Repetitive transcranial magnetic stimulation (rTMS) for treating amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), is a fatal neurodegenerative disease without significant therapy. People living with this disease become progressively paralysed due to degeneration of the upper and lower motor neurons in the brain and spinal cord. Repetitive transcranial magnetic stimulation (rTMS) has been introduced as a neurophysiological technique and found to have therapeutic activity in several controlled studies on patients with ALS. It is a non-invasive way of stimulating nerve cells in superficial areas of the brain. The technique works through administering pulsed magnetic fields to the surface of the brain at variable frequencies. In this review we identified three studies involving in total 50 participants with ALS. None of the studies reported on the primary outcome, which was disability or limitation in activity as assessed by the ALS Functional Rating Scale-Revised (ALSRFS-R) at six months follow-up. Detailed data on secondary outcomes were only available from 12 participants in one poor quality trial, in which there was no difference between rTMS and sham rTMS in ALSRFS-R or manual muscle testing scores at 12 months follow up. However, rTMS was generally well tolerated by the patients with ALS according to the three included studies; none reported any adverse events associated with the use of rTMS. Considering the small number of patients examined, the flaws in the methods of the three studies and incomplete outcome data, further trials with large sample size and adequate methodology should be considered to determine the efficacy and safety of rTMS in the treatment of ALS, if their potential benefit is weighed against the impact of participation in trials on people with ALS.