• Adult GHD can be a result of adult or childhood onset, and may occur as an isolated GH deficiency or as part of a multiple pituitary hormone deficiency.
• ​​​​​​​Several possible aetiologies may underlie GHD.
  

• Childhood-onset GHD is often idiopathic, and may continue into adult life.
• Iatrogenic GHD may also occur in survivors of childhood malignancy as a result of previous cranial irradiation or chemotherapy​​​​.
  

The Society for Endocrinology estimates that approximately 1 in 10,000 adults in the UK population will develop adult onset GHD¹.

Adult patients who are commonly tested for GHD include:

1) Those with signs and symptoms of hypothalamic–pituitary disease (endocrine, structural, and/or genetic causes)^{2
​​​​​​​}2) Those who have received cranial irradiation or tumor treatment²
3) Those with traumatic brain injury or subarachnoid haemorrhage²

• A reduced quality of life and reduced energy levels ^1,3,4
• Altered body composition with increased fat mass around the trunk along with dyslipidaemia and hypertension are likely to contribute to increased cardiovascular mortality in GHD ^1,3
• Reduced bone mineral density, with increased risks of osteopenia and osteoporosis^1,5.  There is 2-5 fold increased risk of fractures in adults with GHD vs. non GHD deficient populations ⁵
• Reduced exercise capacity and a reduction in muscle strength ^1,6,7,8
• Increased cardiovascular risk as a result of
  • Increased thickness of the intima media of blood vessels¹
  • Increased levels of fibrinogen and plasminogen activator inhibitor¹
    
  • ^{​​​​​​​}Lipid abnormalities, especially elevated LDL cholesterol¹
    
  • ^{​​​​​​​}Insulin resistance¹
    
  • Impaired cardiac function¹