At-home Treatment With Cortico-spinal tDCS for Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is an irreversible neurodegenerative disorder characterized by progressive muscle weakness and atrophy, affecting all skeletal and respiratory muscles. This leads to increasing difficulties in speech, swallowing, and ultimately breathing. A progressive rise in neurofilament light chain (NfL) levels-biomarkers of neuronal damage-has also been documented and may serve as a tool for monitoring disease progression. Average survival ranges from 20 to 48 months. Currently, there is no cure for ALS. Only two drugs, riluzole and edaravone, have demonstrated a modest extension of survival. In this context, transcranial direct current stimulation (tDCS) has emerged as a promising non-invasive neuromodulatory technique capable of modulating central nervous system excitability. Its popularity is growing due to its simplicity, low cost, and broad therapeutic potential across various neurodegenerative conditions. tDCS exerts long-lasting effects on synaptic plasticity in the motor cortex, primarily through modulation of NMDA receptors and GABAergic systems. Given that ALS involves irreversible degeneration of both upper and lower motor neurons in the motor cortex and spinal cord, tDCS may offer therapeutic benefit. Preliminary studies have shown transient improvements in muscle strength and survival following cortico-spinal tDCS administered over two weeks. Building on these findings, a protocol is proposed for home-based tDCS treatment in ALS patients, consisting of multiple sessions aimed at achieving greater and more sustained effects. A brain stimulation device specifically designed for home use will be employed. This device incorporates safety features that monitor for improper usage. The procedure involves applying an anodal stimulation over the motor cortex bilaterally and a cathodal stimulation over the cervical spinal cord. Stimulation sessions will be conducted five days per week over a 16-week period. Home-based tDCS offers a safe alternative to hospital-based treatment, eliminating the need for daily travel and allowing patients to undergo therapy in the comfort of their own homes. This approach represents a potentially significant innovation in ALS care-offering a non-invasive, safe, and accessible therapeutic option that may enhance quality of life and open new avenues for research in neurodegenerative disease management.