Annual Change in Friedreich's Ataxia Evaluated by the Scale for the Assessment and Rating of Ataxia (SARA) is Independent of Disease Severity

Background: The objective of the study was to evalu- ate the sensitivity to change of the Scale for the Assessment and Rating of Ataxia (score, 0-40) in Frie- dreich's ataxia. Methods: This was a follow-up study in adult patients with genetically confirmed Friedreich's ataxia evaluated at least twice (minimum interval, 6 months). Participants were outpatients at the Center for Neurogenetics of the Pitie-Salpetriere Hospital in Paris. Results: We included 84 patients; 60% had 3 or more evaluations. The mean score on first assessment was 22.7 6 9, and the mean follow-up was 1.84 6 1.10 years. The mean increase was 1.36 6 2.3 points/ year; this variation was not significantly linked to fac- tors known to influence disease severity such as age at onset, disease duration, GAA expansion length, and wheelchair use. Conclusions: In adult Friedreich's ataxia patients the Scale for the Assessment and Rat- ing of Ataxia can detect annual changes independently of disease severity. In future therapeutic trials no patient stratification is globally required. V C 2011 Move- ment Disorder Society