Causes
Excess levels of the hormone cortisol are responsible for Cushing syndrome. Cortisol, which is produced in the adrenal glands, plays a variety of roles in your body.
For example, cortisol helps regulate your blood pressure, reduces inflammation, and keeps your heart and blood vessels functioning normally. Cortisol helps your body respond to stress. It also regulates the way you convert (metabolize) proteins, carbohydrates and fats in your diet into usable energy.
However, when the level of cortisol is too high in your body, you may develop Cushing syndrome.
Body Own overproduction
The condition may also be due to your body's own overproduction of cortisol (endogenous Cushing syndrome). This may occur from excess production by one or both adrenal glands, or overproduction of the adrenocorticotropic hormone (ACTH), which normally regulates cortisol production.
Complications
Without treatment, complications of Cushing syndrome may include:
Bone loss (osteoporosis), which can result in unusual bone fractures, such as rib fractures and fractures of the bones in the feet
High blood pressure (hypertension)
Type 2 diabetes
Frequent or unusual infections
Loss of muscle mass and strength