title: Assessing autonomic dysfunction in early diabetic neuropathy: the Survey of Autonomic Symptoms.
abstract: OBJECTIVE
  Autonomic symptoms may occur frequently in diabetic and other neuropathies. There is a need to develop a simple instrument to measure autonomic symptoms in subjects with neuropathy and to test the validity of the instrument.
  
  
  METHODS
  The Survey of Autonomic Symptoms (SAS) 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). The SAS was tested in observational studies and compared to a previously validated autonomic scale, the Autonomic Symptom Profile (ASP), and to a series of autonomic tests.
  
  
  RESULTS
  The SAS was tested in 30 healthy controls and 62 subjects with neuropathy and impaired glucose tolerance or newly diagnosed diabetes. An increased SAS score was associated with the previously validated ASP (rank order correlation=0.68; p<0.0001) and with quantitative measures of autonomic function: a reduced quantitative sudomotor axon reflex test sweat volume (0.31; p<0.05) and an abnormal 30:15 ratio (0.53; p<0.01). The SAS shows a high sensitivity and specificity (area under the receiver operating characteristic curve 0.828) that compares favorably with the ASP. The SAS scale domains had a good internal consistency and reliability (Cronbach α=0.76). The SAS symptom score was increased in neuropathy (95% confidence interval [CI] 2.99-4.14) compared to control (95% CI 0.58-1.69; p<0.0001) subjects.
  
  
  CONCLUSIONS
  The SAS is a new, valid, 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.
authors.affiliation: Department of Neurology, University of Maryland and Maryland VA Healthcare System, Baltimore, MD, USA.
authors.forename: L
authors.initials: L
authors.lastname: Zilliox
authors.forename: A C
authors.initials: AC
authors.lastname: Peltier
authors.forename: P A
authors.initials: PA
authors.lastname: Wren
authors.forename: A
authors.initials: A
authors.lastname: Anderson
authors.forename: A G
authors.initials: AG
authors.lastname: Smith
authors.forename: J R
authors.initials: JR
authors.lastname: Singleton
authors.forename: E L
authors.initials: EL
authors.lastname: Feldman
authors.forename: N B
authors.initials: NB
authors.lastname: Alexander
authors.forename: J W
authors.initials: JW
authors.lastname: Russell
mesh_terms: D001342:Autonomic Nervous System Diseases / Q000150:complications / Q000175:diagnosis*; D003929:Diabetic Neuropathies / Q000150:complications / Q000175:diagnosis*; D003943:Diagnostic Techniques, Neurological; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires