What happens when growth hormone is discontinued at completion of growth? Metabolic aspects

Continuing growth hormone (GH) replacement therapy in patients with childho od-onset GH deficiency (GHD) that persists into adulthood is an emerging is sue. The prospective, long-term metabolic consequences of discontinuing GH therapy in adolescent patients with childhood-onset GHD and short stature h ave only recently been reported. These studies demonstrate that serum conce ntrations of total cholesterol, low-density lipoprotein-cholesterol and apo lipoprotein B are higher in adolescents in whom severe GHD continues into a dulthood. Upon discontinuation of GH therapy, serum concentrations of high- density lipoprotein-cholesterol have been found to decrease in patients wit h severe GBD and increase in patients regarded as GH sufficient when retest ed for GHD. Furthermore, total body fat and truncal fat mass increase after discontinuation of GH in both these patient groups, but more markedly in t he patients with severe GHD, In adolescents with severe CHD persisting into adulthood, the discontinuation of GH therapy produces, over a period of 2 years, the accumulation of important cardiovascular risk factors that are a ssociated with GHD in adults. Continuing replacement therapy into adulthood should therefore be considered.