A Study On Relationship Between Leptin And IGT And Type 2 Diabetes Mellitus

Objective To examine the relationship between human serum leptin levels and indices of obesity, glucose and insulin levels as well as lipid profile, and exploring pathway to prevent type 2 diabetes mellitus. Methods Fasting leptin levels ,glucose, insulin,and lipid profile were measured in 180 subjects (including 40 type 2 DM, 100 IGT, 40 NGT; 88 men, 92 women),and oral glucose tolerance test was done in every subject to measure 2-h glucose and insulin levels. Serum leptin and insulin were measured by means of RIA. Glucose and lipid profile were measured by means of auto-analysis apparatus. Height, body weight, waist and hip circumference were measured to calculate body mass index (BMI) and waist to hip ratio (WHR). Insulin resistance index was assessed by HOMA. Results Fasting serum leptin levels were positively correlated with BMI (men r=0.45, P<0.05; women r=0.55, P<0.05), waist circumference (men r=0.40, P<0.05; women r=0.38, P<0.05), fasting insulin (men r=0.35, P<0.05; women r=0.37, P<0.05) and 2-h insulin(men r=0.38, P<0.05; women r=0.40, P<0.05) levels. Leptin levels were 3 times higher in female than in male (p<0.001). All subjects were divided into six groups according to gender and glucose tolerance status. In female subgroups, fasting serum leptin levels were negatively correlated with fasting glucose levels, and fasting leptin levels were significant lower in women with IGT or DM than in women with NGT. In male subgroups, fasting leptin levels were positively correlated with insulin resistance index, but no between-group leptin levels difference was observed. Conclusion Fasting leptin levels were significance lower in women with IGT or DM than in women with NGT. Fasting leptin levels were positively correlated with insulin resistance index only in male subgroups.