Efficacy of Repetitive Trans-spinal Magnetic Stimulation for Patients with Parkinson's Disease: a Randomised Controlled Trial

Electromagnetic fields regulate iron metabolism: From mechanisms to applications

BACKGROUND

Electromagnetic fields (EMFs), as a form of physical therapy, have been widely applied in biomedicine. Iron, the most abundant trace metal in living organisms, plays a critical role in various physiological processes, and imbalances in its metabolism are closely associated with the development and progression of numerous diseases. Numerous studies have demonstrated that EMF exposureinduces significant changes in both systemic and cellular iron metabolism.

AIM OF REVIEW

This review aims to summarize the evidence and potential biophysical mechanisms underlying the role of EMFs in regulating iron metabolism, thereby enhancing the understanding of their biological mechanisms and expanding their potential applications in biomedical fields.

KEY SCIENTIFIC CONCEPTS OF REVIEW

In this review, we have synthesized research findings and proposed the hypothesis that the biophysical mechanisms of EMFs regulate iron metabolism involve the special electromagnetic properties of iron-containing proteins and iron-enriched tissues, as well as the modulation of membrane structure and function, ion channels, and the generation and activity of Reactive Oxygen Species (ROS). Then, the review summarizes the latest advances in the effects of EMFs on iron metabolism and their safety, as well as their impact on immunoregulation, cardiovascular diseases, neurological diseases, orthopedic diseases, diabetes, liver injury, and cancer.

In PD, Non-Invasive Trans-Spinal Magnetic Stimulation Enhances the Effect of Transcranial Magnetic Stimulation on Axial Motor Symptoms: A Double-Blind Randomized Clinical Trial

BACKGROUND

Axial symptoms in Parkinson's disease (PD) often respond poorly to pharmacological treatment. We evaluated whether combining repetitive transcranial magnetic stimulation (rTMS) and repetitive spinal magnetic stimulation (rSMS) is more effective than rTMS alone in improving axial and other motor disabilities in PD.

METHODS

A total of 42 PD patients with axial symptoms were randomly allocated to 2 experimental intervention groups: Group I received active rTMS + active rSMS (2000 pulses; 20 Hz; 80% resting motor threshold for each motor area "M1" + 1500 pulses rSMS 10 Hz, at 50% of maximal stimulator output). Group II received active rTMS + sham rSMS with the same number of pulses. Both groups received 10 sessions (5 consecutive days/week for 2 weeks). Assessments using Freezing of Gait Questionnaire, walking speed, Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) parts II and III, and Parkinson's Disease Questionaire-39 (PDQ-39) were performed at baseline (T0), end of sessions (T1), and 1 month later (T2).

RESULTS

At T0, Group II showed higher walking speed. At T1 and T2, Group I demonstrated significantly greater improvements in MDS-UPDRS parts II, III, and sub-items of part III. Group I showed stronger improvement in TUG-T and average fast velocity immediately post-intervention, but this effect diminished after 1 month. PDQ-39 scores for leisure activity and walking problems were significantly higher in group I.

CONCLUSIONS

These findings indicate that combining rTMS and rSMS for 10 sessions is more effective than rTMS alone in managing PD's motor and axial symptoms. The effect size of the outcome is large enough to be of significance in clinical practice.

TRIAL REGISTRATION

The study was registered prospectively on 26/12/2021 at the clinicaltrial.gov website with the registration ID: NCT05271513, https://clinicaltrials.gov/study/NCT05271513.

Efficacy of repetitive transcranial magnetic stimulation combined with peripheral magnetic stimulation on movement symptom and exploration of the optimal population in Parkinson's disease: A randomized controlled trial

BACKGROUND

This study explores the efficacy of repetitive transcranial magnetic stimulation (rTMS) and rTMS combined with repetitive peripheral magnetic stimulation (rPMS) (hereinafter referred to as rTMS + rPMS) on motor symptoms and quality of life in Parkinson's disease (PD), and explores whether there are differences between the two treatment methods; At the same time, analyze data from different subgroups to explore the influencing factors, in order to find the most suitable treatment group.

METHODS

Eighty patients with PD were randomly divided into rTMS and rTMS + rPMS groups and administered 10 Hz rTMS, and 10 Hz rTMS + 25 Hz rPMS, respectively, for 10 days. Before and after treatment, the PD Motor Function Rating Scale (UPDRS Part III, 10m Walk Timing Test, Stand Up Walk Test Evaluation Scale (TUG)) and PD Quality of Life Questionnaire (PDQ-39) were used to evaluate the motor symptoms and quality of life. After quantifying the treatment effect, a comparative analysis of the efficacy before and after treatment was conducted. Simultaneously, we divided the two treatment groups into different subgroups, compared the subgroups under the same treatment method, analyzed the relevant factors affecting the treatment method, and found the most suitable treatment group.

