Background: Mild cognitive impairment in Parkinson’s disease (PD-MCI) is a common clinical condition. Understanding
its pathology and clinical features is important for early intervention before the onset of dementia. In the past, variable
definitions and differences in neuropsychological batteries generated divergent results of the affected cognitive patterns.
Main body: The introduction of PD-MCI criteria by the Movement Disorders Society (MDS) Task Force provides a more
uniform system for defining and measuring PD-MCI and may improve the validity of future research. PD-MCI is likely to
be heterogeneous since it can coexist with Alzheimer’s disease and/ or Lewy body pathologies in PD. Pathogeneses of
neuropsychiatric disturbances, such as depression, anxiety and apathy, are associated with PD with or without MCI. In
addition, cognitive reserve formed by patients’ unique life experiences may influence the outward cognitive performance
despite the presence of the aforementioned pathogeneses and hence alter the diagnosis of MCI.
Conclusion: The overlap of cognitive impairment across different neurodegenerative diseases suggests that PD-MCI is
likely to result from a mixture of complex pathophysiologies, rather than being a distinct pathologic entity. Differentiating
MCI from other organic symptoms in PD would facilitate novel therapeutic strategies.

EB00000002369K

Available

• Mild cognitive impairment in Parkinson’s disease: a distinct clinical entity?