SYMPATHETIC SKIN-RESPONSE ABNORMALITIES IN AMYOTROPHIC-LATERAL-SCLEROSIS

The sympathetic skin response (SSR) was evaluated in 25 patients with amyotrophic lateral sclerosis (ALS) to assess for involvement of the a utonomic nervous system. Twenty-two age-matched normals and 6 patients with muscular dystrophy served as controls. The SSR was intact in all normal volunteers and all patients with muscular dystrophy. The mean SSR latency in the ALS patients was prolonged compared to that of norm als (2.29 +/- 0.28 versus 2.13 +/- 0.16 s, P < 0.05). The SSR was abse nt in one or both legs of 10 ALS patients (40%). Absence or abnormal l atency of SSR in patients with ALS without clinical findings of autono mic failure suggests involvement of the autonomic nervous s stem in ad dition to the motor s tem. (C) 1993 John Wiley & Sons, Inc.