Relative to similar community samples, the frequency of SVD markers in the PREVENT-Dementia cohort was on the higher end [46], which could be attributed to the oversampling of individuals at higher risk of developing dementia, including carriers of the APOE4 allele (38% study frequency vs. 18% in the UK [47]) which is a risk factor of SVD in older adults, despite group differences not reaching statistical significance in our cohort. This evidence concerns the gene APOE and dementia.