Cognitive profiles in Mild Cognitive Impairment (MCI) patients associated with Parkinson's disease and cognitive disorders

Background: Mild cognitive impairment (MCI) is rapidly becoming one of the most common clinical manifestations affecting the elderly and represents an heterogeneous clinical syndrome that can be ascribed to different etiologies; the construct of MCI in Parkinson's disease (PD) (MCI-PD) is more recent but the range of deficits is still variable. Early recognition and accurate classification of MCI-PD could offer opportunities for novel therapeutic interventions to improve the natural pathologic course. Objective: To investigate the clinical phenotype of amnestic mild cognitive impairment (aMCI) and in patients with PD and MCI (MCI-PD). Materials and Methods: Seventy-three patients with aMCI and in 38 patients with MCI-PD were enrolled. They all underwent Mini-mental State Examination (MMSE), the Rey auditory-verbal learning test and the immediate visual memory (IVM) item of the Mental Deterioration Battery, the Rey auditory-verbal learning test included the Rey-immediate (Rey-I), and the delayed recall of the word list (Rey test deferred, Rey-D). The Geriatric Depression Scale (GDS) was used for mood assessment. Results: The results of the Rey-I and Rey-D and of the IVM item showed statistically significant differences between the aMCI and the MCI-PD group. The mean Rey-I and Rey-D score was significantly lower as well as the IVM score was higher in patients with aMCI than in those with MCI-PD, aMCI patients showed greater impairment in long-term memory, whereas more aMCI than MCI-PD patients had preserved attention, computation, praxis, and conceptualization. Conclusions: Our findings demonstrate that the cognitive deficit profile is specific for each of the two disorders: Memory impairment was a typical feature in aMCI patients while MCI-PD patients suffered from executive functions and visuospatial attention deficits.