In the codominant model, subjects carrying the TT allele of ApoE rs7412 had a 3.112 times higher risk of cognitive impairment than subjects with the CC genotype (OR = 3.112 (1.159–8.359), P = 0.024), and subjects carrying the AA allele of ApoE rs7259620 had a 1.588 times higher risk of cognitive impairment than subjects with the GG genotype (OR = 1.588 (1.007–2.504), P = 0.047). This evidence concerns the gene APOE and Cognitive impairment.