Logistic regression analysis adjusted for the apolipoprotein E polymorphism showed that in AD patients with delusions the presence of an 5-HTTLPR-S allele may reduce disease duration (p = 0.005; OR = 0.680, 95% CI = 0.522–0.886) and increase aberrant motor activity (p = 0.013; OR = 2.257, 95% CI = 1.195–4.260). Here, APOE is linked to Alzheimer disease.