Affiliations: [a]
Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| [b]
National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, China
| [c]
Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
| [d] Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
| [e] Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
Correspondence:
[*]
Correspondence to: Dr. Bin Jiao, Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya Road, Kaifu District, Changsha, 410008, China. Tel.: +86 13548984561; E-mail: 4011070@csu.edu.cn.
Abstract: Background:Several studies have shown increased levels of cerebrospinal fluid (CSF) synaptosomal-associated protein 25 (SNAP-25) in patients with Alzheimer’s disease (AD). However, results have been inconsistent thus far. Objective:We conducted meta-analyses summarizing the associations of CSF SNAP-25 levels with AD to assess the utility of SNAP-25 as a novel biomarker for AD. Methods:We conducted a meta-analysis of differences in CSF SNAP-25 levels in patients with AD or mild cognitive impairment (MCI) and in cognitively healthy controls (HC). We calculated pooled correlation coefficients comparing SNAP-25 levels and total tau (T-tau) or hyperphosphorylated tau (P-tau) in CSF. Results:Eight studies enrolling 1,162 individuals (423 AD, 275 MCI, 464 HC) were included for quantitative analysis. Patients with AD (ratio of means [RoM] = 1.50, 95% confidence interval [CI]: 1.30,1.74) and MCI (RoM = 1.45, 95% CI: 1.12,1.87) had increased levels of CSF SNAP-25 as compared to HC. The difference in CSF SNAP-25 levels when comparing AD and MCI (RoM = 1.05, 95% CI: 0.96,1.14) was not statistically significant but showed a trend toward significance. Statistically significant correlations were found when comparing CSF SNAP-25 with CSF T-tau (Spearman correlation coefficient, ρ=0.78; ρ=0.66; ρ=0.69, respectively) and P-tau (ρ=0.77; ρ=0.70; ρ=0.62, respectively) levels in patients with AD, MCI, and HC. Conclusion:Increased CSF SNAP-25 levels differentiated patients with AD or MCI from controls, suggesting the utility of this biomarker in the early diagnosis of AD.
