Effects of recombinant human growth hormone on protein turnover in the fasting and fed state in adolescents with Crohn disease.

The primary purpose of this study was to test whether recombinant human growth hormone (rhGH) supplementation would enhance protein synthesis and accretion of lean body mass. Eight adolescents (six males and two females; 17.2 +/- 2.6 years; age range, 13.7-21.2 years) participated in a randomized double-blind placebo-controlled cross-over trial of rhGH. We employed stable isotopes to measure proteolysis and protein synthesis during fasting and fed conditions during two 6-month treatment conditions. We also measured bone mineral density (BMD), markers of bone turnover, and body composition. Whole-body proteolysis, phenylalanine catabolism, and protein synthesis did not differ during treatment with rhGH vs. placebo. Enteral nutrition suppressed proteolysis and increased protein synthesis similarly during placebo and rhGH treatments. We conclude that rhGH is unlikely to provide sufficient metabolic benefit to warrant its use as an adjunct treatment in clinically stable adolescents with Crohn disease. A high prevalence of vitamin D deficiency and suboptimal BMD existed, which deserves further investigation and clinical attention.