Cognition in multiple system atrophy: neuropsychological profile and interaction with mood

We evaluated cognitive functions and mood in two groups of patients with multiple system atrophy (MSA) in order to determine the influence of mood on cognitive performance. Our aim was to differentiate between parkinsonism-predominant (MSA-P) and cerebellar-predominant (MSA-C) MSA based on those parameters. Fifteen MSA-P and 10 MSA-C patients underwent neuropsychological tests that examined executive functions (working memory, response inhibition, and verbal reproduction), verbal learning and memory, verbal and visual reasoning, and processing speed. Anxiety and depression were also assessed. The findings on their cognitive performance and mood were compared to those of healthy controls and also discussed in relation to a group of Parkinson's disease (PD) patients. The results showed that cognitive and mood characteristics could distinguish MSA-P from MSA-C and that anxiety and depression are related to cognitive decline. Compared with healthy controls, MSA-P patients showed reduced verbal retrieval (immediate, P < 0.019; long-term, P < 0.018) while MSA-C patients had difficulties in learning new verbal information (P < 0.022) and in controlling attention (P < 0.023). These data indicate that MSA-P and MSA-C appear to have, at least in part, different cognitive and mood profiles. The neuropsychological assessments of MSA patients should test for and then take into account their level of anxiety and depression, insofar as it might have an adverse effect on their cognitive performance.