Assessing the Possible Association between Polymorphism of C677T MTHFR with Preeclampsia Risk: A Systematic Review and Bayesian Hierarchical Meta-Analysis

Abstract

Objectives: Preeclampsia (PE) is a pregnancy-related disorder with an incidence of 2-5% that causes the death of 40,000 women worldwide each year. Among different accepted etiologies, hyperhomocysteinemia has been shown to be a key player in the progression of PE. Considering the solid role of methylenetetrahydrofolate reductase (MTHFR) in the metabolism of homocysteine, genetic polymorphism of MTHFR that could affect its activity may trigger the risk of PE. This hierarchical Bayesian metaanalysis aimed to assess the possible association between C677T MTHFR polymorphism and the risk of PE.
 Methods: In this study, PubMed, Scopus, and Web of Science databases were searched from 2000 until 2019 to evaluate the association of MTHFR C677T polymorphism with the risk of PE in relevant case-control studies. The relevant studies were included regardless of population ethnicity and geographical limitation. The extracted data were statistically analyzed using a hierarchical Bayesian method and the association strength was estimated by log (OR) with a 95% credible interval.
 Results: Thirty-three studies with 3930 cases and 5236 controls met our inclusion criteria. The pooled results indicated no significant effect of MTHFR C677T (C>T) on PE risk under allelic (log(OR) = 0.09, 95% CI = -0.02, 0.204), homozygous (log(OR) = 0.173, 95% CI = -0.027, 0.378), heterozygous (log(OR) = -0.009, 95% CI = -0.123, 0.104), dominant (log(OR) = 0.009, 95% CI = -0.109, 0.133), and recessive (log(OR) = 0.173, 95% CI = -0.012, 0.366) models.
 Conclusion: It can be concluded that MTHFR C677T polymorphism had no significant effect on the risk of PE.