Stages of type 1 diabetes mellitus

Genetic predisposing factors are present from birth, environmental factors can trigger the disease process, immune biomarkers occur years to decades prior to overt disease, and metabolic abnormalities of deficient insulin secretion begin to appear soon after the onset of beta-cell dysfunction. Individuals with multiple islet autoantibodies and normal glucose tolerance during formal oral glucose tolerance testing (OGTT) are considered to be at stage 1, and those with abnormal glucose tolerance are at stage 2 type 1 diabetes.