Objective To evaluate value of combined detection of cerebrospinal fluid synaptosomal-associated protein 25 (SNAP-25) and long non-coding RNA nuclear-enriched transcript 1 (NEAT1) in assessing cognitive impairment severity and disease progression in patients with Alzheimer′s disease.

Methods A total of 650 patients with Alzheimer′s disease were selected as research subjects and divided into normal group (n=162), mild cognitive impairment group (n=380) and dementia group (n=108) according to their cognitive function. The correlations of the levels of SNAP-25 and NEAT1 in cerebrospinal fluid with the scores of Mini-Mental State Examination (MMSE) and Clinical Dementia Rating Scale (CDR) were analyzed. According to whether the patients in the mild cognitive impairment group progressed to dementia (followed up for 6 months), they were divided into disease progression group (progressed to dementia) and stable disease group (did not progress to dementia). The levels of SNAP-25 and NEAT1 in cerebrospinal fluid of patients in each group were compared. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of cerebrospinal fluid SNAP-25 combined with NEAT1 for dementia and its predictive efficacy for the progression of mild cognitive impairment to dementia.

Results The levels of SNAP-25 and NEAT1 mRNA in cerebrospinal fluid in the mild cognitive impairment group and the dementia group were significantly higher than those in the normal group; the levels of cerebrospinal fluid SNAP-25 and NEAT1 mRNA in the dementia group were significantly higher than those in the mild cognitive impairment group (P < 0.05). The levels of cerebrospinal fluid SNAP-25 and NEAT1 mRNA in patients of the mild cognitive impairment group and the dementia group were negatively correlated with the MMSE score (P < 0.05), and positively correlated with the CDR score (P < 0.05). In the mild cognitive impairment group, 133 patients′ conditions progressed from mild cognitive impairment to dementia. The levels of cerebrospinal fluid SNAP-25 and NEAT1 mRNA in the disease progression group were significantly higher than those in the stable disease group (P < 0.05). ROC curve analysis showed that the sensitivity of cerebrospinal fluid SNAP-25 combined with NEAT1 in diagnosing dementia was 89.63%, the specificity was 54.08%, and the area under the curve (AUC) was 0.884. The sensitivity of cerebrospinal fluid SNAP-25 combined with NEAT1 in predicting the progression of mild cognitive impairment to dementia was 83.41%, the specificity was 56.70%, and the AUC was 0.867.

Conclusion The levels of SNAP-25 and NEAT1 in cerebrospinal fluid increase significantly with the aggravation of cognitive impairment in patients with Alzheimer′s disease. The combined detection of SNAP-25 and NEAT1 has relatively high diagnostic efficacy for dementia and predictive value for the progression from mild cognitive impairment to dementia.