In individuals with Addison's disease, what is often seen in their plasma cortisol levels?

In individuals with Addison's disease, decreased levels of plasma cortisol are a hallmark feature of the condition. This disorder is characterized by the adrenal glands' inability to produce sufficient amounts of cortisol due to damage or dysfunction, often stemming from autoimmune processes, infections, or other underlying health issues.

Cortisol is a critical hormone involved in regulating various bodily functions, including metabolism, immune response, and stress response. When the adrenal glands are insufficiently secreting cortisol, it leads to a state of adrenal insufficiency, which manifests in both laboratory findings of low plasma cortisol levels and clinical symptoms such as fatigue, weight loss, low blood pressure, and hyperpigmentation of the skin.

In Addison's disease, the lack of cortisol can be confirmed through adrenal function testing, particularly the ACTH stimulation test, which typically yields low cortisol levels despite elevated adrenocorticotropic hormone (ACTH). Understanding this physiological basis is essential for recognizing Addison's disease and its implications on patient health.