Featured ArticleCarotid plaque as a predictor of dementia in older adults: The Three-City Study

BackgroundThe contribution of carotid atherosclerosis to incident dementia remains unclear. We examined the association between carotid plaques (CP) and common carotid intima media thickness (CCA-IMT) with incident dementia and its subtypes, and their added value for dementia risk prediction.MethodsAt baseline, 6025 dementia-free subjects aged 65-86 years underwent bilateral carotid ultrasonography measures of CP and plaque-free CCA-IMT. Subjects were followed-up over 7 years for the detection of dementia.ResultsAfter a mean 5.4 years of follow-up, 421 subjects developed dementia including 272 Alzheimer's disease and 83 vascular/mixed dementia (VaD). Only CP were independently related to VaD (HR≥2 sites with plaques = 1.92; 95% confidence interval or CI = 1.13-3.22) and improved VaD risk prediction (continuous Net Reclassification Index = 30.1%; 95%CI = 8.4-51.7) beyond known dementia risk factors. Accounting for stroke or competing risk by death marginally modified the results.ConclusionIn older adults, CP are independent predictors of incident VaD and may improve VaD risk prediction.