Structural Volumetric Alterations in Parkinson's Disease With Mild Cognitive Impairment.

Research overview

The text below is the source article’s original abstract under a verified reuse license. cc by

BackgroundParkinson's disease with mild cognitive impairment (PD-MCI) is a critical dementia prodrome, but its structural neuropathology remains incompletely defined. While hippocampal atrophy is established, volumetric changes in other subcortical structures are poorly characterized.ObjectiveTo perform the first comprehensive meta-analysis quantifying gray matter volume alterations across six subcortical regions in PD-MCI.MethodsA systematic search of PubMed, Web of Science, Embase, and Cochrane (inception-June 2025) for studies reporting MRI volumetric data comparing PD-MCI and cognitively normal PD (PD-NC) was done. Random-effects models calculated pooled weighted mean differences (WMDs) with 95% confidence intervals (CIs). Heterogeneity (I2), publication bias, sensitivity analyses, and meta-regression were assessed.ResultsPD-MCI showed significant bilateral atrophy versus PD-NC in the hippocampus (total WMD = -0.65 cm3), thalamus, putamen, and amygdala, alongside right-lateralized globus pallidus atrophy (WMD = -0.08 cm3). Bilateral caudate nuclei volumes were preserved. Sensitivity analyses confirmed robustness. Meta-regression identified segmentation tools and country as sources of left hippocampal heterogeneity (p ConclusionPD-MCI exhibits a distinct subcortical atrophy signature involving limbic-striato-thalamic networks, with right globus pallidus atrophy as a novel lateralized biomarker. Network-based imaging paradigms are advocated, requiring standardized protocols and longitudinal validation.Systematic review registrationIdentifier PROSPERO (CRD420251051275).

Related topics