MRI-derived glymphatic-related composite captures brain and cognitive vulnerability associated with cardiovascular risk in older adults

We evaluated a multimodal magnetic resonance imaging (MRI)-derived glymphatic-related composite and examined its associations with cardiovascular risk, brain structural integrity, and cognition in older adults.

Ninety-two participants were included in the baseline analyses and 68 in the 6-month reassessment analyses. Cardiovascular risk was estimated using the Prediction for ASCVD Risk in China 10-year atherosclerotic cardiovascular disease score. The glymphatic-related composite integrated six MRI-derived measures: choroid plexus volume, choroid plexus free-water fraction, diffusion tensor image analysis along the perivascular space index, blood oxygen level-dependent signal-cerebrospinal fluid coupling, basal ganglia perivascular spaces, and deep white matter perivascular spaces. Outcomes included cortical thickness in Alzheimer's disease (AD)-vulnerable regions, peak width of skeletonized mean diffusivity, and cognitive performance.

Higher cardiovascular risk was associated with lower glymphatic-related composite scores and lower cortical thickness in AD-vulnerable regions at baseline and the 6-month reassessment. Higher cardiovascular risk was also indirectly associated with poorer flanker task performance through the glymphatic-related composite at both assessments.

The MRI-derived glymphatic-related composite showed consistent associations with cardiovascular risk and cognitive vulnerability across repeated assessments and may serve as a summary measure of glymphatic-related MRI features in older adults.