Malaria Is Associated with Diminished Levels of Ascorbic Acid: A Systematic Review and Meta-Analysis
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
Antioxidants & Redox Signaling
Abstract
Background: It is still unclear how ascorbic acid levels relate to the pathogenesis of malaria. This systematic
review synthesized different ascorbic acid levels in malaria patients with different severity levels of malaria and
Plasmodium species.
Methods: The systematic review protocol was registered in the PROSPERO database (CRD42023394849).
A systematic search of PubMed, Embase, MEDLINE, Ovid, Scopus, and Google Scholar was conducted to
identify studies that reported ascorbic acid and malaria. The pooled standardized mean difference (Cohen’s d)
with 95% confidence intervals (CIs) was calculated using the random-effects model.
Results: A total of 1480 articles were obtained from the searches of the databases, and 30 studies were included
for syntheses. The meta-analysis revealed that patients with malaria had lower levels of ascorbic acid than those
without malaria or uninfected controls ( p < 0.01, Cohen’s d = -3.71, 95% CI = -4.44 to -2.98, I
2 = 98.87%, 30
studies). Comparable levels of ascorbic acid were observed between patients with severe malaria and those with
nonsevere malaria ( p = 0.06, Cohen’s d = -1.39, 95% CI = -2.85 to 0.07, I
2 = 96.58%, 4 studies). Similarly,
levels of ascorbic acid were comparable between patients with Plasmodium falciparum and Plasmodium vivax
malaria ( p = 0.34, Cohen’s d = -1.06, 95% CI = -3.23 to 1.12, I
2 = 97.30%, 3 studies).
Conclusions: The meta-analysis reveals diminished levels of ascorbic acid in malaria cases. Manipulating the
host’s nutritional status, such as by supplementing it with ascorbic acid to restore reactive oxygen species
balance, may alter the progression of malarial infection and prevention of disease severity.
Description
Research Article
Keywords
ascorbic acid, vitamin C, malaria, Plasmodium, systematic review, meta-analysis