Predictors of cognitive impairment in multiple system atrophy.

OBJECTIVE: To determine predictors of cognitive impairment and frontal dysfunction in patients with multiple system atrophy (MSA).

METHODS: We recruited 59 patients with MSA and determined the predictors of a decline in the Mini-Mental State Examination (MMSE) and Frontal Assessment Battery (FAB) scores.

RESULTS: The MMSE scores negatively correlated with disease duration, Unified MSA Rating Scale (UMSARS) part 1 and 4 scores, and residual urine volume, and positively correlated with the coefficient of variation of electrocardiographic RR intervals. The FAB scores negatively correlated with the UMSARS part 2 score, periventricular hyperintensity grade, and deep white matter hyperintense signal grade. A significant predictor of rapidly progressive cognitive impairment was a high residual urine volume.

CONCLUSIONS: Impairment of global cognitive function correlates with the long-term disease duration, global disability due to the disease, and autonomic dysfunction, whereas frontal dysfunction correlates with motor function and degeneration of cerebral white matter.