title: Autonomic dysfunction in Machado-Joseph disease.
abstract: OBJECTIVE
  Machado-Joseph disease is an autosomal dominant spinocerebellar ataxia with expanded trinucleotide repeats. Although autonomic nervous system degeneration was documented in postmortem reports, the autonomic dysfunction in patients with Machado-Joseph disease, either in clinical analysis or electrophysiological investigations, has not yet been studied in detail.
  
  
  METHODS
  Fifteen patients with genetically confirmed Machado-Joseph disease and 34 healthy subjects were studied. The study design included a detailed questionnaire, R-R interval variation on deep breathing or Valsalva maneuver, and sympathetic skin response evoked by electrical stimulation of the median nerve or magnetic stimulation of the neck.
  
  
  RESULTS
  Sixty-seven percent of patients had at least 3 symptoms involving different aspects of autonomic functions. Voiding problems and thermoregulatory disturbance were the most common symptoms. Ten (71%) of 14 patients had abnormal R-R interval variation with a significant reduction of the mean ratio. Prolonged latency or absence of sympathetic skin response to electrical stimulation was identified in 73% of patients and to magnetic stimulation, in 53%. R-R interval variation and sympathetic skin response showed good correlation with the functional stage. Electrical stimulation revealed the highest sensitivity, specificity, and positive predictive value compared with other tests.
  
  
  CONCLUSIONS
  The present investigation documents that autonomic dysfunction is not uncommon in patients with Machado-Joseph disease and might be related to the clinical progression.
authors.affiliation: First Department of Neurology and Human Molecular Genetic Laboratory, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Tu-Hsueh
authors.initials: TH
authors.lastname: Yeh
authors.forename: Chin-Song
authors.initials: CS
authors.lastname: Lu
authors.forename: Yah-Huei Wu
authors.initials: YH
authors.lastname: Chou
authors.forename: Chok-Chean
authors.initials: CC
authors.lastname: Chong
authors.forename: Tony
authors.initials: T
authors.lastname: Wu
authors.forename: Nai-Hui
authors.initials: NH
authors.lastname: Han
authors.forename: Rou-Shayn
authors.initials: RS
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D001833:Body Temperature Regulation / Q000235:genetics; D003080:Cold Temperature / Q000009:adverse effects; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D017827:Machado-Joseph Disease / Q000150:complications* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D012867:Skin / Q000294:innervation / Q000503:physiopathology; D011795:Surveys and Questionnaires; D017779:Sympathetic Fibers, Postganglionic / Q000503:physiopathology; D001750:Urinary Bladder, Neurogenic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D014661:Vasoconstriction / Q000502:physiology