Objective: To compare the characteristics of naming impairment in Parkinson's disease (PD) without dementia, Parkinson's disease dementia (PDD) and Alzheimer's disease (AD).
Methods: All participants came from outpatient clinic or inpatients of our hospital during 2011-2013. Object and action naming tests were evaluated among patients with PD without dementia (n=60), PDD (n=60), AD (n=60) and healthy control group (n=60).
Results: The object naming score of PD without dementia group was 40.2±2.8, PDD group was 36.0±3.1, AD group was 31.6±4.0 and healthy control group was 44.1±2.2, while the action naming score of PD without dementia group was 27.3±2.6, PDD group was 20.5±4.0, AD group was 22.5±2.7 and healthy control group was 31.6±1.4. The object and action naming were both impaired in PD without dementia, PDD and AD patients compared with healthy control group (P<0.01).
Conclusions: PD patients without dementia have slight object and action naming impairments with more impairments in action naming. Action naming is more impaired in PDD patients, while object naming is more impaired in AD patients.