Addison's is a relatively rare condition, with a worldwide prevalence of 35 to 60 cases per million people.
It is more common in females than males.
It can present insidiously with generalised fatigue and abdominal pain, or acutely in an "Addisonian crisis".
Approximately 90% of the cortex needs to be destroyed to produce insufficiency.
It is commonly associated with other autoimmune (AI) diseases such as thyroid disease and type 1 diabetes.