Purpose: To assess the association of serum leptin and its receptor (SLeptinR) with the risk of gestational diabetes mellitus (GDM) and to evaluate the longitudinal circulation of these peptides in pregnancy.
Methods: This study consisted of 53 subjects diagnosed with GDM and 43 normal glucose tolerance (NGT) pregnant women. Serum leptin and SLeptinR were measured at 24-28 weeks, prior and after delivery, and post-puerperium.
Results: Lower levels of leptin and SLeptinR were observed in GDM compared to NGT. Leptin [OR 0.97 (95% CI 0.94-1.0)] and SLeptinR [OR 0.86 (95% CI 0.79-0.93]) were inversely associated with GDM. Participants in the lowest tertile for leptin and SLeptinR had a 2.8-fold (95% CI 1.0-7.6) and a 5.7-fold (95% CI 1.9-17.3) higher risk of developing GDM compared with the highest tertile, respectively. These relationships were attenuated after adjustment for covariates. In both the groups, peak leptin was observed at 24-28 weeks, decreasing continuously during pregnancy (p > 0.05) and after delivery (p < 0.017). SLeptinR level increased (p < 0.001) during pregnancy and decreased (p < 0.005) after delivery in GDM, however, levels remained the same in NGT. In GDM, leptin and SLeptinR was positively and inversely correlated with BMI and HOMA-IR at 24-28 weeks and post-puerperium, respectively. The cord levels of both leptin and SLeptinR were lower than maternal levels. There were no significant differences in serum cord leptin and SLeptinR levels between the groups.
Conclusion: Leptin and SLeptinR are independently and inversely associated with GDM. Lower levels of these peptides may play an important role in the pathophysiology of GDM and pre-diabetic state in post-puerperium.
Keywords: Gestational diabetes (GDM); Leptin; Soluble leptin receptor (SLeptinR).