Recombinant human growth hormone enhances the metabolic efficacy of parenteral nutrition: a double-blind, randomized controlled study

Abstract

This multicenter, randomized, double-blind study was performed to investigate whether recombinant GH improves the efficacy of total parenteral nutrition (TPN). Fifteen stable patients requiring parenteral feeding due to gastrointestinal/pancreatic disease were studied. Constant maintenance TPN providing approximately 30 kcal/kg day and approximately 1.6 g protein/kg.day was administered during an initial 7-day baseline period. After randomization, daily sc injections of saline (control, n = 9) or GH (10 mg/day, n = 6) were administered a 14-day treatment period as nutrient intake remained constant. Elemental balances for nitrogen (N), potassium (K), phosphorus (P), and sodium (Na) were determined daily and serial blood indices, vital signs, and other clinical parameters were monitored. Nutrient balances approached equilibrium during the baseline week in both groups. With GH administration, a significant increase in N, K, and P balance occurred; in contrast, nutrient balances did not change significantly from baseline values in control patients. The cumulative change (delta) in nutrient balances from the baseline week was also significantly greater in the GH-treated patients (delta N: control+2 +/- 7 g vs. GH+36 +/- 6. g, P less than 0.005; delta K:+57 +/- 45 mmol vs.+199 +/- 19 mmol, P less than 0.03; delta P: -27 +/- 30 mmol vs. +91 +/- 69 mmol, P less than 0.02). Plasma insulin-like growth factor-I concentrations rose 5-fold and serum cholesterol rose slightly with GH; no other significant change in group mean blood values occurred. One patient receiving GH and chronic prednisone therapy developed moderate hyperglycemia and mild peripheral edema; no other deleterious effects attributable to GH were observed. GH was well tolerated and significantly enhanced nutrient retention compared to standard parenteral feeding alone. GH improves the efficacy of parenteral nutrient utilization in patients requiring TPN.