title: A study of up to 12 years of follow-up of Friedreich ataxia utilising four measurement tools.
abstract: OBJECTIVE
  To explore the progression of Friedreich ataxia by analysing the change in scores of four clinical measures (the Friedreich Ataxia Rating Scale (FARS), the International Cooperative Ataxia Rating Scale (ICARS), the Functional Independence Measure (FIM) and the Modified Barthel Index (MBI)) over a period of up to 12 years, to ascertain the effects of clinical variables on performance of these measures, and to determine the most sensitive rating scale for measuring disease progression.
  
  
  METHODS
  We measured the disease progression of up to 147 individuals against disease duration grouped into 5-year intervals. Additional subgroups were created to study the effects of the size of the smaller FXN intron 1 GAA repeat size (GAA1) and onset age on rating scale performance.
  
  
  RESULTS
  Both the FARS and ICARS demonstrated greater change in the first 20 years post disease onset than in the subsequent 20 years during which there was little change in the mean score. While the FIM and MBI continued to deteriorate beyond 20 years post disease onset, floor effects were noted. As measured by the FARS, individuals with a larger GAA1 repeat were found to progress more quickly in the first 20 years of disease.
  
  
  CONCLUSIONS
  Individuals with larger GAA1 repeat sizes and earlier ages of disease onset were shown to deteriorate at a faster rate and were associated with greater FARS and ICARS scores and lower FIM and MBI scores, which are indicative of greater disease severity.
authors.affiliation: Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Victoria, Australia.
authors.forename: Geneieve
authors.initials: G
authors.lastname: Tai
authors.affiliation: Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Victoria, Australia Monash Health, Clayton, Victoria, Australia.
authors.forename: Louise A
authors.initials: LA
authors.lastname: Corben
authors.affiliation: Department of Molecular, Environmental, Genetic and Analytic Epidemiology, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Lyle
authors.initials: L
authors.lastname: Gurrin
authors.affiliation: Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Victoria, Australia Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia Children's Neuroscience Centre, Royal Children's Hospital, Parkville, Victoria, Australia.
authors.forename: Eppie M
authors.initials: EM
authors.lastname: Yiu
authors.affiliation: Monash Health, Clayton, Victoria, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Churchyard
authors.affiliation: Department of Paediatrics, Monash University, Clayton, Victoria, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Fahey
authors.affiliation: Monash Health, Clayton, Victoria, Australia.
authors.forename: Brian
authors.initials: B
authors.lastname: Hoare
authors.affiliation: Monash Health, Clayton, Victoria, Australia.
authors.forename: Sharon
authors.initials: S
authors.lastname: Downie
authors.affiliation: Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Victoria, Australia Monash Health, Clayton, Victoria, Australia Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia Department of Paediatrics, Monash University, Clayton, Victoria, Australia Department of Clinical Genetics, Austin Health, Heidelberg, Victoria, Australia.
authors.forename: Martin B
authors.initials: MB
authors.lastname: Delatycki
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D002648:Child; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005621:Friedreich Ataxia / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D033862:Iron-Binding Proteins / Q000235:genetics; D008297:Male; D008875:Middle Aged; D012091:Repetitive Sequences, Nucleic Acid; D055815:Young Adult; D000520:alpha-Glucosidases / Q000235:genetics; D000096923:Frataxin
chemical_list: D033862:Iron-Binding Proteins; D000520:alpha-Glucosidases; D000096923:Frataxin; C509951:GAA protein, human
keywords: CEREBELLAR ATAXIA