The Dementia Rating Scale (DRS) in the diagnosis of vascular dementia

Abstract – The Dementia Rating Scale (DRS) is considered a very useful instrument to assess patients with dementia. The tasks are grouped into fi ve subscales, each one evaluating different cognitive areas, namely: Atten-tion, Initiation/Perseveration (I/P), Construction, Conceptualization and Memory. Objective: To verify the ability of the DRS in discriminating vascular dementia (VaD) patients from healthy controls and VaD from Alzheimer disease (AD) patients. Methods: The DRS was applied to 68 patients with mild dementia (12 with VaD and 56 with AD) and 60 healthy controls. The clinical diagnosis was made by two neurologists based on the patients´ history, laboratory and neuroimaging results and neuropsychological tests. Results: In the comparison between VaD patients and controls, the subscales I/P, Memory, Conceptualization and Attention were those displaying best discrimination between the two groups. The cutoff <124 yielded 93.3 % of sensitivity and 91.7 % of specifi c-ity for the diagnosis of VaD. Only the I/P subscale differentiated VaD from AD patients. Conclusions: The DRS was found to be a useful instrument to discriminate VaD patients from controls. VaD patients showed worse performance in tasks of executive functions than AD patients. Executive dysfunction, evaluated through the I/P subscale of the DRS, might be useful in differentiating between VaD and AD patients. Key words: dementia, neuropsychological tests, cognitive disorders, Alzheimer disease, vascular dementia. A Escala de Avaliação de Demência (DRS) e o diagnóstico de demência vascula