Growth Hormone Effects on the Adult Skeleton

Abstract

Recent years have seen considerable progress in our understanding of the normal processes by which peak adult bone mass is acquired and maintained, the physical, nutritional, and hormonal factors that regulate bone mass throughout adult life, and the critical role of reproductive hormonal replacement for maintaining bone mass within the early years after menopause. During this same period a number of therapeutic agents have been shown to minimize bone loss and confer protection against osteoporotic fracture. Almost exclusively, these agents act to reduce the rate of bone resorption. Each shows significant positive effects on bone mass, and estrogen, in particular, exerts a profound influence on fracture risk, but none of these agents restores bone mineral of osteopenic patients to normal levels. To date, the goal of achieving major increases in bone mass remains an elusive and formidable research challenge. At the recent Serono Symposium on Growth Hormone, I presented results from a clinical trial of recombinant human growth hormone (rhGH) in healthy elderly women. This chapter expands those remarks to discuss the skeletal effects of GH in adults that have provoked considerable interest in the use of this agent as a potential treatment for osteoporosis.