Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2024 Jan 18;25(2):1168.
doi: 10.3390/ijms25021168.

Salivary Biomarkers for Alzheimer's Disease: A Systematic Review with Meta-Analysis

Kacper Nijakowski  1 , Wojciech Owecki  2 , Jakub Jankowski  2 , Anna Surdacka  1
Affiliations
Meta-Analysis

Salivary Biomarkers for Alzheimer's Disease: A Systematic Review with Meta-Analysis

Kacper Nijakowski et al. Int J Mol Sci. .

Abstract

Alzheimer's Disease (AD) is the most common neurodegenerative disease which manifests with progressive cognitive impairment, leading to dementia. Considering the noninvasive collection of saliva, we designed the systematic review to answer the question "Are salivary biomarkers reliable for the diagnosis of Alzheimer's Disease?" Following the inclusion and exclusion criteria, 30 studies were included in this systematic review (according to the PRISMA statement guidelines). Potential biomarkers include mainly proteins, metabolites and even miRNAs. Based on meta-analysis, in AD patients, salivary levels of beta-amyloid42 and p-tau levels were significantly increased, and t-tau and lactoferrin were decreased at borderline statistical significance. However, according to pooled AUC, lactoferrin and beta-amyloid42 showed a significant predictive value for salivary-based AD diagnosis. In conclusion, potential markers such as beta-amyloid42, tau and lactoferrin can be detected in the saliva of AD patients, which could reliably support the early diagnosis of this neurodegenerative disease.

Keywords: Alzheimer’s Disease; beta-amyloid; biomarkers; lactoferrin; neurodegenerative diseases; saliva; tau.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Quality assessment, including the main potential risk of bias (risk level: green—low, yellow—unspecified, red—high; quality score: green—good, yellow—intermediate, red—poor) [26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55].
Figure 2
Figure 2
PRISMA flow diagram presenting search strategy.
Figure 3
Figure 3
Standardised mean difference of beta-amyloid42 levels in saliva from patients with Alzheimer’s Disease compared to healthy subjects [27,28,30,31,35,37,38].
Figure 4
Figure 4
Standardised mean difference of total tau levels in saliva from patients with Alzheimer’s Disease compared to healthy subjects [26,30,33,37].
Figure 5
Figure 5
Standardised mean difference of phosphorylated tau levels in saliva from patients with Alzheimer’s Disease compared to healthy subjects [31,33,35,37].
Figure 6
Figure 6
Standardised mean difference of lactoferrin levels in saliva from patients with Alzheimer’s Disease compared to healthy subjects [38,39,40,41].
See this image and copyright information in PMC

References

    1. Guo T., Zhang D., Zeng Y., Huang T.Y., Xu H., Zhao Y. Molecular and Cellular Mechanisms Underlying the Pathogenesis of Alzheimer’s Disease. Mol. Neurodegener. 2020;15:40. doi: 10.1186/s13024-020-00391-7. - DOI - PMC - PubMed
    1. Zhang X.-X., Tian Y., Wang Z.-T., Ma Y.-H., Tan L., Yu J.-T. The Epidemiology of Alzheimer’s Disease Modifiable Risk Factors and Prevention. J. Prev. Alzheimers Dis. 2021;8:313–321. doi: 10.14283/jpad.2021.15. - DOI - PubMed
    1. Porsteinsson A.P., Isaacson R.S., Knox S., Sabbagh M.N., Rubino I. Diagnosis of Early Alzheimer’s Disease: Clinical Practice in 2021. J. Prev. Alzheimers Dis. 2021;8:371–386. doi: 10.14283/jpad.2021.23. - DOI - PubMed
    1. Lane C.A., Hardy J., Schott J.M. Alzheimer’s Disease. Eur. J. Neurol. 2018;25:59–70. doi: 10.1111/ene.13439. - DOI - PubMed
    1. Guzman-Martinez L., Calfío C., Farias G.A., Vilches C., Prieto R., Maccioni R.B. New Frontiers in the Prevention, Diagnosis, and Treatment of Alzheimer’s Disease. J. Alzheimers Dis. 2021;82:S51–S63. doi: 10.3233/JAD-201059. - DOI - PubMed