Objectives: To observe the evolution of intraabdominal adipose tissue (IAT) in obese prepubertal children, who did not change their degree of obesity during adolescence and to evaluate its relationship with metabolic risk indexes (RI).
Design: Longitudinal study of 16 obese adolescents (eight male and eight female) in whom relative body weight (RBW) did not change significantly and pubertal development was completed during the study period.
Measurements: Magnetic resonance imaging (MRI) scan at lumbar level (L4) three times during a 4 y period. At basal and at four years biochemical assays for metabolic indexes.
Results: IAT did not differ significantly over the three measurement times and showed significant correlations between first and second (r = 0.66, P < 0.005), first and third (r = 0.61, P < 0.01) and second and third values (r = 0.84, P < 0.0001). Subcutaneous adipose tissue (SAT) increased significantly from basal to third evaluation (P < 0.002). At baseline, IAT correlated significantly with lipids (total and LDL cholesterol r = 0.72, P < 0.004), while at the end of the study, IAT correlated positively with insulin (fasting insulin r = 0.55, P < 0.008, insulin area after oral glucose tolerance test (OGTT) r = 0.60, P < 0.03, fasting insulin/glucose r = 0.67 P < 0.006) and negatively with high density lipoprotein (HDL) cholesterol (r = -0.55, P < 0.04).
Conclusions: Obesity achieved before puberty, and stable during adolescence, showed a relatively stable amount of IAT. In post pubertal children the relationship of IAT to clinically significant risk factors resemble the pattern in obese adults.