Eighty non-demented PD patients in early and middle stages and 86 healthy controls were invited to participate in this study. Neuropsychological batteries testing executive function, visuospatial function, memory and attention were evaluated. Cognitive impairments were defined as impaired performance in at least one cognitive domain.
Neuropsychological batteries detected 30 cases with executive dysfunction, 27 cases with memory impairment, eight cases with visuospatial dysfunction and seven cases with attention impairment. As many as 48 cases (60 % ) of PD patients presented cognitive impairment. Logistic regression analysis indicated that education level and Hoehn & Yahr stage were associated with cognitive impairment in PD.
Cognitive impairment is common in the early and middle stages of PD without dementia; executive function is the most common domain impaired in a Chinese PD population. Cognitive impairment might be predicted by lower education level and higher Hoehn and Yahr stage.