Cognitive impairment patterns in Parkinson’s disease with visual hallucinations

OBJECTIVES We investigated the role of stage of disease, motor status and dopaminergic treatment in cognitive impairment of Parkinson's disease (PD) patients with visual hallucination (VH) and the presence of specific cognitive impairment patterns. METHOD We compared 33 PD patients with VH (group 1) with 30 PD patients without VH (group 2) with regard to demographic characteristics and neuropsychological test scores. RESULTS The group with VH demonstrated significantly worse Short Test of Mental Status scores; the cognitive impairment pattern presented in the form of frontal dysfunction and memory deterioration. There were significant differences in Stroop duration/error, verbal fluency, Wechsler Memory Scale and Sozel Bellek Surecleri Test (a Turkish verbal learning test) scores. CONCLUSION In PD patients with VH the main pattern of cognitive impairment is frontal dysfunction and memory deterioration. Because visual perceptive functions were not different between the two groups, such deterioration may not be a primary factor in the development of VH.