After adjusting for BMI, levels of education, history of malignant tumor, habit of salt intake, ischemic stroke, diabetes, hypertension, and dyslipidemia in the logistic regression, 14 initial glycans (increased relative abundance of GP1, GP2, GP5, GP7, GP8, GP9, GP10, GP12, GP13, GP15, and GP22 as well as reduced relative abundance of GP14, GP16, and GP18) remained significantly different between dementia and NC groups (p < 0.05; q < 0.05) (Table 3 and Supplementary Fig. 1). The gene discussed is GP9; the disease is diabetes mellitus.