776 Impaired GH Secretion Corrolates with Increased Visceral Adiposity and Hyperinsulinemia in HAART-treated Children A. Vigano*1, S. Mora2, P. Brambilla1, L. Monti2, L. Schneider1, P. Manzoni1 1Paediatric Clin L Sacco Hosp, Milan, Italy and 2IRCCS Hosp San Raffaele, Milan, Italy
Background: Impaired GH secretion has been described in HIV-infected adults with lipodystrophy, characterized by excess accumulation of visceral fat. A lipodystrophy syndrome with the same feature occurs in HAART-treated HIV-infected children. GH physiology has not been assessed in paediatrics.
Methods: Twenty-five (25) pubertal HAART-treated children were assessed for growth hormone (GH) secretion after arginine + GHRH stimulation test. Fasting serum insulin-like growth factor-1 (IGF-1), IGF binding protein 3 (IGFBP3), insulin, cholesterol (total, HDL, LDL), triglycerides, and nitric oxide levels were also determined. Total and regional body composition was evaluated by dual X-ray-photon-absorptiometry; intrabdominal adipose tissue content (IAT) was assessed by magnetic resonance imaging (MRI). An increased visceral adiposity was defined as an IAT > 41 cm2. Differences between subjects with (V+) and without (V-) increased visceral adiposity were assessed by non-parametric tests and multivariate analysis; relationships between metabolic and body composition parameters were evaluated by Spearman test.
Results: Ten (10) V+ (mean IAT 82.5 cm2) and 15 V- (mean IAT 26.1 cm2) children were identified. Age (14.8 vs 13.8 yrs), BMI (19.3 vs 20.2), female/male ratio (7/8 vs 7/3), months of HAART exposure (55.5 vs 54.5) were not different in the 2 groups. V+ children showed lower GH area under the curve (AUC, 16.4 vs 31.6 mcg/hr/l; p < 0.05), IGF-1 (384 vs 515 ng/ml, p < 0.05), IGFBP3 (4.3 vs 4.7 mcg/ml, p < 0.05), nitric oxide (11.5 vs 27.9 mmol/l, p < 0.05) and higher insulinemia (17.8 vs 9.8 mcIU/ml, p < 0.05) than V- children. Lipid profile was similar in the 2 groups. V+ children, as compared to V- children, showed increased fat mass (11.0 vs 6.8 kg, p < 0.005), trunk fat (6.6 vs 3.7 kg, p < 0.0001) and fat/lean ratio (0.31 vs 0.17, p < 0.001). GH-AUC negatively correlated with IAT (rho = 0.36) and insulinemia (rho = 0.48).
Conclusions: Impaired GH secretion is detectable in pubertal HAART-treated children with increased visceral adiposity and hyperinsulinemia. The monitoring of GH secretion could be included in the evaluation of HIV-associated lipodystrophy in children. Recombinant GH therapy should be considered in HIV-infected children with excess IAT.
