IGF1 and acromegaly: Acromegaly results from an excess secretion of GH from a pituitary adenoma leading to an increase in IGF-1 concentrations.1,2 The symptoms are due to the effects of both GH and IGF-1 on cartilage, soft tissues and organs, such as the heart, and the compression of the surrounding tissues by the tumour itself, which results in headache, visual field defects and hypopituitarism.1,2 Patients with active acromegaly have an elevated morbidity and mortality that correlate with the elevated plasma levels of GH and IGF-1.3,4