Serum adiponectin levels in adolescents and young adults with growth hormone deficiency.

INTRODUCTION: Adiponectin (APN) is adipose tissue-derived hormone influencing energy metabolism. Growth hormone deficiency (GHD) may contribute to the development of disturbances in the hormonal function of adipose tissue (AT), and many disorders observed in untreated patients with GHD coincides with these contributed to low serum APN levels.

OBJECTIVES: The assessment of serum adiponectin levels in adolescents and young adults with severe or partial GHD and analysis of relationships between serum APN and GH/IGF-1 axis function impairment as well as cardiometabolic risk factors.

DESIGN AND SETTING: Based on the results of insulin tolerance test (ITT) patients were qualified for one of the following groups: 1) severe GHD - SGHD (26 patients; 8 women and 18 men); 2) partial GHD - PGHD (22 patients, 7 women and 15 men); 3) normal GH status - NGHS (28 patients, 9 women and 19 men). The fourth examined group consisted of healthy individuals - H (46 participants; 15 women, 31 men). Anthropometric measurements (height, weight, BMI), analysis of body composition and serum glucose, lipids, insulin, IGF-1 and APN assays were performed in all participants.

RESULTS: There were no significant differences in the concentrations of APN between groups. After calculation of the total APN content in extracellular fluids per unit of fat tissue mass (TAPN/FM), these values were significantly lower in the SGHD (p<0.001) and correlated with the degree of impairment of the GH/IGF-1 axis functioning. In patients with GHD positive correlations between APN and serum HDL cholesterol (r=0.39, p<0.05) have been demonstrated. In the subjects with normal GH secretion serum APN correlated positively with serum HDL cholesterol (r=0.28; p<0.05), and negatively with fasting blood glucose (r=-0.31; p<0.05).

CONCLUSIONS: Severe, but not partial growth hormone deficiency impairs adiponectin production in the adipose tissue that is compensated by the increase of fat mass. The degree of GH/IGF-1 axis disruption is related to the TAPN/FM. This parameter may be potentially useful in diagnosing severe growth hormone deficiency in the adults.