Unwanted effects of growth hormone excess in the adult.

This review discusses in vitro, animal and human studies which provide insights into the deleterious effects of excess GH and IGF-I. The systemic sequelae of hypersomatotrophism include disorders of the cardiovascular, respiratory and rheumatologic systems. Impaired carbohydrate metabolism and an increased incidence of gastrointestinal malignancy also contribute to morbidity and an average 10 year reduction in mortality. Major determinants of these sequelae appear to include both the magnitude and duration of hypersomatotrophism. Extrapolation of these findings to adults receiving replacement or pharmacologic doses of GH requires longer term controlled studies.