Mild cognitive impairment in Parkinson's disease: current view

Area of Science:

• Neuroscience
• Neurology
• Cognitive Science

Background:

• Parkinson's disease (PD) is a common neurodegenerative disorder often preceded by mild cognitive impairment (MCI).
• MCI affects executive function, attention, memory, and visuospatial abilities, increasing dementia risk in PD patients.
• Prevalence of MCI in de novo PD patients is ~30%, rising to 75% after 10 years, with up to 60% progressing to dementia.

Purpose of the Study:

• To review the epidemiology, clinical features, neuroimaging, and morphological changes in PD with MCI (PD-MCI).
• To discuss available biomarkers and the heterogeneous pathobiological mechanisms underlying PD-MCI.
• To emphasize the need for longitudinal studies to clarify PD-MCI pathogenesis for improved diagnosis and treatment.

Main Methods:

• Review of epidemiological, clinical, and neuroimaging data related to PD-MCI.
• Analysis of neuropathological findings and biomarker studies in PD-MCI.
• Discussion of pathobiological mechanisms and heterogeneity in PD-MCI.

Main Results:

• PD-MCI exhibits characteristic EEG slowing, frontotemporal hypoperfusion, and decreased functional connectivity.
• Cognitive phenotypes in PD-MCI are heterogeneous, suggesting multifactorial neurodegenerative processes.
• Neuropathological data for PD-MCI show varied morphological changes, similar to MCI in other conditions.

Conclusions:

• PD-MCI is a complex condition with diverse underlying pathobiological mechanisms.
• Further longitudinal clinico-pathological studies are essential to understand PD-MCI.
• Identifying reliable fluid and neuroimaging biomarkers is critical for early diagnosis and therapeutic strategies.