Usefulness of the survey of autonomic symptoms questionnaire in diagnosis of diabetic autonomic neuropathy

Abstract

Background: Diabetic autonomic neuropathy is a serious and common complication of diabetes. There is a need to develop a simple instrument to measure autonomic symptoms in patients with neuropathy and to test the validity of the instrument. Using the survey of autonomic symptoms (SAS) questionnaire for screening diabetic autonomic neuropathy is a new procedure. Sympathetic skin response (SSR) is a method for the study of autonomic nervous system. Given the importance of diabetes and its autonomic complications, in this study, data obtained from the SAS questionnaire was compared with the SSR to know whether it can be used for these patients. Methods: In this cross-sectional study, the patients with a diagnosis of diabetes with at least one symptom of autonomic dysfunction, referred to the clinic of Neurology and Clinical Endocrinology, after obtaining written informed consent were enrolled. For each patient, the SAS questionnaire was completed and SSR was assessed via electromyography (EMG) recording. The SAS questionnaire consists of 11 items in women and 12 in men. Each item is rated by an impact score ranging from 1 (least severe) to 5 (most severe). Findings: The SAS was tested in 135 patients with neuropathy and diabetes. The mean score of SAS was 16.82 ± 12.62, that was not significantly related to age and gender. 60 patients (44.4) had positive and 75 patients (55.6) had a negative SSR response. Independent t-test showed a significant association between the response of SSR and the score of SAS (P < 0.001). In receiver operating characteristic curve (ROC curve) analysis, the numeric value of the SAS score equal to 9.5 with a sensitivity of 88 and specificity of 70 was obtained as a cut-point for SSR response. Conclusion: The SAS is a new, valid, and easily administered instrument to measure autonomic symptoms in early diabetic neuropathy and would be of value in assessing neuropathic autonomic symptoms in clinical trials and epidemiologic studies. © 2016, Isfahan University of Medical Sciences(IUMS). All rights reserved.