title: The natural progression of autonomic neuropathy and autonomic function tests in a cohort of people with IDDM.
abstract: OBJECTIVE
  To test the natural progression of symptoms of autonomic neuropathy (AN) and function tests in subjects with IDDM.
  
  
  METHODS
  Seventy-six subjects with IDDM of < 10 years duration had cardiovascular autonomic reflex tests and were evaluated for signs and symptoms of AN.
  
  
  RESULTS
  Fifty-seven subjects (66%) were available for restudy 9 years later (15 had died, 4 could not be located). Of the symptoms of AN, only gastroparesis increased in prevalence (P < 0.01). Of the five cardiovascular AN measures, only the R-R response to the Valsalva maneuver deteriorated (F[1,44] = 10.61, P < 0.01).
  
  
  CONCLUSIONS
  The progression of AN in IDDM is monitored best longitudinally by the Valsalva maneuver because of the small variance ratio in repeated measures. Prevalence rates can be monitored by expiration-to-inspiration R-R or Valsalva ratios. Most clinical signs and symptoms of AN do not progress, underscoring the need for objective and quantitative autonomic function tests to identify people at risk for premature death.
authors.affiliation: University of Cape Town, Groote Schuur Hospital, South Africa.
authors.forename: N S
authors.initials: NS
authors.lastname: Levitt
authors.forename: K B
authors.initials: KB
authors.lastname: Stansberry
authors.forename: S
authors.initials: S
authors.lastname: Wynchank
authors.forename: A I
authors.initials: AI
authors.lastname: Vinik
mesh_terms: D000293:Adolescent; D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology; D001342:Autonomic Nervous System Diseases / Q000503:physiopathology*; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications* / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000502:physiology; D006801:Humans; D008297:Male