[Comparison of cognitive functions and neuropsychiatric symptoms between patients with Parkinson's disease dementia and Alzheimer's disease].

Objective To compare the cognitive functions and neuropsychiatric symptoms of Parkinson′s disease dementia (PDD) versus Alzheimer′s disease (AD). Methods Patients fulfilling the diagnostic and statisticalmanual ofmental disorders, 4thedition (DSM-Ⅳ) dementia diagnosis criteria were recruited into this case-control study.AD patients were diagnosed with the criteria of National Institute of Neurologic and Communicative Disorders and Stroke and Alzheimer′s Disease and Related Disorders Association (NINCDS-ADRDA) while PDD was based upon the standards of Movement Disorder Society (MDS) Task Force.According to clinical dementia rating (CDR) score, they were divided into mild dementia (CDR score=0.5/1) and moderate-to-severe dementia groups (CDR score=2/3).World Health Organization-University of California, Los Angeles, auditory verbal learning test (WHO-UCLA AVLT), clock drawing test (CDT) and neuropsychiatric inventory (NPI) were performed. Results No significant difference in immediate memory, delayed memory or long-delayed recognition score was observed between PDD and AD patients (P>0.05).CDT score was significantly lower in PDD patients (mild dementia group: 0.9±0.9; moderate-to-severe dementia group: 0.6±0.9) than that of AD patients (mild dementia group: 1.5±0.7, P<0.001; moderate-to-severe dementia group: 1.1±0.6, P=0.027) and this difference wasmore significant inmild dementia group.More than 70% of PDD patients reported at least one neuropsychiatric symptom.And also, in mild dementia group, compared with AD patients (frequency: 43.2% (16/37), NPI score=5.7±11.9), a higher frequency of neuropsychiatric symptoms and higher NPIscores were observed in PDD patients (frequency: 71.40% (25/35), NPI score=8.4±9.8). Conclusion More severe impairment in visuospatial ability and executive function was present in PDD patients compared with AD patients.And neuropsychiatric symptoms weremore common and severe in PDD patients. Key words: Alzheimer′s disease;  Parkinson′s disease dementia; Cognitive function;  Behavioral symptoms; Case-control study