Increase of serum lipoprotein (a) levels during growth hormone therapy in normal short children

We studied the effect of growth hormone (GH) therapy on serum lipoprotein levels and the atherogenic index in short children without GH deficiency. Fasting blood samples were collected from ten (eight males) normal, short, prepubertal children, aged 6-12 years, before, during a 1- year course of GH therapy (0.1 IU/Kg/day), and 3 months after the cessation of GH administration. An increase in serum lipoprotein(a) [Lp(a)] levels of (mean% ± SEM) 43 ± 14, 58 ± 18, 61 ± 17 above the baseline levels was noted at 3 months (P < 0.05), 6 months (P < 0.01), and 1-year (P < 0.01) respectively after the beginning of GH administration. (ANOVA, P < 0.01). An inverse relationship between baseline serum Lp(a) concentrations and the percentage increment in Lp(a) after 9 months of GH therapy (r = -0.65, P < 0.05) was observed. GH therapy over a period of 1 year had no effect on plasma cholesterol, triglycerides, low density lipoprotein-cholesterol (LDL- C), high density lipoprotein cholesterol [HDL-C] concentrations and the atherogenic index. Three months after the cessation of GH therapy, serum Lp(a) levels were not significantly different from the pre-treatment values. Conclusions: Serum Lp(a) concentrations remained above pretreatment values during a 1-year period of GH treatment in short children without GH deficiency and declined shortly after cessation of therapy. Since GH therapy for short children without GH deficiency usually continues for several years, we suggest that serum Lp(a) levels should be determined and followed regularly in such children under prolonged GH therapy.