EARLY COGNITIVE AND MOTOR SYMPTOMS IN IDENTIFIED CARRIERS OF THE GENEFOR HUNTINGTON-DISEASE

Objective: To study early motor and cognitive symptoms in Huntington d isease. Design: A follow-up cohort study after a DNA test pro cedure i n which gene carriers and noncarriers were identified among people gen etically at risk for Huntington disease. Setting: Leiden University Me dical Center, Department of Neurology, Leiden, the Netherlands, in coo peration with the Clinical Genetics Center Leiden and the Department o f Medical Psychology and Psychotherapy, Erasmus University Rotterdam, Rotterdam, the Netherlands. Participants: Thirty-three individuals: 9 unaffected gene carriers, 6 gene carriers with motor symptoms, and 18 noncarriers of the gene for Huntington disease. Main Outcome Measures: A neuropsychologic examination covering a broad area of cognitive fun ctioning, reaction time procedures, and motor tasks. Results: The neur opsychologic assessment showed no significant differences between pres ymptomatic gene carriers and noncarriers. Three motor tasks differenti ated between these 2 groups on a liberal .05 P level (analysis of vari ance followed by the Student t test). The affected gene carriers perfo rmed less well than the presymptomatic gene carriers acid the noncarri ers in 10 motor tasks and 7 cognitive tasks. These differences were si gnificant at P<.05. Conclusion: Motor symptoms play a more prominent a nd unequivocal role than cognitive symptoms in early stages of Hunting ton disease.