Diabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus (DM) that can cause annoying symptoms. To address this condition, several treatment approaches have been proposed, including static magnetic field (SMF) therapy, which has shown promise in treating neurological conditions. Therefore, this study aimed to investigate the effects of SMF therapy on symptomatic DPN and the quality of life (QoL) in patients with type 2 diabetes.
A double-blind, randomized, placebo-controlled trial was conducted from April to October 2021. Sixty-four DPN patients (20 males, 44 females) were recruited for the study via invitation. The participants were divided into two groups: the magnet group, which used magnetic ankle bracelets (155 mT) for 12 weeks, and the sham group, which used non-magnetic ankle bracelets for the same duration. Neuropathy Symptom Score (NSS), Neuropathic Disability Score (NDS), and Visual Analogue Scale (VAS) were used to assess neuropathy symptoms and pain. In addition, the Neuropathy Specific Quality of Life Questionnaire (Neuro-QoL) tool was used to measure the patients’ quality of life.
Before treatment, there were no significant differences between the magnet and sham groups in terms of the NSS scores (P = 0.50), NDS scores (P = 0.74), VAS scores (P = 0.17), and Neuro-QoL scores (P = 0.82). However, after 12 weeks of treatment, the SMF exposure group showed a significant reduction in NSS scores (P < 0.001), NDS scores (P < 0.001), VAS scores (P < 0.001), and Neuro-QoL scores (P < 0.001) compared to the baseline. The changes in the sham group, on the other hand, were not significant.
The authors concluded that according to obtained data, SMF therapy is recommended as an easy-to-use and drug-free method for reducing DPN symptoms and improving QoL in diabetic type-2 patients.
Our own study and systematic review of the effects of magnetic bracelets and similar devices suggested that the effects of such treatments are due to placebo responses. Therefore, I find the findings of this new study most surprising. Not only that, to be honest, I also find them suspect. Apart from the fact that the treatment has no biological plausibility, I have three main reasons for my skepticism.
- The authors stated that there was no distinguishable difference between the sham and SMF devices in terms of their appearance, weight, or texture, which helped to ensure that the study was double-blinded. This is nonsense, I am afraid! The verum device is magnetic and the sham device is not. It is hardly conceivable that patients who handle such devices for any length of time do not discover this simple fact and thus de-blind themselves. In turn, this means that a placebo effect can easily explain the outcomes.
- Authors who feel that their tiny study of a highly implausible therapy lends itself to concluding that their therapy ‘is recommended as an easy-to-use and drug-free method for reducing DPN symptoms and improving QoL’ can, in my view, not be taken seriously.
- Something that always makes me suspicious of clinical trials is a lack of a placebo response where one would normally expect one. In this study, the control group exhibits hardly any placebo response. Wearing a strap around your ankle that allegedly emits therapeutic radiation would result in quite a strong placebo effect, according to our own findings.
So, forgive me if I do not trust this study any further than I can throw it! And pardon me if I still think that our previous conclusion is correct: The evidence does not support the use of static magnets for pain relief, and therefore magnets cannot be recommended as an effective treatment.