APOE and Alzheimer disease: Statistically significant predictors of AD were age (HR for 10 year increase 3.56, p < .001), age squared (HR for 10 year increase 0.97, p = .006, less than high school education (HR = 1.70, p = 0.007), and APOE-e4 (HR 2.61, p < .001 for one or two copies).