Background: The purpose of the present study was to examine the relationship between
cognitive impairment and the performance of handwritten scripts presented as “letter-writing”
to a close relative by patients with dementia Lewy bodies (DLB), as fluctuations of the symptoms
phase, and in a matched group of patients with Alzheimer’s disease (AD). The degree of
writing disability and personal, spatial, and temporal orientation was compared in these two
groups.
Design and methods: Fourteen simple questions, designed in a form that could be utilized
by any general practitioner in order to document the level of cognitive functioning of each
patient, were presented to 30 AD patients and 26 DLB patients. The initial cognition test was
designated PQ1. The patients were examined on tests of letter-writing ability. Directly after
the letter-writing, the list of 14 questions presented in PQ1 was presented again in a repeated
procedure that was designated PQ2. The difference between these two measures (PQ1 – PQ2)
was designated D∆. This test of letter-writing ability and cognitive performance was administered
over 19 days.
Results: Several markedly strong relationships between dysgraphia and several measures of
cognitive performance in AD patients and DLB patients were observed, but the deterioration
of performance from PQ1 to PQ2 over all test days were markedly significant in AD patients
and not significant in DLB patients. It is possible that in graphic expression even by patients
diagnosed with moderate to relatively severe AD and DLB there remains some residual capacity
for understanding and intention that may be expressed. Furthermore, the deterioration in performance
and the differences noted in AD and DLB patients may be due to the different speed at
which the process of the protein degradation occurs for functional modification of synapses.
Conclusion: Our method can be used as part of neuropsychological tests to differentiate the
diagnosis between AD and DL