RESUMO
BACKGROUND: Growth hormone (GH) treatment in short children born small for gestational age (SGA) may result in metabolic changes with potential long-term effects. METHODS: 149 short SGA children (mean birth weight 2.0 ± 0.6 kg, age 5.5 ± 1.5 years, height standard deviation score (SDS) -3.1 ± 0.6) were randomised to: low-dose GH therapy (0.033 mg/kg/day) for 2 years; high-dose GH therapy (0.100 mg/kg/day) for 1 year, or mid-dose GH therapy (0.067 mg/kg/day) for 1 year. Leptin, ghrelin, insulin-like growth factor-I (IGF-I), IGF binding protein-1 (IGFBP-1), lipids, fasting blood glucose and fasting insulin were assessed at baseline, 12 and 24 months. RESULTS: After 1 year of active treatment, GH significantly reduced serum ghrelin and increased IGF-I SDS and insulin levels. Regression analysis showed an inverse correlation between ghrelin and IGF-I SDS (p < 0.001). Leptin and IGFBP-1 also declined (both p < 0.05). Changes in insulin levels reversed upon discontinuation. Improvements in lipid profile were nonsignificant and fasting blood glucose levels remained within the normal range. CONCLUSION: In short SGA children, ghrelin and leptin reductions associated with GH treatment may occur through a negative feedback loop of the GH-IGF-I axis. Consequently, via ghrelin and leptin suppression, GH treatment may modify food intake and body composition and potentially improve long-term metabolic outcomes.
Assuntos
Hormônio do Crescimento Humano/administração & dosagem , Recém-Nascido Pequeno para a Idade Gestacional/metabolismo , Estatura/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Seguimentos , Grelina/metabolismo , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Recém-Nascido , Insulina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/metabolismo , MasculinoRESUMO
BACKGROUND: The most effective growth hormone (GH) treatment regimen for increasing height in short children born small for gestational age (SGA) has not been well defined. METHODS: Short SGA children (n = 151, age 3-8 years, height less than -2.5 standard deviation scores) were randomised to receive low-dose GH for 2 years (0.033/0.033 mg/kg/day, n = 51), high-dose GH for 1 year and then no treatment for 1 year (0.100/0 mg/kg/day, n = 51) or were untreated for 1 year then received mid-dose GH for 1 year (0/0.067 mg/kg/day, n = 47). Height, bone age and adverse events were determined at check-ups every 3 months. RESULTS: The mean +/- SD additional height gain with GH after 1 year, relative to untreated controls, was higher with discontinuous high-dose than with continuous low-dose GH (6.5 +/- 0.2 vs. 3.3 +/- 0.2 cm). After 2 years, the additional height gain was similar between high- and low-dose GH groups (between-group treatment difference = 0.2, 95% CI = -0.8 to 1.2 cm, p = 0.702). Patients treated exclusively in the last year had a similar height gain to those in the other treatment groups (p = 0.604). CONCLUSIONS: In short SGA children, continuous low-dose and discontinuous high-dose GH regimens were associated with similar height gain. Treatment with mid-dose GH for 1 year also led to a similar improvement in growth.