Cortisol is a hormone produced by the adrenal glands usually in response to stress. Cortisol has a range of roles in the body. It helps break down protein, glucose, and lipids. It helps to maintain blood pressure, and, of interest in Lupus, it helps to regulate the immune system.
Heat, cold, infection, trauma, stress, exercise, obesity, and debilitating disease (like Lupus) can influence cortisol concentrations. The hormone is secreted in a daily pattern, rising in the early morning, peaking around 8 am, and declining in the evening. This pattern, which is sometimes called the "diurnal variation" or "circadian rhythm," changes if you work irregular shifts (such as the night shift) and sleep at different times of the day.
Too little amounts of cortisol can cause nonspecific symptoms, such as weight loss, muscle weakness, fatigue, low blood pressure, and abdominal pain. Sometimes decreased production of cortisol combined with a stressor can cause an adrenal crisis that requires immediate medical attention.
Too much cortisol can cause increased blood pressure, high blood sugar, obesity, fragile skin, purple streaks on the abdomen, muscle weakness, and osteoporosis. Women may have irregular menstrual periods and increased facial hair; children may have delayed development and a short stature.
In normal people, cortisol levels are very low at bedtime and at their highest just after waking. Normal values for a blood sample taken at 8 in the morning are 6 - 23 micrograms per deciliter (mcg/dL).
Normal value ranges may vary slightly among different laboratories.
Your test was taken between 7-9 am and the values were normal. Abnormal values could mean:
1) Higher than normal levels may indicate: Adrenal tumor, Cushing's syndrome, Ectopic ACTH-producing tumors
2) Lower than normal levels may indicate: Addison's disease, Hypopituitarism, active Lupus ( Activation of certain autoimmune conditions such as rheumatoid arthritis, Sjogren's syndrome or lupus often occurs with low cortisol levels).
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