Limitations in differentiating vascular dementia from Alzheimer's disease with brief cognitive tests

Abstract

Objective: To investigate the diagnostic value of brief cognitive tests in differentiating vascular dementia (VaD) from Alzheimer's disease (AD). Method: Fifteen patients with mild VaD, 15 patients with mild probable AD and 30 healthy controls, matched for age, education and dementia severity, were submitted to the following cognitive tests: clock drawing (free drawing and copy), category and letter fluency, delayed recall test of figures and the EXIT 25 battery. Results: VaD patients performed worse than AD patients in category fluency (p=0.014), letter fluency (p=0.043) and CLOX 2 (p=0.023), while AD cases performed worse than VaD patients in delayed recall (p=0.013). However, ROC curves for these tests displayed low sensitivity and specificity for the differential diagnosis between VaD and AD. Conclusion: Although the performance of VaD and AD patients was significantly different in some cognitive tests, the value of such instruments in differentiating VaD from AD proved to be very limited. Key words: Alzheimer's disease, vascular dementia, clock drawing test, delayed recall, diagnosis, EXIT25, neuropsychological tests, verbal fluency.Limitações em diferenciar demência vascular de doença de Alzheimer através de testes cognitivos breves RESUMO Objetivo: Investigar o valor diagnóstico de testes cognitivos breves na diferenciação de demência vascular (DV) e doença de Alzheimer (DA). Método: Quinze pacientes com DV, 15 com DA provável e 30 controles saudáveis, pareados em relação à idade, escolaridade e gravidade da demência, foram submetidos aos seguintes testes: desenho do relógio espontâneo e cópia, fluência verbal semântica e fonêmica, teste de evocação de memória de figuras e a bateria EXIT25. Resultados: Pacientes com DV apresentaram pior desempenho na fluência verbal semântica (p=0,014), fonêmica (p=0,043), e no CLOX 2 (p=0,023). O grupo com DA obteve pior desempenho no teste de evocação tardia (p=0,013). As curvas ROC aplicadas a esses testes mostraram baixa sensibilidade e especificidade para o diagnóstico diferencial entre DV e DA. Conclusão: Embora o desempenho dos pacientes tenha sido diferente em alguns testes, o valor desses instrumentos para o diagnóstico diferencial entre DV e DA parece ser muito limitado. Palavras-chave: doença de Alzheimer, demência vascular, teste do desenho do relógio, memória de evocação, diagnóstico, EXIT25, testes neuropsicológicos, fluência verbal.

White matter hyperintensities, executive function and global cognitive performance in vascular mild cognitive impairment

“…Normative data available in literature for each test for comparison to scores obtained by participants (patients and NC) in this study were used [16][17][18][19] . In order to characterize the lesion load to impair cognition at a VaMCI level, a cut-off score ≥2 on mF scale (moderate to severe degree of WMH) and HA ≤1 on de Leon score (none or questionable HA) were adopted, to ensure the inclusion of subjects with relevant white matter lesions, and with hippocampal size less compatible with neurodegenerative changes.…”

Metabolic syndrome and dementia associated with Parkinson's disease: impact of age and hypertension

“…Cognitive evaluation with brief tests has demonstrated limitations in discriminating between vascular dementia and Alzheimer-type dementia 24 . Similarly, it has not been possible to demonstrate differences in cognitive evaluations when comparing patients with Parkinson's dementia and metabolic risk factors with patients who did not present dyslipidemia, arterial hypertension or diabetes.…”

The Treatment of Vascular Dementia in Acupuncture Based on Syndromes Differentiation

“…VaD and Alzheimers disease (AD) are the most common dementia syndromes in the elderly (Matioli & Caramelli, 2010). However, only a small percentage of elderly patients have 'pure AD' or 'pure VaD' (Fotuhi et al, 2009), both of which are caused by mixed aetiology and pathophysiology.…”