The neuropsychiatric profile of Parkinson's disease subjects with and without mild cognitive impairment

Neuropsychiatric symptoms (NPS) are common clinical features of Parkinson's disease (PD). However, NPS profiles in PD subjects with mild cognitive impairment (MCI) have scarcely been investigated. We aimed to describe the NPS profiles of non-demented PD subjects with and without MCI. A total of 410 non-demented PD subjects were included. Of these, 164 were cognitively normal PD subjects (PD-cn), 142 PD had amnestic MCI (PD-aMCI), and 104 had PD with non-amnestic MCI (PD-naMCI). NPS were evaluated in accordance with the Neuropsychiatric Inventory (NPI). PD-aMCI subjects revealed the highest NPS burden, followed by PD-naMCI and then PD-cn. Overall, the most common NPS in PD-MCI were in order: depression, sleep disturbance, anxiety and apathy. Irritability was significantly associated with PD-aMCI and PD-naMCI. Prospective studies are required to evaluate the significance, clinical correlates and prognostic role of NPS in subject with PD-MCI.