Jiˇ rí Klempíˇ r a Olga Klempíˇ rová a Nataˇ sa ˇ Spaˇ cková a Jana ˇ Zidovská b Jan Roth a a Department of Neurology, Charles University, 1 st Medical Faculty, Prague, Czech Republic b Institute of Biology and Medical Genetics, Charles Uni- versity, 1 st Medical Faculty, Prague, Czech Republic Reprint requests to: Dr Jiˇ rí Klempíˇ r, Dept of Neurology, 1 st Medical Faculty, Charles Univer- sity, Kateˇ rinská 30, Prague 2, Czech Republic E-mail: jiri.klempir@seznam.cz Accepted for publication: December 28, 2006 Summary The purpose of this study was to test the usefulness of the Unified Huntington’s Disease Rating Scale (UHDRS) in clinical practice. The UHDRS was used to examine 45 persons with ge- netically diagnosed Huntington’s disease (HD) in vari- ous stages. The rate of motor involvement, cognitive deficit and re- liance on nursing care rose in linear proportion to HD duration. The severity of motor involvement correlated significantly with all UHDRS subscales except for that of behavioral disorders, the rate of these disorders be- ing unrelated to any of the parameters under study. The number of CAG triplets was inversely correlated with the age at onset of HD. Being considerably time consuming, administration of the whole UHDRS calls for interdisciplinary co-opera- tion. For valid data acquisition, the participation of caregivers is also essential. In clinical practice it is ad- visable regularly to monitor the patient’s conditions and the efficacy of treatment using the UHDRS motor, functional and behavioral subscales. Cognitive tests present difficulties but, in view of the progressive cog- nitive deterioration in HD, they are very useful in the early stage of the disease. The UHDRS does not assess impaired voluntary motor activity, or furnish informa- tion relating to therapy, dysphagia, weight loss, sexual problems or drug abuse. KEY WORDS: behavioral disorders, CAG triplets, cognitive deficit, executive dysfunction, Huntington’s disease, Unified Hungington’s disease rating scale. Introduction Huntington’s disease (HD) is an autosomal dominant in- herited neurodegenerative disease. The main symp- toms of HD are choreatic movements with impaired vol- untary motor activity, behavioral disorders, and progres- sive cognitive deterioration leading to dementia. A number of scales and batteries of tests designed to evaluate the HD patient’s motor and cognitive deficits, behavioral disturbances, and daily activities are in use worldwide (1-4). In 1996, an international Huntington’s Disease Study Group (5) came forward with their Unified Huntington’s Disease Rating Scale (UHDRS). This is a collection of scales, tests and questionnaires allowing comprehen- sive clinical rating of HD severity. The UHDRS assess- es the severity of motor impairment (UHDRS-motor as- sessment, UHDRS-M), as well as the degree of cogni- tive deterioration (cognitive assessement, UHDRS-psy- chology UHDRS-P). Disorders of behavior and of men- tation are investigated by means of the UHDRS-behav- ioral assessment (UHDRS-B). Questionnaires such as UHDRS-functional assessment (UHDRS-F), UHDRS-in- dependence (UHDRS-I) and UHDRS-functional capaci- ty (UHDRS-C) are designed to evaluate HD patients’ self-care, and social and financial needs. The purpose of the present study was to evaluate the usefulness of the UHDRS in clinical practice and to clar- ify the relationship between motor, cognitive and behav- ioral findings and CAG triplet repeats. Materials and methods We studied 45 patients (17 men, 28 women) with genet- ically confirmed HD in various stages. The following parameters were assessed: actual age, age at clinical onset and duration of HD (retrospectively established), and pathological number of CAG triplet re- peats (Table I, over). The patients were tested in accordance with the UHDRS protocol (5). A neurologist assessed the severity of the motor symptomatology, as well as the patients’ behavior, independence and functional capacity. The neuropsychological examination, on the other hand, was performed by a clinical psychologist using the Czech version of cognitive tests, in particular: the Digit Symbol Modalities Test (DSMT) (6), the Verbal Fluency Test (VF) (7), and the Stroop Test. In particular, the shortened (45-second) Stroop Test used in the UHDRS was replaced by a Czech version of a previous, unpub- lished adaptation of the Stroop Test (Regard M. Cogni- tive rigidity and flexibility: a neuropsychological study. Ph.D. dissertation, University of Victoria, British Colum- bia, 1981). Functional Neurology 2006; 21(4): 217-221 217 Unified Huntington’s Disease Rating Scale: clinical practice and a critical approach