title: A comparative study of cardiac dysautonomia in autosomal dominant spinocerebellar ataxias and idiopathic sporadic ataxias.
abstract: OBJECTIVE
  Comparative evaluation of cardiac dysautonomia in spinocerebellar ataxias (SCA) and idiopathic sporadic ataxias (IA) not fulfilling the criteria of multiple system atrophy.
  
  
  METHODS
  Cardiac autonomic functions were evaluated in 14 SCA (SCA1 = 6, SCA2 = 5 and SCA3 = 3) and 10 IA patients, comparable for age, age at onset, duration and severity of illness. The results were categorized as early, definitive, or severe autonomic involvement (EI, DI and SI respectively) based on the degree of abnormalities on tests of parasympathetic and sympathetic pathways.
  
  
  RESULTS
  Cardiac autonomic dysfunction was present in all (EI = 25.0%, DI = 41.7% and SI = 33.3%), parasympathetic dysfunction being an early feature. SI was most often present in SCA3 (100%), followed by those with SCA1 (66.7%), and SCA2 (20%) and none in IA.
  
  
  CONCLUSIONS
  Cardiac dysautonomia was common in both SCA and IA, although the severity was greater in SCA. Among SCAs, the severity was greatest in SCA3, followed by SCA2 and least in SCA1.
authors.affiliation: Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, India.
authors.forename: M
authors.initials: M
authors.lastname: Netravathi
authors.forename: T N
authors.initials: TN
authors.lastname: Sathyaprabha
authors.forename: K
authors.initials: K
authors.lastname: Jayalaxmi
authors.forename: P
authors.initials: P
authors.lastname: Datta
authors.forename: M
authors.initials: M
authors.lastname: Nirmala
authors.forename: P K
authors.initials: PK
authors.lastname: Pal
mesh_terms: D000293:Adolescent; D000328:Adult; D001259:Ataxia / Q000150:complications* / Q000235:genetics; D001342:Autonomic Nervous System Diseases / Q000150:complications*; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000150:complications*; D006801:Humans; D008297:Male; D012720:Severity of Illness Index; D055815:Young Adult