Cube drawing performances in normal ageing and Alzheimer's disease: data from the PAQUID elderly population-based...

To assess the influence of age and other sociodemographical variables, depressive symptomatology and the occurrence of Alzheimer's disease (AD) on cube drawing, we examined the performance of 858 normal subjects and 17 incident AD patients in the PAQUID population-based study. Cube drawing was first performed on verbal command and, in case of failure, a model of a cube was given to the subjects to copy. Normal subjects had some difficulties in drawing a cube on verbal command, evidenced by 40% failure in the drawing-to-command condition, while only 17% still failed in the drawing-to-copy condition. Multivariate logistic regressions showed that age, gender, and educational level were associated with cube drawing failure in both conditions, but depressive symptomatology was only associated with persistent failure in the drawing-to-copy condition. Seventy-six point five percent of incident AD subjects failed in the drawing-to-command condition and 64.7% did not benefit from the presentation of the model. Analysis showed that persistent failure in the copy condition was the best level of differentiation between normal and AD subjects.