Associations of Brain Morphology and Cognitive Function With Ambulatory Estimated Pulse Wave Velocity.

BACKGROUND

Inconsistent links between arterial stiffness and cognition may reflect limited cognitive tests and unaccounted diurnal pulse wave velocity variation. To bridge this knowledge gap, we investigated 24-hour ambulatory estimated pulse wave velocity (ePWV) and its association with dementia-related neuroimaging and cognitive function in hypertension.

METHODS

We assessed 893 patients with hypertension aged ≥50 years (mean age, 67.2 years; 52.3% women), including brain magnetic resonance imaging (n=545), global cognitive testing (n=623), and ambulatory ePWV measurements. White matter hyperintensity and hippocampus were quantified via Computational Anatomy Toolbox 12 and Statistical Parametric Maps 12. Cognition was assessed via the Mini-Mental State Examination and Montreal Cognitive Assessment.

RESULTS

Among 623 tested participants, the prevalence of mild cognitive impairment was 10% (Mini-Mental State Examination, n=62) and 18.5% (Montreal Cognitive Assessment, n=115). Cognitive scores decline with higher white matter hyperintensity burden and lower hippocampal volume (P≤0.024). Higher 24-hour ePWV quartiles showed graded associations with higher white matter hyperintensity volume and lower hippocampal volume (both P<0.001) and lower cognitive scores (P≤0.037). Multivariable models showed each 1-SD (+1.2 m/s) increment in 24-hour ePWV were associated with 2.00±1.74 mL greater white matter hyperintensity volume (P=0.004), and 0.54±0.14 mL smaller hippocampal volume (P<0.001), independent of age, systolic blood pressure, and other confounders. These associations persisted after further adjustment for carotid-femoral PWV, which itself showed no independent association (P≥0.18). Results were consistent for daytime and nighttime ePWV and across key subgroups.

CONCLUSIONS

Ambulatory ePWV is an independent risk factor for dementia-related brain pathology. Targeting arterial stiffness represents a promising strategy for dementia prevention.