Leptin and cardiometabolic risk factors in obese children and adolescents.

AIM: To verify the relationship between leptin and cardiometabolic risk factors in obese children and adolescents.
METHODS: A cross-sectional study evaluated 200 children and adolescents treated in Campina Grande, Brazil, from April 2009 to March 2010. Leptin, fasting glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides were determined. The t-test was used to compare leptin means of two groups and analysis of variance to compare means of three groups. Multiple comparisons of pairs of group means were performed with Tukey's test. In all tests, a significance level of 0.05 was adopted.
RESULTS: The leptin sample mean was 22.7 ± 10.0 μg/L (95% confidence interval: 21.3 μg/L to 24.1 μg/L). Leptin was significantly higher in the following groups: female, teenager, increased waist circumference, high systolic blood pressure, elevated triglycerides hyperinsulinemia, insulin resistance and metabolic syndrome. Most cardiometabolic risk factors had higher means in the last quartile of leptin, except total-cholesterol, LDL-C and triglycerides levels. HDL-C was reduced in the last quartile of leptin. Simple linear regression analysis showed a significant negative correlation between leptin and HDL-C and a positive correlation between leptin and triglycerides, insulin, HOMA-IR, body mass index, waist circumference, and systolic and diastolic blood pressure. Multiple linear regression models showed an independent association between leptin and HDL-C, triglycerides, insulin, HOMA-IR, body mass index, waist circumference, systolic and diastolic blood pressure, after age and gender control.
CONCLUSION: Leptin may be a useful marker of metabolic syndrome and insulin resistance in obese adolescents.