Pulsed Electromagnetic Field Therapy (PEMF or PEMT) is a non-invasive, painless treatment which works by emitting a pulsating, varying intensity and frequency electromagnetic field, coming from a solenoid placed around the patient. Pulsed electromagnetic field therapy was approved by the FDA in 1979 specifically for the healing of nonunion fractures, which came after a Columbia University study that was encouraged by NASA, and has recently gained attention in the U.S (even appearing as a segment on the Dr. Oz Show). The value of pulsed electromagnetic field therapy has been shown to cover a wide range of conditions, with well documented trials carried out by hospitals, rheumatologists, physiotherapists, and neurologists. PEMF was widely used and with great success in the 19th and early 20th century. These primitive electromagnetic therapeutic devices were used by both medical doctors and non-allopathic health practitioners.
The research to date has shown that the mechanisms by which PEMF works are complicated and likely involve many pathways. In addition to increasing cell metabolism, perhaps PEMF’s greatest power is in its ability to ameliorate the effects of inflammation by decreasing inflammatory cytokines. it is also conceivable, as suggested by Gordon et al, that another important effect of PEMF is the ability of the magnetic fields to restore “equilibrium in ROS (free radical)/antioxidant chemistry. It is unequivocal that all chronic diseases result from a lack of homeostasis between free radicals and antioxidants. While both free radicals and antioxidants are normal and vital for processes such as cellular respiration and immunity, an imbalance could lead to cell and tissue death, DNA damage, and protein and fat degradation.
Pulsed Electromagnetic Field Therapy and Parkinson’s Disease
Magnetic therapy for Parkinson’s is nearly exclusively done in form of repetitive transcranial magnetic stimulation (rTMS). rTMS is in fact PEMF simply applied to the head and called repetitive transcranial magnetic stimulation.
A systematic review aimed to examine the efficacy of rTMS on improving physical function and motor signs over the short- and long-terms in people with PD; Effect of Repetitive Transcranial Magnetic Stimulation on Physical Function and Motor Signs in Parkinson's Disease: A Systematic Review and Meta-Analysis; Chung CL; Brain Stimul. 2016 Jul-Aug;9(4):475-87. Twenty-two trials comprising 555 people with PD were included in the review. The pooled evidence suggests that rTMS improves upper limb function in the short-term, walking performance and Unified Parkinson’s Disease rating Scale (UPDRS III) in the short- and long-terms in PD sufferers.
Pulsed Electromagnetic Field Therapy and Chronic Pain
A randomized, double-blind, placebo-controlled clinical trial using a low-frequency magnetic field in the treatment of musculoskeletal chronic pain; Alex W Thomas, PhD; Pain Res Manag. 2007 Winter; 12(4): 249–258.
Exposure to a specific pulsed electromagnetic field (PEMF) has been shown to produce analgesic (antinociceptive) effects in many organisms. In a randomized, double-blind, sham-controlled clinical trial, patients with either chronic generalized pain from fibromyalgia (FM) or chronic localized musculoskeletal or inflammatory pain were exposed to a PEMF (400 μT) through a portable device fitted to their head during twice-daily 40 min treatments over seven days. The effect of this PEMF on pain reduction was recorded using a visual analogue scale. A differential effect of PEMF over sham treatment was noticed in patients with FM, which approached statistical significance (P=0.06) despite low numbers (n=17); this effect was not evident in those without FM (P=0.93; n=15). PEMF may be a novel, safe and effective therapeutic tool for use in at least certain subsets of patients with chronic, nonmalignant pain.
An open-label pilot study of pulsed electromagnetic field therapy in the treatment of failed back surgery syndrome pain; Wayne L Harper; Int Med Case Rep J. 2015; 8: 13–22 The primary objective of this open-label exploratory study was to investigate the analgesic effectiveness of pulsed electromagnetic field therapy administered twice daily over a 45-day period in 34 subjects (68% female) with persistent or recurrent pain following back surgery. Of the 30 per-protocol subjects who completed the study, 33% reported a clinically meaningful (≥30%) reduction in pain intensity (PI). A higher response rate (60%) was reported for subjects who had undergone discectomy prior to the trial compared to subjects who had undergone other types of surgical interventions (decompression or fusion) without discectomy. Improvements in PI were paralleled by improvements in secondary outcomes. Relative to baseline, responders reported an average 44% and 55% reduction in back PI and leg PI (respectively), and an average 13% improvement in Oswestry Disability Index scores. In the per-protocol population, 50% of responders and 12% of non-responders reported less analgesia consumption at the end of treatment versus baseline. Sixty-seven percent of per-protocol responders and 0% of non-responders reported clinically meaningful improvement in overall well-being on the Patient Global Impression of Change scale.
