Deficiência de GH em adultos: resultados do estudo multicêntrico brasileiro

Additional beneficial effects of recombinant growth hormone in alendronate-treated patients with idiopathic osteoporosis

In order to study the benefit of adding recombinant human growth hormone (rhGH) to antiresorptive therapy, six patients with idiopathic osteoporosis (IO) receiving alendronate plus calcium and vitamin D were started on daily subcutaneous injections of rhGH 2.0 IU for one year. Fasting morning urine and serum samples were collected for N telopeptide of type-1 collagen (NTX), serum bone-specific alkaline phosphatase (BSAP) and insulin-like growth factor 1 (IGF-1) during the study. Bone mineral density (BMD) was determined by dual-energy x-ray absorptiometry at baseline and 01 year. The effect of rhGH was evaluated comparing the percentage changes in BMD during the last year on ALN with the results obtained with the combined therapy. Serum IGF-1 increased in all patients but variations were not significant (p=0.266). Serum BSAP did not significantly change (p=0.078) but median NTX increased at 45 days from 12.3 to 19.8 nMBCE/mMCr (p=0.012) and tended to return to baseline values at 12 months (15.2 nMBCE/mMCr). Comparing with isolated ALN therapy, a beneficial effect on bone density was observed in 2/3 of the patients at lumbar spine, and percentage change (median and quartiles) varied from -0.65% (-2.33 and 2.23) on ALN to 0.70% (-0.35 and 3.03) on ALN+GH. Although no bone gain occurred at the femoral neck, our data point to a positive effect of rhGH in patients with idiopathic osteoporosis.

Glucose metabolism and visceral fat in GH deficient adults: two years of GH-replacement

The aim of this study was to evaluate the effect of 24 months of growth hormone (GH) replacement on glucose metabolism and visceral fat in 17 adults with GH deficiency: 9 men and 8 women; age 40 +/- 1.8 yr. [range 20-61] and body mass index 25 +/- 0.8 Kg/m2. Glucose metabolism was evaluated by a standard oral glucose tolerance test (OGTT), by the homeostatic model assessment (HOMA) insulin resistance index and by the insulin sensitivity index (ISI)-composite derived from the OGTT. Visceral fat was evaluated by CT scan.Twenty-four months of GH replacement induced an increase in the prevalence of abnormal glucose tolerance, with significant progressive increment in 2h-OGTT insulin levels at 3, 12 and 24 months (p = 0.005). Plasma glucose levels and ISI-composite did not alter during the study. HOMA-IR index increased only in the group of patients (n = 8) who had abnormal OGTT at 24 months (p = 0.012). Visceral fat reduced at month 12 and remained decreased until the end of the study (p = 0.009). In conclusion, the present study suggests that adults with GH deficiency after twenty-four months of GH replacement developed abnormal glucose tolerance, probably due to an increase in insulin resistance, associated with higher insulin levels, despite favorable alterations in body composition.