Subtle visuo-cognitive deficits as a potential early marker of cognitive decline

BackgroundIndividuals with subjective cognitive decline (SCD) report declining cognitive abilities but do not have an objective cognitive impairment at present. Research indicates that they are at an elevated risk of developing Alzheimer's disease (AD). Identifying or developing cognitive measures capable of detecting cognitive deficits that individuals with SCD may experience is crucial, as they may benefit from additional diagnostic procedures and interventions aimed at delaying further cognitive decline.ObjectiveTo investigate whether specific cognitive tasks selected for their relevance in detecting early changes possibly related to AD can predict group membership SCD and Non-SCD.MethodsNeuropsychological assessment data of 73 older adults (35 SCD, 38 Non-SCD) was analyzed. Logistic regression analyses, classification metrics, and receiver operating characteristic curves were used to evaluate the predictive power of a model including a verbal fluency, word list learning, and constructional praxis test.ResultsIndividuals with SCD were older and reported higher levels of depression. The logistic regression model demonstrated limited sensitivity (0.54) but high specificity (0.87). Constructional Praxis (visuo-spatial- and constructional abilities) emerged as a significant predictor (OR = 0.49, 95% CI: 0.26-0.86, p < 0.05), even in an additional model controlling for affective symptoms. Better performance in this task was associated with lower odds of belonging to the SCD group.ConclusionsExisting cognitive assessments appear to lack sensitivity in the context of SCD. Visuo-cognitive functioning may represent a promising domain for the development of more sensitive diagnostic tools to detect possible cognitive alterations that individuals with SCD may experience.