Adrenal Insufficiency, Adrenal Fatigue and Cushing’s – Do you know the difference?

The terms Adrenal Insufficiency (AI), Adrenal fatigue and Cushing’s Syndrome relate to the Endocrine system.

The endocrine system is made up of glands that produce hormones. These hormones work together to regulate the systems of your body such as, blood pressure, temperature, and metabolism.

The adrenal glands sit on top of the kidneys. One of the hormones they produce is cortisol. Cortisol is essential to life, is essential to maintain many basic body functions, such as blood pressure and heart rate. Lack of cortisol can result in heart failure or coma in as little as 30 minutes. It’s often called the “stress hormone” because it is responsible for the fight or flight response to stress and danger.

Adrenal insufficiency (AI)

Adrenal insufficiency (click here for detailed information) occurs when the adrenal glands are unable to produce enough cortisol to maintain the balance (homeostasis) of blood pressure, electrolytes, and metabolic energy.

AI is life-threatening because, as mentioned above, cortisol is essential to maintain many basic body functions. Most adrenal insufficient patients are dependent on cortisol replacement for life. The non-specific symptoms of AI, such as nausea, fatigue, and pain are often mistaken for other conditions. There are over sixty causes of AI, including genetic mutations, autoimmune disease, infections, head injury, and steroid treatment for other conditions such as asthma and cancer. AI is classified as Primary, Secondary, or Tertiary depending on where it originates.

• Primary adrenal insufficiency (PAI) originates in the adrenal glands. Examples of PAI include adrenal tumor, infections, and autoimmune disease. PAI is usually accompanied by an aldosterone deficiency and requires mineral steroid replacement also.
  
• Secondary adrenal insufficiency (SAI) originates in the pituitary gland. Some examples of SAI are head injury, Sheehan’s syndrome (excessive blood loss during childbirth) and empty sella. SAI is also known as hypopituitarism. Because the pituitary sends signals to both the adrenal and thyroid glands, SAI is often complicated by multiple hormone deficiencies.
  
• Tertiary adrenal insufficiency (TAI) originates in the hypothalamus. Examples include hypothalamic tumors, suppression from steroids used to treat other conditions, and treatment for Cushing’s Syndrome.

Cushing’s Syndrome

Cushing’s Syndrome is a condition where the body has too much cortisol. It can be caused by taking replacement cortisol in excess of what your body can use, or from your body producing too much cortisol. Adrenal, pituitary, or ectopic tumors can cause the body to produce too much cortisol. When a pituitary tumor causes overproduction of adrenocorticotropic hormone, ACTH, it’s called Cushing’s Disease. ACTH signals the adrenal glands to produce cortisol. Surgery to correct Cushing’s Syndrome can cause adrenal insufficiency.

Adrenal fatigue (AF)

The term, adrenal fatigue (AF) is based on the theory that under constant stress the adrenal glands can wear out, and will eventually not produce enough cortisol, causing extreme fatigue. Currently, there are no tests recognised by the medical community that can support this theory. Therefore people who experience symptoms of extreme fatigue and suspected AF should get tested for adrenal insufficiency and/or Cushing’s syndrome.  

Parameters for the diagnosis of AF have not been established.
Without defined test results, a diagnosis of adrenal fatigue is often based on symptoms.

A person diagnosed with adrenal fatigue may actually have a life-threatening endocrine disorder, such as adrenal insufficiency (not enough cortisol) or Cushing’s syndrome (too much cortisol).
We recommend testing for adrenal insufficiency if symptoms are severe enough to interfere with daily function.