Sympathetic Skin Response in Amyotrophic Lateral Sclerosis

Area of Science:

• Neurology
• Autonomic Nervous System Function

Background:

• Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease primarily affecting motor neurons.
• ALS is increasingly understood as a systemic disorder beyond motor neuron degeneration.
• Limited research exists on the sympathetic skin response (SSR) in ALS.

Purpose of the Study:

• To investigate the role and characteristics of SSR in patients with sporadic ALS.
• To compare SSR findings in ALS patients with those in healthy controls.

Main Methods:

• A literature review focusing on SSR in ALS.
• Investigated SSR in 120 sporadic ALS patients and 130 age-matched healthy controls.
• Standard SSR testing was performed on all participants.

Main Results:

• ALS patients exhibited prolonged mean SSR latency and reduced mean SSR amplitude compared to controls.
• SSR amplitude reduction was most pronounced in the lower extremities (P < 0.05).
• Disease duration did not significantly impact SSR latency or amplitude (P > 0.05).

Conclusions:

• SSR impairment in ALS predominantly affects the lower extremities.
• This impairment may represent a subclinical manifestation of ALS, preceding clinical autonomic dysfunction.
• Damage to unmyelinated postganglionic fibers is hypothesized as the cause of SSR changes in ALS.