Background: Regulation of leptin in different populations has still not been fully understood and the role of different modulators seems to have ethnic variation. Aim The present study was designed to investigate the association of various anthropometric, and biochemical variables with leptinemic status in type 2 diabetes mellitus. 
Materials and methods: Fifty-seven (57) T2DM cases with age and BMI matched 61 non diabetic healthy controls [(years, 36±4 in diabetic vs. 36±4 in controls, M±SD) and (kg/m2, 23.8±1.9 vs. 23.6±2.8)] were included in this cross-sectional study. Anthropometric parameters were assessed by standard methods. Fat mass was measured by bioelectric impedance analysis. Fasting serum glucose was measured by glucose oxidase method. Plasma insulin and leptin were estimated by Enzyme Immunoassay. Insulin secretory capacity (HOMA-B%) and insulin sensitivity (HOMA-S%) were calculated by Homeostasis Model Assessment using HOMA-CIGMA software. 
Results: Fasting serum leptin level was significantly higher in both control and diabetic females compared to those of males [ng/ml, median (range), Control: 23.2(4.7-55.0) vs. 4.55(1.36-21), p<0.001; T2DM: 11.3(3.2-35) vs. 3.07(0.65-7.5), p<0.001]. Serum leptin level was significantly lower in diabetic subjects compared to controls (32.5% less in male diabetic, p=0.007; 51% less in female diabetic; p=0.002, respectively). Moreover, fat normalized leptin was also significantly lower in diabetic subjects compared to controls (p<0.05). Diabetic subjects showed highly significant β-cell dysfunction (HOMA B%) compared to controls both in male and female (male, p<0.001 & female, p<0.001 respectively]. Insulin sensitivity (HOMA S%) showed significant difference only in female subjects (p<0.012). In multiple regression analysis serum fat normalized leptin was associated with sex (β=-0.581, p<0.001), diabetes (β=-0.251, p<0.001), subscapular (β=0.132, p=0.033), fasting insulin (β=0.300, p<0.001) when the effects of other confounding factors are adjusted. After covariate adjustment for sex, diabetes, WHR, subscapular and HOMA%S, fat normalized leptin remained a significant correlation with HOMA%B (β=0.269, p=0.013). 
Discussion: The data suggest that, 1) sex is strongly associated with serum leptin concentration, 2) T2DM induced hypoleptinemia is independent of fat mass and is associated with insulin secretory dysfunction, and 3) peripheral obesity is a major determinant of leptinemic status.

Association of anthropometric and biochemical parameters with leptin in Bangladeshi type 2 diabetes mellitus