Mini-Mental State Examination subscores indicate visuomotor deficits in Alzheimer's disease patients: A cross-sectional study in a Dutch population.

AIM: In diagnostics of Alzheimer's disease (AD), the Mini-Mental State Examination (MMSE) questionnaire is frequently used to test cognitive decline. The final subtest of the MMSE, in which patients have to copy two interlocking pentagons, tests a variety of visuomotor functions. Recent imaging studies suggest that visuomotor function could decline in early stage AD, as a result of degeneration of the brain networks involved. The goal of the present study was to compare memory and visuomotor function in AD patients, reflected by the MMSE subscores for orientation, recall and interlocking pentagons.
METHODS: The MMSE subscores for orientation, recall and interlocking pentagons of 125 AD patients was extracted from their medical history. Patients were divided into three groups based on disease duration. Using related-samples Wilcoxon signed-rank tests, the performance between subtests using normalized subscores was compared within each group.
RESULTS: In all three groups, the subscores of recall and interlocking pentagons were significantly lower than orientation. No differences were found between the subscores of recall and interlocking pentagons.
CONCLUSIONS: The presented data suggest that memory function and visuomotor function are equally impaired in the present study population. This could indicate that visuomotor dysfunction might be a more important clinical feature of AD than is currently assumed. This knowledge can be used to develop new tests and markers for AD reflecting deficits in visuomotor functions, such as quantification of eye and hand movements.