Differential effects of growth hormone therapy in malnourished hemodialysis patients

Background. Malnutrition is common in chronic hemodialysis patients and is associated with increased morbidity and mortality. Several factors such as metabolic acidosis, hyperparathyroid ism. and insulin as well as growth hor mone (GH) resistance may lead to enhanced protein catabolism. Recombinant h uman growth hormone (rhGH) has been proposed as treatment of malnutrition b ecause of its anabolic effects. Methods. In the present placebo-controlled. double blind study, the effects of three months of rhGH therapy on nutritional and anthropometric paramete rs, on bone metabolism and bone mineral density (BMD), as well as on polymo rphonuclear leukocyte (PMNL) function and quality of life (QoL) were evalua ted in 19 malnourished hemodialysis patients (10 females and 9 males) with a mean age of 59.3 +/- 13.4 years. RhGH (0.125 IU/kg) was given three times a week during the first four weeks and 0.25 IU/kg thereafter three times a week after each dialysis session. Results, Insulin-like growth factor I (IGF-I) concentration rose significan tly from 169.2 +/- 95.6 ng/mL to 262.9 +/- 144.4 ng/mL (p < 0.01) in the gr oup receiving rhGH. Albumin, prealbumin. transferrin. cholesterol. high-den sity lipoprotein (HDL) cholesterol, cholinesterase. predialytic creatinine. and blood urea nitrogen showed no significant changes during the three mon ths in both groups. Total body fat (%TBF) was slightly reduced after three months (P = NS) in the patients receiving GH, whereas lean body mass LMM) r emained stable during therapy. Procollagen I carboxy terminal peptide (PICP ), a marker of bone formation, increased significantly after three months f rom 250.1 +/- 112.6 to 478.5 +/- 235.2 mug/L (P < 0.01) in the GH-treated p atients, whereas parameters of bone resorption like telopeptide ICTP showed only a slight increase (50.3 +/- 18.5 vs. 70.0 +/- 39.5 mug/L, P = NS). BM D at the lumbar spine decreased significantly after three months in the tre atment group (0.8 +/- 0.17 vs. 0.77 +/- 0.16 g/cm(2), p < 0.01), whereas BM D at the femoral neck remained stable in both groups. Phagocytic activity o f PMNLs increased significantly after three months of therapy with rhGH, wh ereas other parameters of PMNL function were not affected by GH. QoL was sl ightly improved in the GH treated group, but decreased markedly in the plac ebo group. Conclusions. Three months of treatment with rhGH in malnourished patients o n chronic hemodialysis causes a significant increase in IGF-I levels withou t significant changes in nutritional and anthropometric parameters. In cont rast, bone turnover was enhanced with an initial decrease in BMD at the lum bar spine, and phagocytic activity of PMNLs was increased.