APOE and Alzheimer disease: Of interest, although a substantial polymorphic iron-allele burden seems do not affect the MMSE in the whole group (MMSE: 21.0, 17.4–24.4 versus 21.4, 18.5–23.7; P = 0.27) as well as in subgroups (AD: P = 0.098; VaD: P = 0.44; MCI: P = 0.45), the APOE4 significantly worsened the median MMSE of the whole group only in the presence of an elevated iron allele-burden (P = 0.006) with respect to the opposite genetic counterpart (P = 0.38).