Similar trends were observed in individuals with AD and other bacterial intestinal infections (including APOE t-test = −2.31, P = 2.24e-02; excluding APOE t-test = −2.26, P = 2.54e-02), other disorders of pancreatic internal secretion (including APOE t-test = −2.17, P = 3.12e-02), oesophagitis (including APOE t-test = −3.08, P = 2.33e-02; excluding APOE t-test = −2.39, P = 1.78e-02), as well as gastritis and duodenitis (including APOE t-test = −2.83, P = 4.76e-03). Here, APOE is linked to bacterial infectious disease.