Idiopathic type 1 diabetes mellitus is most likely to occur in which populations?

• A. Individuals of African or Asian ancestry.
• B. Individuals of European ancestry.
• C. Only in children under five.
• D. Only in athletes.

Answer: (A)

Idiopathic type 1 diabetes mellitus refers to the form of type 1 diabetes that lacks islet autoantibodies. This non-autoimmune variant tends to occur more often in people of African or Asian ancestry, whereas the autoimmune form is more common among people of European ancestry. So, among populations, individuals of African or Asian descent are the group most likely to have the idiopathic (non-autoimmune) type 1 presentation.

Note that type 1 diabetes can occur at many ages and in various groups, and it is not limited to children under five or to athletes. The key distinction here is the absence of autoantibodies in the idiopathic form, which helps explain the population pattern.