Association between serum copeptin levels and preeclampsia risk: A meta-analysis

The role of vasopressin in preeclampsia pathogenesis has been recently supported by experimental studies. This meta-analysis aims to accumulate literature evidence and evaluate whether serum copeptin levels differ among preeclamptic and healthy pregnant women. Medline, Scopus, CENTRAL, Web of Science and Google Scholar databases were systematically searched from inception. All observational studies reporting serum copeptin values among preeclamptic and healthy pregnant women were deemed eligible. Sixteen studies were included, comprising 2105 women. Preeclampsia was linked to significantly higher copeptin levels during the 1st (Standardized Mean Difference-SMD: 2.25, 95% Confidence Intervals-CI: 0.86-3.67), 2nd (SMD: 1.73, 95% CI: 0.31-3.14) and 3rd (SMD: 1.74, 95% CI: 0.96-2.53) trimester. This association was present for severe, non-severe, early and late-onset preeclampsia. Women with the severe form of the disease displayed significantly elevated copeptin levels (SMD: 1.47, 95% CI: 1.10-1.84) compared to those with the non-severe one, while no difference was evident between early and late-onset preeclampsia (SMD: -0.30, 95% CI: -0.91 to 0.31). In conclusion, the present meta-analysis suggests that preeclampsia is associated with significantly increased serum copeptin levels in all pregnancy trimesters, irrespective of disease severity and onset. Future large-scale cohort studies should confirm these findings and introduce cut-off values in order to clarify the exact accuracy of copeptin for the prediction of preeclampsia early in the course of pregnancy.