Relationships between leptin and gender, obesity indices, cardiovascular risk factors, and diet in Korean adolescents

Park, Hye Soon; Kim, Young Sik; Sung, Mi Kyung; Seung, Chung Ja

Abstract

BACKGROUND
Obesity in adolescents has been shown to be significantly associated with long term mortality and morbidity. Leptin secreted by adipose tissue regulates body weight, and obese people show high leptin levels as well as leptin resistance. The objective of this study was to examine the relationships of leptin concentration with various indices of obesity, cardiovascular risk factors, and diet in adolescents.
METHODS
We conducted cross sectional study with sixty eight obese (28 male and 40 female) and 80 normal weight adolescents (40 male and 40 female), aged 12 18y, from an urban area in South Korea. Weight, height, body fat, waist and hip circumference, blood pressure, and fasting serum glucose, total, LDL, and HDL cholesterol, triglyceride, and leptin were measured, and a 24 dietary recall obtained.
RESULTS
Females had, on average, two times higher leptin concentrations per fat mass than males. Circulating leptin was strongly associated with body fat (male:r=0.69, p<0.01; female:r=0.67, p<0.01), and waist circumference (male:r=0.65, p<0.01; female:r=0.64, p<0.01). The correlations between log.leptin and some cardiovascular risk factors were weakly positive. None of the association between log.leptin and nutrient intakes were significant. In a multiple regression model, body fat, gender, and waist circumference were found to be significant independent determinants of leptin concentration.
CONCLUSIONS
These results show that female adolescents have higher leptin levels compared to male adolescents, independent of the concomitant variation in total body fat mass. Although leptin concentration did not have direct association with diet intakes, there was significant correlations with obesity indices and several cardiovascualr risk factors in Korean adolescents.