The levels of SUVR, NEAT1 and BACE1 in cerebrospinal fluid of AD patients in mild group and moderate to severe group were higher than those in the control group, and the levels of AD patients in moderate to severe group were higher than those in mild group (P < 0.05); Cerebrospinal fluid miR-27a-3p, Aβ 42 level and Aβ 42/ Aβ 40 ratio were lower than that of the control group, and the AD patients in the moderate to severe group were lower than those in the mild group (all P < 0.05), as shown in Table 3. Here, BACE1 is linked to Alzheimer disease.