Cognitive changes in Parkinson's disease patients with visual hallucinations.

OBJECTIVE

To evaluate the decline in specific neuropsychological functions in nondemented Parkinson's disease (PD) patients with a history of visual hallucinations (VH).

METHODS

Twenty PD patients with VH, 20 PD patients without VH and 18 normal controls were followed up over a 1-year period and assessed for cognitive decline.

RESULTS

Forty-five percent of nondemented hallucinating PD patients developed dementia during the 1-year period between baseline and follow-up evaluations. Of the nondemented hallucinating PD patients nearly 70% showed impairment in multiple cognitive domains. The progressive decline in hallucinating PD patients affected mainly visual memory for faces and visuoperceptive-visuospatial functions.

CONCLUSION

Our results support a fast impairment of complex visual functions in hallucinating PD patients, but also a progressive decline in multiple cognitive domains, which have been identified as a risk of developing dementia in PD.