Circulating apelin, chemerin and omentin levels in patients with gestational diabetes mellitus: a systematic review and meta-analysis

Background The available data on the significance of circulating apelin, chemerin and omentin in women with gestational diabetes mellitus (GDM) are inconsistent. This analysis includes a systematic review of the evidence associating the serum concentrations of these adipokines with GDM. Methods Publications through December 2019 were retrieved from PubMed, Embase, the Cochrane Library, and Web of Science. Subgroup analysis and meta-regression were conducted to evaluate sources of heterogeneity. Results Analysis of 20 studies, including 1493 GDM patients and 1488 normal pregnant women did not find significant differences in circulating apelin and chemerin levels (apelin standardized mean difference [SMD] = 0.43, 95% confidence interval (CI): - 0.40 to 1.26, P = 0.31; chemerin SMD = 0.77, 95% CI - 0.07 to 1.61, P = 0.07). Circulating omentin was significantly lower in women with GDM than in healthy controls (SMD = - 0.72, 95% CI - 1.26 to - 0.19, P = 0.007). Publication bias was not found; sensitivity analysis confirmed the robustness of the pooled results. Conclusions Circulating omentin was decreased in GDM patients, but apelin and chemerin levels were not changed. The results suggest that omentin has potential as a novel biomarker for the prediction and early diagnosis of GDM.