Greater White Matter Hyperintensities and More Severe Cognitive Dysfunction in Mild Cognitive Impairment With Motoric Cognitive Risk Syndrome.

Background: The motoric cognitive risk syndrome (MCRS) is characterized by slow gait and cognitive complaints. A motor-based approach to MCRS provides a clinical strategy for identifying individuals at high risk for dementia.

Methods: This study included 81 outpatients with mild cognitive impairment (MCI). All participants underwent clinical evaluations, including volumetric brain magnetic resonance imaging (MRI) and neuropsychological testing with the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet. White matter hyperintensities (WMH) volume was calculated using automated segmentation analysis from three-dimensional MRI images. MCRS was defined by the presence of cognitive complaints and slow gait defined as gait speed at least one standard deviation below age- and sex-specific means.

Results: A total of 31 subjects with MCRS and 50 subjects without slow gait participated in this study. The linear regression analysis revealed a significant negative relationship between WMH volume and gait speed in both the MCI group with MCRS (β = -1.010, P < 0.001) and the MCI group without slow gait (β = -0.427, P = 0.016). Both age (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.02-1.34) and WMH volume (OR, 1.11; 95% CI, 1.01-1.22) were significantly associated with MCRS, even after adjusting for confounding factors. After applying Bonferroni correction (P < 0.0036), the MCRS group exhibited significantly worse performance on word list memory, word list recall, and MMSE-KC compared to the MCI group without slow gait.

Conclusion: MCRS represents a distinct and more severe clinical entity within the MCI population, characterized by greater cognitive impairment and increased WMH burden.