Serum NEAT1 level in AD patients was positively correlated with SUVR, cerebrospinal fluid NEAT1 and BACE1 (r = 0.350, 0.606, 0.341, all P < 0.05);serum miR-27a-3p level was positively correlated with cerebrospinal fluid miR-27a-3p level (r = 0.695, P < 0.05), and negatively correlated with SUVR and cerebrospinal fluid BACE1 level (r = − 0.521, − 0.447, both P < 0.05). Here, BACE1 is linked to Alzheimer disease.