Logistic regression models assessed associations between standardized index scores and all-cause dementia and Alzheimer's disease (AD) across age group (<65 vs. ≥65 years), sex, and APOE4 status.<h4>Results</h4>During the mean follow-up of 10.6 (9.3-12.3) years (SD=0.74), all indices significantly predicted dementia and AD, though none outperformed the demographics-only model. This evidence concerns the gene APOE and early-onset autosomal dominant Alzheimer disease.