Growth Hormone (GH) Effects on Central Fat Accumulation in Adult Japanese GH Deficient Patients: 6-month Fixed-dose Effects Persist during Second 6-month Individualized-dose Phase

Abstract

Abstract. Both Japanese and Caucasian adults with GH deficiency (GHD) have pronounced abdominal obesity, which is associated with increased risk of cardiovascular complications. We investigated the effects of GH treatment in 27 adult Japanese GHD patients, 15 with adult onset (AO) and 12 with childhood onset (CO) GHD. Patients initially received GH titrated to 0.012 mg/kg/day for 24 weeks in a double-blind design and the dose was then individualized for each patient according to IGF-I for a further 24 weeks. Dual-energy x-ray absorptiometry (DXA) data were evaluated for percentages of trunk fat, total body fat and lean body mass. Serum IGF-I and lipid concentrations were determined at a central laboratory. There were 25 patients who completed 48 weeks of treatment, with 7, 6 and 12 patients then receiving GH at 0.003, 0.006 and 0.012 mg/kg/day, respectively. With the reductions in dose when individualized between weeks 24 and 48, mean serum IGF-I level was reduced and excessively high values, observed in AO patients on the fixed GH dose, were no longer seen. The decrease from baseline in trunk fat was similar at week 24 (-3.8 ± 3.3%, p<0.001) and week 48 (-3.1 ± 3.7%, p<0.001), and the difference between changes was not significant. Total cholesterol was decreased from baseline by -24 ± 28 mg/dl (p<0.001) at week 24 and -17 ± 28 mg/dl (p = 0.007) at week 48. Two patients had elevated HbA1c levels: one continued GH treatment after a dose reduction and the other discontinued due to persistent impaired glucose tolerance. Therefore, excessively high IGF-I levels can be avoided by individualized dosing during long-term GH treatment. Individualized dosing maintains the decrease in abdominal fat in adult Japanese GHD patients and should reduce the cardiovascular risk.

Calcium Tablets Reduce Osteoporosis Risk Factors and Increase Insulin‐like Growth Factor‐1 in Teenage Girls

“…Abnormal central fat accumulation was recently reported to be reduced by growth hormone treatment, which would result in cardiovascular risk reduction at the optimal dose. 10 In conclusion, our study found that the intake of Ca supplement (300 mg/day), together with 100 mg magnesium, 0.9 mg vitamin D3 and 19 mg vitamin K, could increase BMC and IGF-1, and tended to decrease BF, although there were no changes in BMI and LB, in teenage girls. This dose of Ca taken daily at a young age could beneficially affect growth hormone secretion and hopefully contribute to the risk reduction of prospective osteoporosis by increasing peak bone mass.…”

“…Therefore, increased Ca results in osteoblastic proliferation that promotes further IGF‐1 secretion. Abnormal central fat accumulation was recently reported to be reduced by growth hormone treatment, which would result in cardiovascular risk reduction at the optimal dose 10 …”