Impact of malaria on glutathione peroxidase levels: a systematic review and meta-analysis

The primary antioxidant, glutathione peroxidase (GPx), is hypothesized to contribute to the pathophysiology of malaria. This current study conducted a meta-analysis to examine variations in GPx blood levels in malaria patients. Seven electronic databases—ProQuest, Scopus, Embase, MEDLINE, PubMed, Ovid, and Google Scholar—were searched for relevant studies with no limitations to publication language or publication date. The Joanna Briggs Institute critical appraisal tools were used to appraise the risk of bias among the included studies critically. The meta-analysis was conducted by pooling the effect estimates and Hedges’s g using a random-effects model. Search results returned 1253 articles, of which 16 studies were used for syntheses. Results of the meta-analysis indicated that malaria patients had decreased blood levels of GPx compared to uninfected individuals (P < 0.01, Hedges’ g: − 4.06, 95% CI − 5.49–(− 2.63), I(2): 99.07%, 1278 malaria patients/627 uninfected individuals, 15 studies). Subgroup analyses indicated that peripheral levels of GPx were significantly diminished in patients with P. falciparum malaria compared to uninfected controls (P < 0.01, Hedges’ g: − 3.06, 95% CI − 4.46–(− 1.65), I(2): 98.39%, 9 studies) but not in patients with P. vivax malaria (P = 0.15, Hedges’ g: − 2.05, 95% CI − 4.83–0.74), I(2): 98.64%, 2 studies) Overall, malaria is associated with declined levels of GPx, particularly in patients with P. falciparum malaria. The finding provides valuable insights that prompt the need to investigate the role of GPx depletion in malaria pathogenesis.