RESULTS

(1) After rTMS or rTMS + rPMS, all scoring scales improved compared to those before treatment (P < .05). Compared to rTMS, rTMS + rPMS resulted in greater improvements in overall motor function (UPDRS III) and quality of life (PDQ-39) (P < .05). (2) Patients with rigidity-based type as the main type may be the most suitable for these two treatment methods (P < .05).(3) There was no significant difference in treatment efficiency between the two treatment methods for patients with PD at different disease stages, sexes, or treatment ages(P > .05).

CONCLUSION

Both rTMS and rTMS + rPMS can improve movement symptoms and quality of life in patients with PD. rTMS + rPMS was more beneficial for improving the overall motor function. Patients with rigidity-based type as the main type may be the most suitable for these two treatment methods. The therapies work in all age groups, all gender and irrespective of the disease stage with varying levodopa equivalent daily doses as well.

Trans-Spinal Theta Burst Magnetic Stimulation in Parkinson's Disease and Gait Disorders

BACKGROUND

Gait disorders in patients with Parkinson's disease (PD) can become disabling with disease progression without effective treatment.

OBJECTIVES

To investigate the efficacy of intermittent θ burst trans-spinal magnetic stimulation (TsMS) in PD patients with gait and balance disorders.

METHODS

This was a randomized, parallel, double-blind, controlled trial. Active or sham TsMS was applied at third thoracic vertebra with 100% of the trans-spinal motor threshold, during 5 consecutive days. Participants were evaluated at baseline, immediately after last session, 1 and 4 weeks after last session. Primary outcome was Total Timed Up and Go (TUG) values comparing active versus sham phases 1 week after intervention. The secondary outcome measurements consisted of motor, gait and balance scales, and questionnaires for quality of life and cognition.

RESULTS

Thirty-three patients were included, average age 68.5 (6.4) years in active group and 70.3 (6.3) years in sham group. In active group, Total TUG mean baseline was 107.18 (95% CI, 52.1-116.1), and 1 week after stimulation was 93.0 (95% CI, 50.7-135.3); sham group, Total TUG mean baseline was 101.2 (95% CI, 47.1-155.3) and 1 week after stimulation 75.2 (95% CI 34.0-116.4), P = 0.54. Similarly, intervention had no significant effects on secondary outcome measurements. During stimulation period, five patients presented with mild side effects (three in active group and two in sham group).

DISCUSSION

TsMS did not significantly improve gait or balance analysis in patients with PD and gait disorders. The protocol was safe and well tolerated. © 2024 International Parkinson and Movement Disorder Society.

Different Effect Sizes of Motor Skill Training Combined with Repetitive Transcranial versus Trans-Spinal Magnetic Stimulation in Healthy Subjects

Repetitive transcranial magnetic stimulation (rTMS) is used to enhance motor training (MT) performance. The use of rTMS is limited under certain conditions, such as after a stroke with severe damage to the corticospinal tract. This raises the question as to whether repetitive trans-spinal magnetic stimulation (rSMS) can also be used to improve MT. A direct comparison of the effect size between rTMS and rSMS on the same MT is still lacking. Before conducting the study in patients, we determined the effect sizes of different stimulation approaches combined with the same motor training in healthy subjects. Two experiments (E1 and E2) with 96 subjects investigated the effect size of combining magnetic stimulation with the same MT. In E1, high-frequency rTMS, rSMS, and spinal sham stimulation (sham-spinal) were applied once in combination with MT, while one group only received the same MT (without stimulation). In E2, rTMS, rSMS, and sham-spinal were applied in combination with MT over several days. In all subjects, motor tests and motor-evoked potentials were evaluated before and after the intervention period. rTMS had the greatest effect on MT, followed by rSMS and then sham-spinal. Daily stimulation resulted in additional training gains. This study suggests that rSMS increases excitability and also enhances MT performance. This current study provides a basis for further research to discover whether patients who cannot be treated effectively with rTMS would benefit from rSMS.

Controversies and Clinical Applications of Non-Invasive Transspinal Magnetic Stimulation: A Critical Review and Exploratory Trial in Hereditary Spastic Paraplegia

Magnetic stimulation is a safe, non-invasive diagnostic tool and promising treatment strategy for neurological and psychiatric disorders. Although most studies address transcranial magnetic stimulation, transspinal magnetic stimulation (TsMS) has received recent attention since trials involving invasive spinal cord stimulation showed encouraging results for pain, spasticity, and Parkinson’s disease. While the effects of TsMS on spinal roots is well understood, its mechanism of action on the spinal cord is still controversial. Despite unclear mechanisms of action, clinical benefits of TsMS have been reported, including improvements in scales of spasticity, hyperreflexia, and bladder and bowel symptoms, and even supraspinal gait disorders such as freezing and camptocormia. In the present study, a critical review on the application of TsMS in neurology was conducted, along with an exploratory trial involving TsMS in three patients with hereditary spastic paraplegia. The goal was to understand the mechanism of action of TsMS through H-reflex measurement at the unstimulated lumbosacral level. Although limited by studies with a small sample size and a low to moderate effect size, TsMS is safe and tolerable and presents consistent clinical and neurophysiological benefits that support its use in clinical practice.