Correlations of skinfold thicknesses and circumferences at exactly defined body sites with leptin in 10-12-year-old boys with different BMIs.

The aim of this study was to investigate the correlations of leptin with values of skinfold thicknesses and circumferences in 10-12-year-old boys (N = 248) and these correlations were additionally studied in boys with different BMI subgroups (normal N = 190, overweight N = 34 and obese N = 24). In total, 9 skinfolds and 13 circumferences were measured using the recommendations of ISAK. Fasting leptin concentrations were also determined. No significant differences emerged between the three subgroups in age and Tanner stage. Skinfold thicknesses, circumferences and leptin concentrations were significantly higher in overweight and obese groups. In the total group, the correlation (partial correlation, eliminating age and Tanner stage) between separate skinfold thicknesses and leptin was higher than r = 0.70. The sum of 9 skinfold thicknesses correlated significantly to leptin in all groups (r = 0.558-0.779). In the obese group, triceps, biceps and front thigh skinfold thicknesses did not correlate (p > 0.05) with leptin. In the total group, all measured circumferences correlated significantly to leptin concentration (r = 0.328-0.724). However, in the obese group, the measured circumferences did not correlate to leptin (p > 0.05). Waist-to-hip ratio correlated with leptin only in the total group of boys. It was concluded that as a rule, close correlations emerged between leptin and skinfold thicknesses and circumferences. The strongest correlation with leptin was found with the sum of 9 skinfolds and waist-to-hip ratio.