Cushing's Syndrome
Cushing's syndrome is a condition caused by having too much cortisol in the body for a long time.
Overview
Cushing's syndrome is a condition caused by having too much cortisol in the body for a long time. Cortisol is a hormone made by the adrenal glands that helps the body respond to stress, control blood pressure and manage blood sugar. The most common cause is taking steroid medicines (glucocorticoids) at high doses or for a long time. Less commonly, the body makes too much cortisol (called endogenous Cushing's syndrome). When cortisol levels stay high, it can affect many parts of the body, including weight, skin, muscles, bones, mood and the heart and blood vessels.
Causes and Genetics
Cushing's syndrome may be caused by steroid medicines (for example tablets, injections, inhalers or creams) which act like cortisol in the body; a pituitary gland tumour producing too much ACTH (called Cushing's disease); an adrenal gland tumour making cortisol; or rarely, a tumour elsewhere in the body making ACTH (ectopic ACTH syndrome). Most cases are not inherited. Rare genetic conditions can increase the risk of hormone-producing tumours, but this is uncommon.
Symptoms and Features
Symptoms often develop gradually and can be mistaken for more common conditions. Not everyone has all features.
Characteristic Symptoms and Features
- Weight gain (especially around the tummy and upper back)
- Rounded face
- Thinning of the arms and legs
- Muscle weakness and tiredness
- High blood pressure
- High blood sugar or diabetes
- Mood changes and sleep problems
Other Associated Symptoms and Features
- Easy bruising, acne, slow wound healing and wide purple stretch marks (often on the tummy, thighs or arms)
- In women, periods may become irregular and there may be increased facial or body hair
- In children, growth may slow down
- If untreated, increased risk of infections, osteoporosis (thin bones), blood clots and heart problems
Treatment
Supportive care may include treatment for high blood pressure and diabetes, blood clot prevention in higher-risk situations, bone protection, infection prevention, and mental health support. Long-term follow-up is important because symptoms may take time to improve after cortisol levels are controlled, and some people need hormone replacement treatment. Patients are usually managed through specialist endocrine centres.
Research and Future Directions
Research is focused on improving earlier diagnosis, refining testing pathways, and developing more targeted treatments to control cortisol with fewer side effects. International expert statements and guidelines are also regularly updated to improve care, including guidance on diagnosis, monitoring, and medical treatments.