Accuracy of the semantic fluency test to separate healthy old people from patients with Alzheimer’s disease in a low education population

Acurácia do teste de fluência semântica para separar pessoas saudáveis de pacientes com doença de Alzheimer em uma população de baixa escolaridade

Objective  Evaluate the accuracy of two semantic categories of the verbal fluency test (supermarket and animal categories) to separate healthy elderly individuals and lower educated Alzheimer’s disease patients.

Methods  We evaluated 69 older adults with less than 5 years of schooling, consisting of 31 healthy elderly, and 38 patients diagnosed with Alzheimer’s disease. Semantic verbal fluency was evaluated using the animal and supermarket categories. Mann-Whitney U and Independent t Tests were used to compare the two groups, and the diagnostic accuracy of the tests was analyzed by sensitivity, specificity, likelihood ratio’s, and the Area Under the Curve (AUC).

Results  We found a significant difference between the healthy older and Alzheimer’s disease groups, in both, animal (p = 0.014) and supermarket verbal fluency (p < 0.001). The supermarket category showed better overall diagnostic accuracy (AUC = 0.840, 95% CI = 0.746-0.933; p < 0.001) compared to the animal category (AUC = 0.671, 95% CI = 0.543-0.800; p = 0.014).

Conclusion  The supermarket category of semantic verbal fluency provides better accuracy than the animal category for the identification of dementia in a Brazilian elderly population with low educational level.

Semantic verbal fluency; low education; elderly; Alzheimer’s disease