There is a reduction in the GH-IGF-1 axis activity with increasing age, but there is evidence that the pool of GH available for release is not diminished in elderly subjects. Furthermore this reduction in GH secretion is not solely responsible for the physical changes associated with ageing. There is a clear distinction between the GH status of normal elderly subjects and elderly subjects with GHD due to hypothalamic-pituitary disease, in whom GH secretion is reduced by more than 90%. GH replacement therapy has proven benefits in elderly subjects with severe GHD, whereas GH treatment in healthy elderly subjects has not been shown to improve functional status, even though considerable improvement in body composition has been observed. GH secretagogues can increase GH levels physiologically, can be taken orally, and have been shown to provide advantageous changes in body composition for up to 2 years, thereby providing some hope that in the future the hyposomatotropism associated with increasing age can be corrected for a worthwhile purpose. Future studies should focus on frail elderly subjects, and aim to determine if their state of independent living can be prolonged by the induction of such changes in GH-IGF-1 status.
06 - 07 Nov 2006
Society for Endocrinology