APOE and Alzheimer disease: Moreover, the ApoE ε2/ε2 (OR 0.612, 95% CI [0.504–0.743], P < 0.001), ε2/ε3 (OR 0.649, 95% CI [0.585–0.714], P < 0.001) and ε3/ε3 (OR 0.508, 95% CI [0.468–0.551], P < 0.001) genotypes were less frequent in patients with AD than in healthy controls, and the differences were statistically significant.