AUTHOR=Chen Fan , Wang Na , Tian Xinyan , Qin Yan , Su Juan , He Rongqiao , He Xiaping TITLE=The potential diagnostic accuracy of urine formaldehyde levels in Alzheimer’s disease: A systematic review and meta-analysis JOURNAL=Frontiers in Aging Neuroscience VOLUME=Volume 14 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2022.1057059 DOI=10.3389/fnagi.2022.1057059 ISSN=1663-4365 ABSTRACT=Background: Formaldehyde (FA), as a toxic aldehyde, has been shown to be associated with a variety of cognitive disorders including Alzheimer's disease (AD). And there is increasing evidence that FA levels are significantly increased in AD patients and may be involved in the pathological process of AD. The aim of this study was to assess the potential diagnostic value of urine FA levels for AD using meta-analysis techniques. Methods: Original reports of morning urine FA levels in AD patients and healthy controls were included for meta-analysis. Standardized mean differences were calculated using a random-effects model, heterogeneity was explored using methodological, age, and sensitivity analyses, and ROC curves were constructed to assess the diagnostic value of urine FA levels in AD. Results: A total of 12 studies were combined and urine FA levels were reviewed in 874 AD patients and 577 healthy controls (HC). Compared with HC, FA levels were significantly increased in AD patients. The heterogeneity of the results did not affect the robustness of themselves, and the AUC area suggested that urine FA levels had a good diagnostic potential. Conclusion: Urine FA levels are involved in AD progression and are likely to be used as a potential biomarker for clinical auxiliary diagnosis, but due to limitations, further studies are needed to validate the results of this study.