The UHDRS and UHDRS-FAP assessments in Huntington's disease

Abstract

Huntington’s disease (HD)

is a progressive neurodegenerative disorder, which is clinically characterized

by motor impairment, cognitive decline, and behavioral symptoms. In this thesis

we have investigated measurement properties of the Unified Huntington’s Disease Rating Scale (UHDRS) and the Unified Huntington’s Disease Rating Scale-For Advanced Patients (UHDRS-FAP). These assessment scales have been developed to monitor the presence, severity, and progression of symptoms systematically over time. To measure change of symptoms accurately, reliable and valid scales are essential. Poor interrater reliability was found for all dystonia items of the UHDRS. We concluded that the rating of these items is difficult to interpret, probably as a consequence of the subjective nature of the response options. Future studies are required to explore how the dystonia items can be improved. We have also demonstrated that the motor and cognitive scores of the UHDRS-FAP deteriorated in patients with advanced HD during six months follow-up, while the motor and cognitive scores of the UHDRS did not show any change. This finding suggests that the UHDRS-FAP can detect disease progression in late stage HD, contrary to the UHDRS. Therefore, we recommended the use of the UHDRS-FAP motor and cognitive scores in long-term care facilities to optimize HD care.