU classes last year. I preceptored with Dr. Rea, MD, in Dallas at the Environmental Health Center. There, I first understood MCS and related illnesses. I also saw Dr. Rea using HRV as a measure of the severity of his patients' autonomic disturbance due to toxic or EMF exposures. As I have seen little evidence of EMF sensitivity in blinded, controlled studies, but several very anxious EMF-sensitive patients, I wanted to see a study on the EMF-HRV connection.
In this study, the authors admit that those who report EMF sensitivity do, indeed, have a greater ability to detect these fields than a group of control subjects. They stop short of attributing these patients' symptoms to the MF, calling them "psychogenic." Here I find the logic breaks down and the article falls short of a more cogent conclusion.
What distinguishes a psychogenic symptom from a "real" one? If the patients are experiencing changes in HRV, that seems like something that could bring about arousal, change nervous system tone, and affect the vagus nerve, evoking symptoms (especially since pre-ganglionic sympathetic fibers from the nucleus ambiguus travel with the vagus nerve and intertwine with it at the ganglion nodosum and superior cardiac nerve). Shifts in nervous system tone could easily cause an already-sensitive patient to be troubled by bodily sensations that the average person doesn't find bothersome.
In my training, I have been taught to recognize that there are some patients who are hyper-sensitive to their outer and/or inner worlds. Hyper-awareness of body sensations contributes to IBS, anxiety/panic disorders, OCD, hypochondriasis, and various pain syndromes. These aren't necessarily psychosomatic--some of us are "wired" differently, and some of us also have poor parasympathetic tone. As Dr. Rea quipped, "when a doctor calls your symptoms psychosomatic, he doesn't know his anatomy."
Explanation of HRV:
Heart rate variability is another type of vital sign (like pulse, breathing rate, or temperature) that we can measure using the special equipment connected to this computer program. The sensors are measuring the amount of time between each heartbeat. What it shows us is the heart's ability to adapt and respond to things like stress and emotions. This program can also tell us about the balance between the two sides of your nervous system--the "flight or fight" side and the "rest and digest" side.