The effect of cognition on the association between cerebral small vessel disease burden and motor function: a...

Cerebral small vessel disease (CSVD) is a common condition among the elderly population. In patients with CSVD, imaging markers, motor function, and cognition are closely interrelated. This study aimed to analyze the effect of cognition on the association between CSVD burden and motor function.

This cross-sectional study included 134 patients with CSVD, recruited from the China Imaging-based Biobank of Cerebral Small Vessel Diseases (CIBB-CSVD) at Beijing Tiantan Hospital between January 2020 and May 2023. We obtained demographic and medical profiles, as well as the Montreal Cognitive Assessment (MoCA) score, Short Physical Performance Battery (SPPB) score, a four-point CSVD burden score determined through magnetic resonance imaging (MRI), and gait parameters evaluated using the Codamotion analysis system from all participants.

The mean age of all CSVD patients was 60 ± 12 years. The median scores for the CSVD burden, MoCA, SPPB and modified Rankin Scale (mRS) were 3 (2, 4), 20 (16, 24), 11 (9, 12) and 0 (0, 1), respectively. Significant correlations were observed between age and the CSVD burden score, MoCA score, SPPB score, speed, and stride length (P < 0.05). Patients with higher CSVD burden scores exhibited significantly lower SPPB scores, reduced speed, shorter stride length, and decreased hip and knee range of motion (ROM), as revealed by both univariable linear regression and multivariable regression analyses adjusted for age (P < 0.05). However, after further adjustment for MoCA score, only the association between CSVD burden score and SPPB score remained statistically significant (P < 0.05). Mediation analysis indicated that the MoCA score significantly mediated the associations between CSVD burden score and both SPPB score and knee ROM. The proportion of the effect mediated by the MoCA score was 33.835% for SPPB score and 40.167% for knee ROM.

The CSVD burden influences both SPPB score and knee ROM in patients with mild to moderate cognitive and motor impairments, either directly or indirectly through cognitive decline. Cognitive function, as measured by the MoCA score, plays a significant mediating role in the association between CSVD burden and both SPPB score and knee ROM.