The level of serum NEAT1 in mild and moderate to severe AD patients was higher than that in the control group, and the level of serum NEAT1 in moderate to severe AD patients was higher than that in mild AD patients (P < 0.05); The level of serum miR-27a-3p was lower than that of the control group, and the level of moderate to severe AD patients was lower than that of mild AD patients (P < 0.05), as shown in Table 2. Here, NEAT1 is linked to Alzheimer disease.