Cat Acromegaly and Growth Hormone Welfare

Feline acromegaly — caused by excess growth hormone from a pituitary tumour — is an underdiagnosed cause of insulin-resistant diabetes in cats that requires specific treatment for optimal welfare.

Key Facts

Acromegaly affects middle-aged to older male cats predominantly, caused by a functional pituitary somatotroph tumour
Excess GH causes insulin resistance — affected cats develop severe, difficult-to-control diabetes mellitus
Clinical signs include a large head, enlarged paws, spaces developing between teeth, and progressive abdominal enlargement
Most cats with acromegaly are presented for poorly controlled diabetes without the underlying cause being identified
Insulin requirements in acromegalic cats can be enormous — hundreds of units daily — until growth hormone excess is addressed
Definitive treatment with radiation therapy or hypophysectomy can reduce GH levels and dramatically improve diabetic control

Welfare Considerations

Acromegaly causes progressive physical changes and metabolic dysfunction that significantly impairs welfare. Poorly controlled diabetes from insulin resistance causes persistent hyperglycaemia with associated thirst, urination, weight loss, and weakness. Without identifying acromegaly as the underlying cause, escalating insulin doses fail to control glucose and cats continue to suffer. The physical changes — bony enlargement, joint hypertrophy — may cause discomfort. Definitive treatment through radiation therapy or surgery dramatically improves diabetic control and may achieve remission, transforming welfare outcomes. The welfare case for investigating the underlying cause of insulin resistance in diabetic cats is strong — simple IGF-1 blood testing screens for acromegaly efficiently.

What You Can Do

Request IGF-1 testing in any diabetic cat requiring escalating insulin doses that fail to achieve adequate glucose control
Discuss radiation therapy or hypophysectomy referral with a specialist if acromegaly is confirmed — definitive treatment dramatically improves outcomes
Monitor quality of life carefully for acromegalic cats — signs of discomfort from physical changes require pain management assessment
Ensure adequate diabetic monitoring during treatment transition — insulin requirements change as GH levels fall post-treatment