Subclinical Atherosclerosis Markers in Alzheimer's and Vascular Dementia: A Cross-Sectional Comparison with Healthy Controls.

Abstract

Introduction: Vascular mechanisms are increasingly implicated in the pathophysiology of Alzheimer's disease and vascular dementia. This study aimed to evaluate the association between subclinical atherosclerosis markers and cognitive performance in patients with Alzheimer's disease and vascular dementia compared with healthy controls.

Methods: This cross-sectional study included 79 patients with Alzheimer's disease, 69 patients with vascular dementia, and 69 age- and sex-matched controls. Vascular markers were measured, and cognitive function was assessed using the Mini-Mental State Examination. Correlation, multivariable regression, and receiver operating characteristic analyses were performed.

Results: The dementia groups had greater epicardial fat thickness (Alzheimer's disease: 6.49 ± 0.93 mm; vascular dementia: 6.36 ± 1.04 mm) than controls (5.77 ± 0.87 mm, p < 0.001). Carotid intima- media thickness was higher (0.53 ± 0.08 mm and 0.55 ± 0.10 mm versus 0.48 ± 0.08 mm, p < 0.001). Carotid distensibility and strain were lower in dementia (0.21 ± 0.03 and 10.26 ± 1.58; 0.21 ± 0.03 and 9.93±1.77) than in controls (0.25 ± 0.05 and 11.3 ± 1.75, p < 0.05). Mini-Mental State Examination scores correlated negatively with epicardial fat thickness (r = -0.30) and carotid intima- media thickness (r = -0.27), and positively with distensibility (r = 0.40) and strain (r = 0.31). Epicardial fat thickness (area under the curve 0.716) and carotid intima-media thickness (0.678) showed moderate ability to distinguish dementia from controls.

Discussion: These findings support a significant association between vascular structural and functional alterations and cognitive impairment.

Conclusion: Subclinical atherosclerosis markers were significantly associated with cognitive impairment; however, causal relationships cannot be inferred due to the cross-sectional design. These markers may support early identification and risk stratification of dementia.