Cortisol PM
Test Overview
The Cortisol PM Test measures the level of cortisol in the blood in the afternoon or evening. Cortisol is a hormone produced by the adrenal glands that plays a key role in the body’s response to stress, metabolism, immune function, and sleep-wake cycles. Cortisol levels typically fluctuate throughout the day, with higher levels in the morning and lower levels in the evening. A PM cortisol test helps assess how well the body’s cortisol cycle is functioning, and may be used to diagnose conditions such as adrenal insufficiency, Cushing’s syndrome, and Addison’s disease.
Test Uses
- Assess adrenal function (to detect disorders like Cushing’s syndrome or Addison’s disease).
- Evaluate symptoms of abnormal cortisol levels (e.g., fatigue, weight changes, mood swings).
- Monitor patients undergoing treatment for adrenal disorders.
- Help diagnose adrenal insufficiency or hyperfunction.
Cortisol PM Test Results & Ranges
| Test Component: | Normal Range: | Abnormal Levels Indicate: |
|---|---|---|
| Cortisol (PM) | 3 – 10 mcg/dL (varies slightly depending on lab reference) | High: Cushing’s syndrome, stress, depression, obesity, certain medications (e.g., steroids) Low: Addison’s disease, adrenal insufficiency, pituitary dysfunction, prolonged illness, malnutrition |
Interpreting Abnormal Cortisol Levels:
-
High Cortisol Levels (PM):
- Cushing’s syndrome: A condition where the body produces too much cortisol, often caused by pituitary or adrenal tumors.
- Chronic stress: Long-term emotional or physical stress can elevate cortisol levels.
- Medications: Certain drugs (e.g., corticosteroids) can artificially raise cortisol levels.
- Obesity or depression: Both can lead to higher cortisol levels.
-
Low Cortisol Levels (PM):
- Addison’s disease: A disorder where the adrenal glands produce insufficient cortisol.
- Adrenal insufficiency: Caused by problems with the adrenal glands or pituitary gland.
- Pituitary dysfunction: Impaired secretion of ACTH, which signals the adrenal glands to release cortisol.
- Chronic illness or malnutrition: Long-term health problems can suppress cortisol production.
Expected Turnaround Time
- Results Available: Typically within 1-2 days.
Specimen Requirements
- Sample Type: Blood (serum).
- Container: Serum separator tube (SST, gold-top tube).
Collection Instructions
- Timing: This test must be done in the afternoon or evening to assess cortisol levels during the period of natural decline.
- Fasting is not required, but avoid heavy exercise or stress prior to the test.
- Medications: Inform the doctor about any medications (e.g., steroids) that could affect cortisol levels.
Test Details
Clinical Use: Helps diagnose conditions like Addison’s disease, Cushing’s syndrome, and adrenal insufficiency. Monitors the body’s cortisol rhythm, which is crucial for healthy metabolic and immune responses. Can be used to assess treatment effectiveness in adrenal disorders.
Limitations: Cortisol levels fluctuate naturally during the day, so the timing of the sample collection is crucial for accurate results. Results may be influenced by medications, stress, and the body’s natural circadian rhythm.
The Cortisol PM Test is important for assessing adrenal function and diagnosing conditions related to abnormal cortisol production, ensuring appropriate treatment for adrenal disorders.