Study on insulin resistance in the etiopathology of gestational diabetes mellitus

Objective To investigate the relationship between fasting serum leptin and insulin resistance and the role of insulin resistance in the etiopathology of gestational diabetes mellitus(GDM).Methods Fasting serum leptin,C-peptide and insulin at 0 h and 2 h of 75g oral glucose tolerance test(OGTT)were measured by radioimmunoassay in 32 patients with GDM and 30 normal glucose tolerance(NGT)pregnant controls.Insulin secretion was assessed by the homeostasis β-cell function index(HBCI),insulin resistance by the homeostasis model insulin resistance index(HOMA-IR).Results ① HOMA-IR was higher in GDM groups than in NGT groups[(2.3±0.3) vs.(1.4±0.4),P0.01].No significant difference of HBCI between the two groups was observed (P0.05).② Serum leptin was higher in women with GDM than in pregnant women with NGT [(24.7±2.2)ng/ml vs.(20.3±1.5)ng/ml,P0.05].Serum leptin was positively correlated with HOMA-IR in GDM group(rGDM=0.578,P0.001),but was not correlated with HOMA-IR in NGT group(rNGT=0.221,P0.05).Conclusions Insulin resistance may be one of the major cause of GDM.Leptin is closely associated with insulin resistance in GDM and may play important role in genesis of GDM.