Look for signs of insulin deficiency rather than insulin resistance alone. Examples include unintentional weight loss, rapid symptom onset, ketosis or DKA at presentation, or poor response to typical type 2 regimens. On exams, the strongest confirmatory tools are positive diabetes autoantibodies (often GAD65) and low or inappropriately normal C-peptide for the degree of hyperglycemia.

Yes. Type 2 diabetes can progress as beta cell function declines, and insulin may be added for persistent hyperglycemia, during acute illness, or around surgery. Insulin use does not redefine the type. The diagnosis depends on underlying pathophysiology and supporting tests, not on the medication list.

DKA is more common in type 1 because near-absolute insulin deficiency promotes ketone production. It can still occur in type 2, especially with severe physiologic stress, missed insulin in insulin-requiring type 2, or ketosis-prone diabetes. Quiz items often reward recognizing that type 2 is more classically associated with hyperosmolar hyperglycemic state (HHS), while DKA is the “classic” emergency for type 1.

A1C supports the diagnosis of diabetes and estimates average glycemia over the prior 2 to 3 months, but it does not identify the diabetes type by itself. It also can miss high variability, such as frequent hypoglycemia balanced by hyperglycemia. If an answer choice involves post-meal spikes, nocturnal lows, or time-in-range, think SMBG or CGM concepts instead of A1C alone.

Stress hormones can raise glucose and increase insulin needs, and depression is associated with worse self-management and higher complication risk. If a question mixes mood symptoms with adherence problems or recurrent highs, address both medical and behavioral factors. For related review, see Check Your Mental Health Awareness Knowledge and Test Your First Aid and CPR Skills.