ANABOLIC THERAPY WITH GROWTH-HORMONE ACCELERATES PROTEIN GAIN IN SURGICAL PATIENTS REQUIRING NUTRITIONAL REHABILITATION

Objective The authors investigated the effects of exogenous growth hor mone (GH) on protein accretion and the composition of weight gain in a group of stable, nutritionally compromised postoperative patients rec eiving standard hypercaloric nutritional therapy. Summary Background D ata A significant loss of body protein impairs normal physiologic func tions and is associated with increased postoperative complications and prolonged hospitalization. Previous studies have demonstrated that st andard methods of nutritional support enhance the deposition of fat an d extracellular water but are ineffective in repleting body protein. M ethods Fourteen patients requiring long-term nutritional support for s evere gastrointestinal dysfunction received standard nutritional thera py (STD) providing approximately 50 kcal/kg/day and 2 g of protein/kg/ day during an initial 7-day equilibrium period. The patients then cont inued on STD (n = 4) or, in addition, received GH 0.14 mg/kg/day (n = 10). On day 7 of the equilibrium period and again after 3 weeks of tre atment, the components of body weight were determined; these included body fat, mineral content, lean (nonfat and nonmineral-containing tiss ue) mass, total body water, extracellular water (ECW), and body protei n. Daily and cumulative nutrient balance and substrate oxidation studi es determined the distribution, efficiency, and utilization of calorie s for protein. fat, and carbohydrate deposition. Results The GH-treate d patients gained minimal body fat but had significantly more lean mas s (4.311 +/- 0.6 kg vs. 1.988 +/- 0.2 kg, p less-than-or-equal-to 0.03 ) and more protein (1.417 +/- 0.3 kg vs. 0.086 +/- 0.1 kg, p less-than -or-equal-to 0.03) than did the STD-treated patients. The increase in lean mass was not associated with an inappropriate expansion of ECW. I n contrast, patients receiving STD therapy tended to deposit a greater proportion of body weight as ECW and significantly more fat than did GH-treated patients (1.004 +/- 0.3 kg vs. 0.129 +/- 0.2 kg, p < 0.05). GH administration altered substrate oxidation (respiratory quotient = 0.94 +/- 0.02 GH vs. 1.17 +/- 0.05 STD, p less-than-or-equal-to 0.000 2) and the use of available energy, resulting in a 66% increase in the efficiency of protein deposition (13.37 +/- 0.8 g/1000 kcal vs. 8.04 g +/- 3.06 g/1000 kcal, p less-than-or-equal-to 0.04). Conclusions GH administration accelerated protein gain in stable adult patients recei ving aggressive nutritional therapy without a significant increase in body fat or a disproportionate expansion of ECW. GH therapy accelerate d nutritional repletion and, therefore, may shorten the convalescence of the malnourished patient requiring a major surgical procedure.