Saravanan Mohanraj1, Krishnamurthy Narayanan2
Diabetes mellitus, a metabolic disorder affects the nervous system due to alteration in various metabolic pathways. As neuropathy manifests in longstanding diabetes mellitus, autonomic nervous system also gets affected. The study was started based on the hypothesis that the sweat glands innervated by autonomic nervous system will be affected in patients with type 2 diabetes mellitus patients with clinical features of neuropathy. This study was undertaken to compare the sympathetic skin response (SSR) and galvanic skin resistance (GSR) in males with type 2 diabetes mellitus and in controls.
Thirty males in the age group of 45-55 years, known to have diabetes mellitus and having a history of neuropathic symptoms served as subjects and thirty males in the same age group with no history of diabetes mellitus and neuropathy served as controls. SSR and GSR were recorded using Recorders and Medicare Systems 4 channel polygraph in the noise and light reduced research laboratory, Department of Physiology. All the recordings were done between 10-12 noon at ambient temperature. SSR was measured by deep inspiration and the GSR was measured in the supine and standing response. Comparison of latency and amplitude of the sympathetic skin response and the percentage of decrease in galvanic skin resistance was done.
A statistically significant delay in the latency and a reduction in the amplitude of sympathetic skin response was observed in the diabetes patients. There was a lesser percentage of decrease in GSR in the diabetic patients.
This study shows that the SSR and GSR responses are significantly reduced in diabetic individuals and can be used as a diagnostic tool in the detection of diabetic autonomic neuropathy.