Cortisol is a hormone that helps the body remain alert and respond to stress by influencing reactions in many different organs and systems in the body. High cortisol levels caused by prolonged stress create a range of health issues, from increased blood pressure to weight gain and premature ageing. But what happens when cortisol levels are too low?
Role of Cortisol and the Adrenal Glands
The adrenal glands (located just above the kidneys) produce several important hormones--epinephrine, norepinephrine, gonadocorticoids (oestrogen and androgen) and a group of hormones called glucocorticoids. Cortisol is one of the glucocorticoids. Cortisol helps maintain blood pressure and cardiovascular function. It slows the inflammatory response and is an important element necessary for balanced metabolism. Its primary role is to help the body maintain the appropriate level of energy to deal with emotional or physical stress.
Effects of Low Cortisol Levels
An insufficient amount of cortisol disrupts metabolism, resulting in low blood sugar and a lack of glycogen, which is stored in the liver and can be rapidly converted into the glucose required for energy. Lack of cortisol also causes a drop in blood pressure, which decreases cardiac output. A discolouration of the skin called hyperpigmentation can occur as a decrease in cortisol stimulates an increase in other hormones that activate the melanocyte cells responsible for skin pigmentation. The overall effect of low cortisol is weakness, dehydration and diminished ability to fight infection, trauma and stress. These issues are often first noticed during periods of extreme stress or trauma. Additionally, infection, surgery or loss of sodium due to excessive sweating can elevate the imbalances to the level of an adrenal crisis.
Symptoms Associated with Low Cortisol
Early symptoms are generic and can be easily confused with other disorders, specifically, fatigue, headache, weakness, dizziness and orthostatic hypotension (low blood pressure upon standing). Nausea, vomiting, and diarrhoea are often present as well as an inability to tolerate cold temperatures. Left untreated, the symptoms progress into muscle weakness, weight loss, dehydration, hypotension, irritability and depression. Ultimately, pain in the abdomen, back or legs, collapse of the peripheral blood vessels and extreme weakness would all indicate adrenal crisis.
Causes of Low Cortisol
Primary causes include atrophy of the adrenal glands as a result of a tumour, inflammation that causes cells to die or an autoimmune response. Some medications can block the synthesis of cortisol. There are also diseases that impact the adrenal gland’s ability to produce enough cortisol, such as polyendocrine deficiency syndrome and a rare endocrine disorder called Addison’s Disease.
Blood tests must be performed to verify levels of cortisol and other hormones that stimulate the release of cortisol. Treatment consists of medication to replace the cortisol (hydrocortisone or prednisone) and to correct imbalances of other elements such as sodium and potassium, which are influenced by the level of cortisol in the blood. Additionally, the physician will screen for any other conditions or diseases that may impact cortisol production. If found, these would have to be treated.