relationship between leptin and insulin resistance in Iranian obese children

Leptin is an adipocyte- derived hormone that plays an important role in the pathogenesis of obesity. Obesity is associated with insulin resistance and hyperinsulinemia. Insulin resistance is one of the factors which have been suggested to affect leptin serum levels. There are few studies evaluating the relation between leptin level and insulin resistance in childhood and adolescence obesity. The aim of the present study is to investigate this relationship in Iranian obese children. We screened 13089 primary school students aged 7-12 years. Children were divided to overweight and normal based on the recently published National Center for Health Statistics growth charts. The number of children which were overweight was 498, of whom 347 subjects particiated in the study. Fasting blood glucose, insulin and leptin levels were measured and homeostasis model assessment [HOMA] of insulin resistance [HOMA-IR] and fasting glucose to insulin ratio [FGIR] were calculated and compared between two groups. Serum leptin levels were significantly higher in overweight compared to normal group. [11.58 +/- 8.1 and 8.1 +/- 5.2 respectively p<0.05]. Before adjustment for BMI, there was a significant correlation between leptin and fasting insulin, HOMA -IR index and FGIR. [r=0.1, p< 0.05, r=0.1, p<0.01, r=0.07, p<0.05 respectively]. After adjustment for BMI, no significant correlation was found [r=0.097, p=0.20]. The relation between leptin and insulin resistance was weak and disappeared after adjustment for BMI. It seems that many other factors including BMI and total fat amount may affect this relationship. Further studies in this field are required

[Obesity and associated cardiovascular risk factors in Iranian children]

Background: obesity is a serious public health problem in developing countries due to its association with the cardiovascular risk factors. Childhood obesity is responsible for a number of different complications both during childhood and adulthood. The aim of the present study was to determine the cardiovascular risk factors in overweight and obese Iranian children

Methods: we screened 13086 children aged 7-12 years by measuring waist circumference. Those with a waist circumference 261 cm were selected for further evaluation. Antjfropometric measurements were'done and blood samples were taken from 563 enrolled ovenveightlobese children [284 boys and 279 girls]. We determined cardiovascular risk factors [including fasting total cholesterol, LDL-C, HDL-C, triglycerides, blood pressure]. In addition we measured the fasting blood .sugar, insulin, apo-A , apo-B and leptin levels

Results: only 2.7% of overweight or obese children had no risk factors. While, 20.6% had one and 70.85% had two or more risk factors. The prevalence of high total Cholestrol levels was 42.6%. HDLC showed an acceptable level in 92.4%of children .There were strong correlations between BMI and serum apoB and leptin levels [p<0.005]

Conclusion: the high prevalence of cardiovascular risk factors in overweight and obese Iranian children emphasizes the need for prevention and control of childhood obesity from early childhood in our country