Sympathetic skin response abnormalities in amyotrophic lateral sclerosis

Area of Science:

• Neurology
• Autonomic Neuroscience

Background:

• Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease primarily affecting motor neurons.
• Autonomic nervous system (ANS) dysfunction is increasingly recognized in ALS, but its extent requires further elucidation.

Purpose of the Study:

• To investigate the involvement of the autonomic nervous system in ALS patients using sympathetic skin response (SSR) testing.
• To compare SSR parameters between ALS patients, healthy controls, and muscular dystrophy patients.

Main Methods:

• Sympathetic skin response (SSR) was measured in 25 ALS patients, 22 age-matched healthy controls, and 6 muscular dystrophy patients.
• SSR latency and presence were analyzed and compared across the groups.

Main Results:

• SSR was intact in all healthy controls and muscular dystrophy patients.
• ALS patients exhibited significantly prolonged mean SSR latency compared to controls (2.29 ± 0.28 s vs. 2.13 ± 0.16 s, P < 0.05).
• SSR was absent in 40% of ALS patients (10 out of 25), indicating significant autonomic dysfunction.

Conclusions:

• The study demonstrates significant sympathetic skin response abnormalities in ALS patients.
• These findings suggest subclinical autonomic nervous system involvement in ALS, even in the absence of overt autonomic failure symptoms.
• SSR testing is a valuable tool for assessing ANS function in ALS and understanding the disease's complex pathophysiology.