AUTHOR=Hamid Maryam , Mansoor Sumaiya , Amber Sanila , Zahid Saadia 

TITLE=A quantitative meta-analysis of vitamin C in the pathophysiology of Alzheimer’s disease

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=14

YEAR=2022

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2022.970263

DOI=10.3389/fnagi.2022.970263

ISSN=1663-4365

ABSTRACT=<sec><title>Purpose</title><p>Alzheimer’s disease (AD) is a multifaceted neurodegenerative disorder with many complex pathways feeding into its pathogenesis and progression. Vitamin C, an essential dietary antioxidant, is vital for proper neurological development and maintenance. This meta-analysis and systematic review attempted to define the relationship between vitamin C plasma levels and AD while highlighting the importance and involvement of vitamin C in the pathogenesis of AD.</p></sec><sec><title>Materials and methods</title><p>PRISMA guidelines were used to obtain studies quantifying the plasma levels of vitamin C in AD and control subjects. The literature was searched in the online databases PubMed, Google Scholar, and Web of Science. A total of 12 studies were included (<italic>n</italic> = 1,100) and analyzed using Comprehensive Meta-Analysis 3.0.</p></sec><sec><title>Results</title><p>The results show that there is a significant decrease in the plasma vitamin C levels of AD patients as compared to healthy controls (pooled SMD with random-effect model: −1.164, with 95%CI: −1.720 to −0.608, <italic>Z</italic> = −4.102, <italic>p</italic> = 0.00) with significant heterogeneity (<italic>I</italic><sup>2</sup> = 93.218). The sensitivity analysis showed directionally similar results. Egger’s regression test (<italic>p</italic> = 0.11) and visual inspection of the funnel plot showed no publication bias.</p></sec><sec><title>Conclusion</title><p>Based on these studies, it can be deduced that the deficiency of vitamin C is involved in disease progression and supplementation is a plausible preventive and treatment strategy. However, clinical studies are warranted to elucidate its exact mechanistic role in AD pathophysiology and prevention.</p></sec>