Short-term effects of recombinant human growth hormone in CAPD patients

Abstract

Protein and calorie malnutrition is common in chronic dialysis patients. Several interventions have been proposed to prevent and/or to treat malnutrition. Recombinant human growth hormone (rhGH) is a drug with anabolic properties and has been used in several catabolic conditions, such as patients with severe burns as well as in pediatric patients with chronic real failure. In this study, we evaluated the short-term effects and safety of rhGH on urea kinetics and commonly measured biochemical parameters in 10 stable adult continuous ambulatory peritoneal dialysis (CAPD) patients. The design of the study was prospective, cross-over with the patients serving as their own controls. There were three study periods: baseline (PreGH), treatment (Tx), and follow-up (PostGH). During the seven day Tx period, patients self-administered 5 mg/day s.c. of rhGH. During this time, there was a significant decrease in blood urea nitrogen (BUN) (54 ± 15 to 40 ± 12 mg/dl), as well as in the combined dialysate and urine nitrogen excretion rates (5.69 ± 1.86 to 4.04 ± 1.13 g/day), and protein catabolic rate (0.82 ± 0.13 to 0.67 ± 0.09 g/kg/day), (all P < 0.001). Serum phosphorus (4.8 ± 1.6 to 4.4 ± 1.8 mg/dl) and potassium (4.0 ± 0.4 to 3.6 ± 0.2 mEq/liter) levels also showed a small but statistically significant decrease in conjunction with a statistically significant increase in serum creatinine levels (12.2 ± 5.7 to 12.9 ± 5.7 mg/dl). Dietary protein intake, determined by dietary recall, did not change during the study (66.1 ± 20.5 vs. 75.8 ± 22.1 grams/day). Serum glucose (155 ± 98 to 213 ± 129 mg/dl) and insulin-like growth factor 1 (193 ± 74 to 662 ± 261 ng/ml) levels increased significantly with rhGH treatment. All laboratory values returned to baseline by the end of the PostGH period. No changes were noted in dialysate protein losses, daily creatinine excretion, serum transferrin, or prealbumin levels. No clinically evident adverse side effects were noted. We conclude that short-term administration of rhGH to stable CAPD patients is associated with a net decrease in total urea nitrogen appearance, evidenced by a decrease in concentrations of BUN and daily urea nitrogen excretion, and is consistent with the anabolic effects of rhGH. Long-term studies are needed to define the steady-state effects of the rhGH in chronic dialyis patients.