Circulating irisin is lower in gestational diabetes mellitus

Irisin is a newly identified myokine. Several studies have reported irisin concentrations in patients with gestational diabetes mellitus (GDM), but because of smaller sample sizes, the data from previous reports showed a wide range in serum/plasma irisin. Therefore, the present investigation is designed to summarize a precise confidence interval of circulating irisin in participants with GDM from a cross-sectional study in Chinese population and a meta-analysis for validation. Serum irisin was tested in patients with GDM and healthy controls (newly diagnosed cases: 61 and matched controls: 61) in the cross-sectional study. The two groups of participants were matched for age and pregnancy duration. Furthermore, we did a comprehensive meta-analysis to confirm whether serum/plasma irisin differs between participants with GDM and controls. Articles reported "circulating irisin and GDM" in Medline, PubMed, and EMBase were obtained, with the key word "myokine" or "irisin". The comparison was analyzed by Review Manager 5.2. In the cross-sectional investigation, serum irisin showed a significant lower level in the GDM patients, compared with that in the control group. In the meta-analysis study, the summarized results of the present 5 studies in which 632 participants were included indicated that there was a lower level irisin of -58.68 ng/mL [95% confidence interval (CI)](-113.42, -3.93, P=0.04) in GDM patients than in the control group. The present cross-sectional investigation and meta-analysis is the first to show significant lower circulating irisin in subjects with GDM.