Quantitative assessment of the evolution of cerebellar signs in spinocerebellar ataxias

• Published in: Movement disorders Vol. 26; no. 3; pp. 534 - 538
• Main Authors: Chan, Ellis, Charles, Perrine, Ribai, Pascale, Goizet, Cyril, Marelli, Cecilia, Vincitorio, Carlo-Maria, Bayon, Alice Le, Guyant-Maréchal, Lucie, Vandenberghe, Nadia, Anheim, Mathieu, Devos, David, Freeman, Leorah, Ber, Isabelle Le, N'Guyen, Karine, Tchikviladzé, Maya, Labauge, Pierre, Hannequin, Didier, Brice, Alexis, Durr, Alexandra, du Montcel, Sophie Tezenas
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.02.2011; Wiley; Wiley Subscription Services, Inc
• Subjects: Adult; Analysis of Variance; Biological and medical sciences; Cerebellum - pathology; Cerebellum - physiopathology; clinical neurology examination; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Disability Evaluation; Disease Progression; Female; Follow-Up Studies; gait disorder/ataxia; Humans; Male; Medical sciences; Middle Aged; Movement disorders; Neurology; outcome research; responsiveness; Sample Size; Severity of Illness Index; spinocerebellar ataxia; Spinocerebellar Ataxias - diagnosis; Spinocerebellar Ataxias - physiopathology; Statistics as Topic; Young Adult; Gait disorder; Nervous system diseases; Prognosis; Cerebellar ataxia; clinical neurology examination; Genetic disease; responsiveness; Neurology; Spinocerebellar ataxia; Central nervous system disease; Evolution; gait disorder/ataxia; Degenerative disease; Sign; outcome research
• ISSN: 0885-3185; 1531-8257
• DOI: 10.1002/mds.23531

Background: Responsive ataxia rating scales are essential for determining outcome measures in clinical trials. Methods: We evaluated the responsiveness over time of the composite cerebellar functional severity score, a quantitative score measuring cerebellar ataxia in 133 patients with autosomal dominant cerebellar ataxias (ADCA), which were prospectively evaluated at inclusion and after one‐year of follow‐up. A more responsive tool was developed, the Cerebellar Functional Severity score writing, incorporating the writing test at dominant hand to the Cerebellar Functional Severity score. Results: Within the one‐year follow‐up period, the Cerebellar Functional Severity score and its writing version increased significantly and the Scale for the Assessment and Rating of Ataxia decreased significantly reflecting increased severity of the cerebellar symptoms. The Cerebellar Functional Severity score writing responsiveness was best in genotypes SCA1, 2, and 3 compared with the other genotypes (effect size = 0.196, standardized response mean (SRM) = 0.624 versus effect size = −0.051, SRM = −0.150). The Cerebellar Functional Severity score writing used as an outcome measure would require only 163 SCA1, 2, or 3 patients per group in a two‐arm interventional trial for a 50% reduction in progression and 80% of power. Discussion: Our study demonstrates that the Cerebellar Functional Severity score and Cerebellar Functional Severity score writing are responsive quantitative scores for evaluating sensitivity to change in ADCA patients and can be used as outcome measures in clinical trials, especially when targeting genotypes SCA1, 2 and 3. © 2011 Movement Disorder Society