Pulsed Electromagnetic Field Therapy and Multiple Sclerosis
Effects of a pulsed electromagnetic therapy on multiple sclerosis fatigue and quality of life: a double-blind, placebo controlled trial; Lappin MS; Altern Ther Health Med. 2003 Jul-Aug;9(4):38-48. This study is a follow-up to a placebo controlled pilot study in which multiple sclerosis (MS) patients exposed to weak, extremely low frequency pulsed electromagnetic fields showed significant improvements on a composite symptom measure. This study was a multi-site, double-blind, placebo controlled, crossover trial involving 117 patients with MS. Each subject received 4 weeks of the active and placebo treatments separated by a 2-week washout period. Paired t-tests were used to assess treatment differences in the 117 subjects (81% of the initial sample) who completed both treatment sessions. Improvements in fatigue and overall quality of life were significantly greater on the active device.
Pulsed Electromagnetic Field Therapy and Dementia
Cognitive functioning after repetitive transcranial magnetic stimulation in patients with cerebrovascular disease without dementia: a pilot study of seven patients; Rektorova; J Neurol Sci. 2005 Mar 15;229-230:157-61 This study aimed to examine whether one session of high frequency repetitive transcranial magnetic stimulation (rTMS) applied over the left dorsolateral prefrontal cortex (DLPFC) would induce any measurable cognitive changes in patients with cerebrovascular disease and mild cognitive deficits. Seven patients with cerebrovascular disease and mild executive dysfunction entered the randomized, controlled, blinded study with a crossover design. rTMS was applied either over the left DLPFC (an active stimulation site) or over the left motor cortex (MC; a control stimulation site) in one session. Each patient participated in both stimulation sessions (days 1 and 4) and the order of stimulation sites (DLPFC or MC) was randomized. A short battery of neuropsychological tests was performed by a blinded psychologist prior to and after each rTMS session. Psychomotor speed, executive function, and memory were evaluated. Results: mild but significant stimulation site-specific effect of rTMS was observed in the Stroop interference results (i.e. improvement) after the stimulation of DLPFC in comparison with the baseline scores (Wilcoxon, Z=-2.03, p=0.04). Patients improved in the digit symbols subtest of the Wechsler adult intelligence scale-revised after both rTMS sessions regardless of the stimulation site.
Alzheimer’s disease: improvement of visual memory and visuoconstructive performance by treatment with picotesla range magnetic fields; Sandyk R; Int J Neurosci. 1994 Jun;76(3-4):185-225. The author had previously reported that external application of electromagnetic fields (EMF) of extremely low intensity (in the picotesla range) and of low frequency (in the range of 5Hz-8Hz) improved visual memory and visuoperceptive functions in patients with Parkinson's disease. Since a subgroup of Parkinsonian patients, specifically those with dementia, have coexisting pathological and clinical features of AD, the author investigated in two AD patients the effects of these extremely weak EMF on visual memory and visuoconstructive performance. The Rey-Osterrieth Complex Figure Test as well as sequential drawings from memory of a house, a bicycle, and a man were employed to evaluate the effects of EMF on visual memory and visuoconstructive functions, respectively. In both patients treatment with EMF resulted in a dramatic improvement in visual memory and enhancement of visuoconstructive performance which was associated clinically with improvement in other cognitive functions such as short term memory, calculations, spatial orientation, judgement and reasoning as well as level of energy, social interactions, and mood. The report demonstrates, for the first time, that specific cognitive symptoms of AD are improved by treatment with EMF of a specific intensity and frequency. The rapid improvement in cognitive functions in response to EMF suggests that some of the mental deficits of AD are reversible being caused by a functional (i.e., synaptic transmission) rather than a structural (i.e., neuritic plaques) disruption of neuronal communication in the central nervous system.
Pulsed Electromagnetic Field Therapy in Cancer
Several mechanisms of PEMF therapy have been elucidated with regards to cancer. These studies have shown that PEMF therapy may exert proliferative inhibition and mitotic spindle disruption, block the development of neovascularization (blood supply) required for tumor growth and exacerbate an inherent or induced genetic instability by reducing the stringency of the late-cycle (G2) checkpoint. PEMF therapy also modulates gene expression and protein synthesis, interacting with specific DNA sequences within gene promoter regions. PEMFs have also an immunomodulatory effect, as supported by in vivo evidence showing an increase in tumor necrosis factor alpha levels that induce an anti-tumoral response.
