Differentiation of Alzheimer's disease and Huntington's disease with the Dementia Rating Scale

Patients with dementia of the Alzheimer type (DAT) and Huntington's disease (HD) were assessed with the Dementia Rating Scale, a brief mental status examination that provides a global dementia score and subtest scores for attention, initiation, construction, conceptualization, and memory capacities. Although the patients with DAT and the patients with HD were precisely matched in terms of total Dementia Rating Scale score, different subtest score profiles emerged. Patients with DAT were more impaired than patients with HD on the Memory subtest, whereas patients with HD were more impaired than patients with DAT on the initiation subtest. These results are indicative of qualitative differences in the cognitive impairment of the two disorders and demonstrate that such differences can be elucidated with brief mental status examinations.