Limits of the sympathetic skin response in patients with diabetic polyneuropathy

We performed upper- and lower-limb sympathetic skin responses (SSRs) in a series of 337 diabetic patients with and without peripheral polyneuropathy and 38 reference subjects. We did not find any correlations between SSRs and symptoms of pain or autonomic dysfunction. The SSR correlated more strongly with vibration perception threshold (VPT) and sural nerve amplitude than with cooling detection threshold (CDT) or clinical symptoms. We conclude that current limitations inherent in SSR testing preclude its use as a reliable and consistent index of the autonomic dysfunction commonly encountered in diabetic patients.