What is a cortisol test?
Cortisol is a hormone that affects almost every organ and tissue in your body. It plays an important role in helping you to:
Respond to stress
Regulate blood sugar
Maintain blood pressure
Regulate metabolism, the process of how your body uses food and energy
Cortisol is made by your adrenal glands, two small glands located above the kidneys. Most cells within the body have cortisol receptors. Secretion of the hormone is controlled by the hypothalamus, the pituitary gland, and the adrenal gland, a combination of glands often referred to as the HPA axis.
Cortisol is often called the "stress hormone" because of its connection to the stress response, however, cortisol is much more than just a hormone released during stress. Understanding cortisol and its effect on the body will help you balance your hormones and achieve good health.
A cortisol test measures the level of cortisol in your blood, urine, or saliva. Blood tests are the most common way of measuring cortisol. If your cortisol levels are too high or too low, it may mean you have a disorder of your adrenal glands. These disorders can be serious if not treated.
What does cortisol do?
Most bodily cells have cortisol receptors, it affects many different functions in the body. Cortisol can help control blood sugar levels, regulate metabolism, help reduce inflammation, and assist with memory formulation. It has a controlling effect on salt and water balance and helps control blood pressure. In women, cortisol also supports the developing fetus during pregnancy. All these functions make cortisol a crucial hormone to protect overall health and well-being.
Problems associated with high or low cortisol levels
Sometimes tumors on the pituitary or adrenal glands can contribute to a condition known as Cushing syndrome, which is characterized by high levels of cortisol in the blood. Individuals with Cushing syndrome will experience rapid weight gain in the face, abdomen, and chest. Often doctors will notice this because of the individual's slender arms and legs compared to the heavy weight in the core of the body. Cushing syndrome also causes a flushed face, high blood pressure, and changes in the skin. Osteoporosis and mood swings are also a factor considered with Cushing disease.
High cortisol levels can also contribute to changes in a woman's libido and menstrual cycle, even without the presence of Cushing disease. Anxiety and depression may also be linked to high cortisol levels.
Low cortisol levels can cause a condition known as primary adrenal insufficiency or Addison disease. While rare, primary adrenal insufficiency is an autoimmune disease that causes damage to the adrenal glands. Symptoms may start slowly, but they can be quite serious. Patients with primary adrenal insufficiency can experience fatigue, muscle loss, weight loss, mood swings, and changes to the skin.
What is a cortisol test used for?
A cortisol test is used to help diagnose disorders of the adrenal gland. These include Cushing's syndrome, a condition that causes your body to make too much cortisol, and Addison disease, a condition in which your body doesn't make enough cortisol.
Why do I need a cortisol test?
You may need a cortisol test if you have symptoms of Cushing's syndrome or Addison disease.
Symptoms of Cushing's syndrome include:
Obesity, especially in the torso
High blood pressure
High blood sugar
Purple streaks on the stomach
Skin that bruises easily
Women may have irregular menstrual periods and excess hair on the face
Symptoms of Addison disease include:
Dark patches of skin
Low blood pressure
Nausea and vomiting
Decreased body hair
You may also need a cortisol test if you have symptoms of an adrenal crisis, a life-threatening condition that can happen when your cortisol levels are extremely low. Symptoms of an adrenal crisis include:
Very low blood pressure
Sudden and severe pain in the abdomen, lower back, and legs
Loss of consciousness
What do the results mean?
High levels of cortisol may mean you have Cushing's syndrome, while low levels may mean you have Addison disease or another type of adrenal disease. If your cortisol results are not normal, it doesn't necessarily mean you have a medical condition needing treatment. Other factors, including infection, stress, and pregnancy can affect your results. Birth control pills and other medicines can also affect your cortisol levels.
If your cortisol levels are not normal, we will likely order more tests before making a diagnosis. These tests may include additional blood and urine tests and imaging tests, such as CT (computerized tomography) and MRI (magnetic resonance imaging) scans, which allow your provider to look at your adrenal and pituitary glands.