What endocrine disorder is caused by chronic overproduction of cortisol?

Cushing's syndrome is characterized by chronic overproduction of cortisol, which is a steroid hormone produced by the adrenal glands. When cortisol levels are elevated for extended periods, it can lead to a variety of physiological effects and symptoms, including weight gain, particularly around the abdomen and face, thinning skin, easy bruising, hypertension, and osteoporosis. The condition can result from various causes, such as an adrenal tumor, pituitary adenoma secreting adrenocorticotropic hormone (ACTH), or ectopic ACTH production from other tumors.

Understanding the other options provides context for why they do not fit the description of chronic cortisol overproduction. Addison's disease, for example, is characterized by insufficient cortisol production due to adrenal insufficiency. Hypopituitarism involves a deficiency in one or more of the pituitary hormones, which does not correlate with excess cortisol. Hyperthyroidism relates to an overproduction of thyroid hormone, not cortisol. Therefore, Cushing's syndrome is the correct choice when identifying the disorder associated with chronic overproduction of cortisol.