Memory and Cognitive Impairment in Parkinson's Disease

Parkinson’s disease (PD) is a neurodegenerative condition which is characterized by asymmetrical, slowly progressive akinetic rigid syndrome with tremors. Strictly speaking, cognitive impairment or memory problems is not a feature of Idiopathic Parkinson’s disease (IPD). In fact, dementia within the first few years of onset of PD is one of the exclusion criteria in diagnosis. 1 Over the last few decades, there have been several studies where patients with IPD have been demonstrated to have significant cognitive deficits. To further complicate the issue, it has been reported that dopaminergic drugs are associated with either induction or worsening of cognition in PD patients. The instruments used for the evaluation of cognitive functions in PD are not standardized, lack homogeneity or reproducibility for evaluating patients in different stages of PD and different studies have used different criteria for their evaluation of cognition in PD. This leads to a wide variation in the test results. The present communication attempts to evaluate the magnitude and the spectrum of memory and cognitive impairment in patients of PD in a manner that is evidence based.