Objective: To compare cognitive impairments in dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), to discriminate between the two entities.
Methods: 10 DLB and 12 PDD consecutive patients performed a neuropsychological battery designed to assess several cognitive domains: verbal and visual memory (Delayed Matching to Sample (DMS)-48), language, gnosia, praxia and executive functions.
Results: DLB patients had poorer performances in orientation (p<0.05), Trail Making Test A (p<0.05) and reading of names of colours in the Stroop Test (p<0.05). Their scores were also lower in the visual object recognition memory test (DMS-48), in both immediate (p<0.05) and delayed recognition (p<0.05). No differences were observed in the other tests.
Conclusion: Despite global similarities in cognitive performances between DLB and PDD patients, we observed important differences: in particular, DMS-48, a test of visual object recognition memory and visual storage capacity, was poorer in DLB patients.