CD34 and dementia: Among them, only CD34+CD133+ EPCs, but none of the other cell types, significantly impacted the risk of AD (HR = 0.64, P = 0.02) and all-cause dementia (HR = 0.63, P = 0.006) after adjusting for age, sex, years of education, APOE ε4, and vascular diseases (Table 1).