Waveform of sympathetic skin response in diabetic patients

Abstract

Objective: The aim of this study was to investigate whether there were differences in amplitude and latency among the different waveform patterns of sympathetic skin response (SSR) in diabetic patients. The authors also investigated whether the proportion of the SSR waveform patterns was influenced by diabetic polyneuropathy (DP), symptoms of dysautonomia, and impaired R-R interval variation of the heart rate.Design/methods: Twenty SSRs from palm skin were analyzed in 53 diabetic patients and 45 normal subjects. Waveforms were classified as either the P type, in which the positive component was larger than the negative one, or the N type, in which the negative component was larger than the positive one. The patterns of occurrence in these two waveform types were classified into 3 kinds, i.e. P, N, and M patterns. In the P and N patterns, all the SSRs were of the P and N types, respectively. The M pattern had both P and N types during consecutive recordings.Results: The patients’ age and glycosylated hemoglobin values did not differ among the 3 SSR patterns. The P pattern, however, had a larger amplitude and shorter latency than the N pattern, just as previously reported in a normal population. The distribution of the SSR patterns in diabetic patients was not statistically different from that in the normal controls, and it was not influenced by the DP, symptoms of dysautonomia, or impaired R-R interval variation of the heart rate.Conclusions: The distribution of the SSR waveform patterns was not influenced by the pathological conditions related to diabetes. It might be advised to confirm the balanced distribution of the SSR waveform patterns in patient and control groups before comparing the values of amplitude and latency between the two groups.