What Is Cushing's?

Cushing's syndrome, also known as hypercortisolism or hyperadrenocorticism, is an endocrine disorder caused by prolonged exposure of the body's tissues to high levels of the hormone cortisol (in the blood) from a variety of causes, including primary pituitary adenoma (known as Cushing's disease), primary adrenal hyperplasia or neoplasia, ectopic ACTH production (e.g., from a small cell lung cancer), and iatrogenic (steroid use). It is relatively rare and most commonly affects adults aged 20 to 50. An estimated 10 to 15 of every million people are affected each year. Cushing's was discovered by American physician, surgeon and endocrinologist Harvey Cushing (1869-1939) and reported by him in 1932.

Normally, cortisol is released from the adrenal glands in response to ACTH being released from the pituitary gland. Both Cushing's syndrome and Cushing's disease are characterized by elevated levels of cortisol in the blood, but the cause of elevated cortisol differs between the two.