GH deficiency (GHD) has implications throughout the lifespan. In childhood, reduced linear growth is the primary consequence of untreated GHD, while in adulthood, untreated GHD is associated with a number of abnormalities. The phenotype of GHD in adulthood differs depending on timing of onset. Childhood onset (CO) patients have reduced bone mineral content (BMC) and lean body mass (LBM) despite GH replacement therapy (GHRT) during childhood compared with adult onset. These differences suggest the CO GHD phenotype is developmental. It is these developmental deficits that have lead to a focus on GHRT in patients with CO GHD in the transition period, spanning from the completion of puberty into young adulthood. The aim of GHRT during this time is to normalise body composition and cardiovascular health with the long-term aim of reducing the morbidity and mortality observed in patients with hypopituitarism.
There is evidence that GHRT at this time aids to reduce this deficit in muscle and bone. This may have the effect of improving physical performance and reducing fractures later in life, however, the epidemiological evidence is currently lacking. There is also inconsistent evidence that cardiovascular risk is increased and QoL is reduced and that these improve with GHRT. It is possible, and there is some evidence to support this, that certain patient groups may demonstrate a worsening cardiovascular risk profile and QoL after a more sustained period of time off GHRT. More studies are required to provide the endocrinologist and the patient with adequate information to inform treatment decisions.
It is essential that paediatric and adult endocrinologists address a young persons wider healthcare needs, including actively encouraging independence and decision making. They should work together with young people and their families to ensure that transition between services is seamless so that they continue to engage with health care whether they opt for GHRT or not.
03 - 05 Nov 2010
British Society for Paediatric Endocrinology and Diabetes