Changes in blood pressure, skin electrical resistance, and pulse amplitude in 163 oncology patients exposed to tumor-specific PEMF frequencies have also been reported suggesting that PEMF therapy does not only target neoplastic cells, but may also have systemic effects. However, long-term PEMF treatment has been shown to be non-toxic, and employs 100,000 times lower frequencies as compared with radiofrequency ablation that is also employed for treatment of many cancers.
While chemotherapy is not specific to cancer cells and targets all rapidly dividing cells, PEMFs exert selective cytotoxic effect on neoplastic cells making this therapy a highly promising strategy.
In Vivo Studies
Several studies investigated the antineoplastic effect of PEMFs using widely employed animal models of several types of cancer, including breast cancer, hepatocellular carcinoma (HCC), and melanoma.
PEMF therapy effectiveness in mouse models of breast cancer; Mice were divided into four groups (n = 3 each). Group 1, 2, and 3 were exposed to PEMF therapy (1 Hz, 100 mT) daily for 60, 180, or 360 min, respectively, for 4 weeks, while group 4 did not receive PEMF therapy and was used as control. All mice were monitored for tumor growth by body bioluminescence imaging once every 2 to 4 days for 4 weeks. Then, all the mice were sacrificed and skin, liver, lung, and spleen samples were collected for histopathologic analysis. Mice exposed to PEMFs for 60 and 180 min daily showed a 30% and 70% breast tumor reduction, respectively, at week 4. Mice exposed to PEMF for 360 min daily, showed a suppression of tumor growth at week 4. In summary, this study shows that the time of PEMF exposure is critical to determine its effectiveness. Mice exposed for longer duration (360 min daily for 4 weeks) showed a significant reduction in tumor size, due probably to the inhibition of angiogenesis that may suppress the formation of blood vessels in tumor tissues, reducing the tumor growth.
Human Clinical Studies
The first study utilizing PEMF therapy was conducted by Barbault and coworkers who hypothesized that a combination of defined tumor-specific frequencies, may display therapeutic effectiveness for localized treatment of tumors. They identified a total of 1524 tumor-specific frequencies, ranging from 0.1 to 114 kHz, consisting in the measurement of variations in skin electrical resistance, pulse amplitude, and blood pressure in 163 patients affected by different types of cancer including brain tumors, colorectal cancer, hepatocellular carcinoma, pancreatic, colorectal, ovarian, breast, prostate, lung, thyroid, and bladder cancer and exposed to the radiofrequency system.
Self-administered PEMF therapy for 60 min, three times a day, for an average of 278.4 months was offered to only 28 patients with advanced cancer: 7 breast cancer, 5 ovarian cancer, 3 pancreatic cancer, 2 colorectal cancer, 2 prostate cancer, 1 glioblastoma multiforme, 1 hepatocellular carcinoma, 1 mesothelioma, 1 neuroendocrine tumor, 1 non-small-cell lung cancer, 1 oligodendroglioma, 1 small-cell lung cancer, 1 sarcoma, and 1 thyroid tumor. None of the patients who received PEMF therapy reported any side effects; four patients presented stable disease for 3 years (thyroid cancer with biopsy-proven lung metastases), 6 months (mesothelioma metastatic to the abdomen), 5 months (non-small-cell lung cancer), and 4 months (pancreatic cancer with biopsy-proven liver metastases), respectively.
The feasibility of PEMF therapy for treatment of hepatocellular carcinoma (HCC) has also been investigated in a single-group, open-label, phase I/II clinical study. Forty-one patients with advanced HCC received very low levels of PEMFs modulated at HCC-specific frequencies (100 Hz–21 kHz) and received three-daily 60 min outpatient treatments. No adverse reactions were observed during PEMF treatment. Five patients reported complete disappearance and two patients reported decrease in pain shortly after beginning of treatment. Four patients showed a partial response to treatment, while 16 patients (39%) had stable disease for more than 12 weeks. This study shows that PEMF therapy provides a safe and well-tolerated treatment, as well as evidence of antineoplastic effects in patients with HCC.
PEMF therapy is more commonly used in Europe to treat many ailments, including cancer. Although only two clinical studies have used PEMF therapy for cancer treatment, these studies show that PEMF therapy is safe and promising compared to other available cancer therapies. PEMFs could be used not only as primary therapy but also in combination with other common antineoplastic therapies. Given that new portable and affordable PEMF devices are increasingly available on the market, future controlled clinical studies are expected to further determine the potential of PEMF therapy in conventional oncology.