INSULIN ANTAGONISTIC EFFECTS OF GROWTH-HORMONE IN SHORT CHILDREN

Growth hormone has several insulin antgonistic effects. To determine t he time course of these effects in growth-hormone-treated children, th e frequently sampled intravenous glucose tolerance test was used to me asure insulin sensitivity (S-I) and glucose effectiveness (S-g) before , and 1 week, 1 month and 6 months after beginning growth hormone ther apy in 3 patients with growth hormone deficiency (GHD), 3 patients wit h non-growth-hormone-deficient short stature (NGHD) and 3 with Turner syndrome (TS). Pretreatment S-I was lower in TS than in the other two groups (p < 0.05), but S-g did not differ between groups. Mean S-I lev els 1 week and 1 month after starting growth hormone therapy were not different from before growth hormone [1.67 +/- 0.26 x 10(-4) (pmol/l)( -1) min(-1)]. S-I after 6 months of growth hormone [0.67 +/- 0.15 x 10 (-4)(pmol/l)(-1) min(-1)] was lower than before and 1 week after growt h hormone (p < 0.005). S-I responses did not differ between groups. S- g, glucose tolerance, blood pressure, triglyceride, and cholesterol le vels did not change, but the incremental insulin response increased wi th growth hormone therapy. Thus, in this small study 6 months of growt h hormone therapy decreased S-I, but did not affect other cardiovascul ar risk factors.