Mild cognitive impairment in Parkinson's disease: the Parkinson's disease cognitive study (PACOS).

Approximately 30% of Parkinson's disease (PD) patients show impaired cognitive performance, which is suggestive of Mild Cognitive Impairment (MCI), representing a predictor of dementia, especially when present at diagnosis. The objective of the study was to evaluate the frequency and clinical predictors of MCI in a large hospital-based cohort of PD patients. We collected cross-sectional data from the Parkinson's disease cognitive impairment study (PACOS), a multicenter study involving two Movement Disorder centers, which are located in south Italy.