What Is Cushing’s Syndrome?

Cushing’s syndrome, also called hypercortisolism, is a hormonal disorder caused by excess levels of cortisol. Often known as the “stress hormone,” cortisol plays a role in regulating your blood sugar, blood pressure, metabolism, and inflammation levels. It’s produced by the adrenal glands, which are just above your kidneys. 

Common symptoms of Cushing’s syndrome include easy bruising, changes in fat distribution, and a round face. If left untreated, it can lead to various complications, such as high cholesterol, high blood pressure, and heart disease.

A healthcare provider can diagnose and treat Cushing's syndrome. They can also discuss your risk for developing the condition.

Cushing's Syndrome Symptoms

There are many possible symptoms associated with Cushing’s syndrome. These tend to get worse as the disorder continues.

Some of the most common symptoms include a round, full face, sometimes called "moon face," and weight gain or changes in fat distribution. A person with Cushing's syndrome might have thin limbs and carry excess weight around the stomach, or have a lump on the back between the shoulders.

If you have extremely high levels of cortisol, you may also notice:

• Easy bruising
• Purple stretch marks on the stomach, arms, thighs, or breasts
• Muscle weakness
• Bone pain or tenderness
• Backache
• Fatigue
• Mental health or behavioral changes, such as mood swings and depression
• Headache
• Increased thirst
• Frequent urination

In children, Cushing’s syndrome may also cause slower or delayed growth. Women with Cushing’s syndrome sometimes notice irregular periods and excess hair on the face and body. Some men with the disorder develop sexual dysfunction, such as reduced libido and an inability to sustain an erection.

What Causes Cushing's Syndrome?

Cushing’s syndrome is most commonly caused by the long-term use of corticosteroids, such as prednisone (Rayos). These medicines, which act similarly to cortisol, are usually prescribed to treat chronic inflammatory conditions like lupus or asthma.

More rarely, some people develop the disorder when their body produces too much cortisol on its own. This is known as endogenous Cushing’s syndrome. Causes of endogenous Cushing’s syndrome may include:

• Pituitary tumors
• Adrenal tumors 
• Certain kinds of lung cancers
• Inherited endocrine disorders

Risk Factors

Anyone can develop Cushing’s syndrome, including children. However, it is more common in adults ages 30-50, and especially in women. Other risk factors for the disorder include:

• Long-term steroid use
• Type 2 diabetes
• Very high blood sugar
• High blood pressure
• Clinical obesity

How Is Cushing's Syndrome Diagnosed?

Because Cushing’s syndrome has many possible causes, diagnosing it can be complex. Your healthcare provider may refer you to an endocrinologist—a doctor specializing in hormonal disorders—for follow-up testing. 

There are several lab tests for Cushing’s syndrome that may require samples of your blood, urine, or saliva for cortisol levels. These tests include:

• Adrenocorticotropic hormone (ACTH) test, which measures the level of ACTH in the blood. This hormone prompts the adrenal glands to produce more cortisol
• Dexamethasone suppression test, which involves taking a low dose of a glucocorticoid and testing your blood cortisol levels 
• Dexamethasone-CRH test, which uses blood samples to differentiate between Cushing’s syndrome and another condition that could be raising cortisol levels

If your healthcare provider believes that your symptoms may be related to a tumor, you may have to undergo imaging tests, such as magnetic resonance imaging (MRI) or a computerized tomography (CT) scan. 

Treatments for Cushing's Syndrome

If you have Cushing’s syndrome, your treatment will depend on the cause of your excess cortisol levels. If corticosteroid exposure is causing your symptoms, your healthcare provider may lower your dose gradually or recommend an alternative medication. 

Meanwhile, Cushing’s syndrome due to a pituitary, adrenal, or other tumor may be treated by:

• Surgery to remove the tumor, the adrenal glands, or both
• Radiation therapy
• Chemotherapy
• Medications to correct hormonal imbalances
• Medications to block cortisol production

How to Prevent Cushing's Syndrome

There’s no way to prevent Cushing’s syndrome caused by tumors or an inherited condition. 

If you are taking or about to start taking any kind of corticosteroid, talk to your healthcare provider about your risk for developing Cushing’s syndrome. They may recommend lowering your dosage, switching to another medication, or taking steroid medicines only as needed.

Related Conditions

Over time, prolonged exposure to very high cortisol levels can increase your risk for various health complications. Many people with Cushing’s syndrome develop comorbid conditions, such as:

• Insulin resistance
• Impaired glucose tolerance
• Diabetes
• Osteoporosis (bone loss)
• Hypertension (high blood pressure)
• High cholesterol
• Depression
• Problems with memory

Cushing’s syndrome can also affect your body’s ability to fight off infections. Plus, muscle weakness and loss of bone density from Cushing's syndrome and its related conditions may make you more prone to falls and fractures.

Living With Cushing's Syndrome

Research suggests that people with Cushing’s syndrome have a heightened risk of death from related health problems such as heart complications and infections. 

If left untreated, Cushing’s syndrome can lead to potentially fatal conditions, including:

• Heart disease
• Heart attack
• Blood clots
• Stroke
• Problems with the kidneys

However, Cushing’s syndrome is usually curable. Diagnosing and treating the disorder early on can help reduce your risk for developing related conditions that might have more lasting symptoms. Talk to your healthcare provider about options for treatment and ways to manage your cortisol levels.