Diagnosis
As noted in the Definition, Classification and Diagnosis of Diabetes, Prediabetes and Metabolic Syndrome chapter (p. S8), glycated hemoglobin (A1C) can be used as 1 of the diagnostic tests for type 2 diabetes in adults. Unfortunately, normal aging is associated with a progressive increase in A1C, and there is a significant discordance between fasting plasma glucose–based and A1C-based diagnosis of diabetes in this age group, a difference that is accentuated by race and gender (2). Pending further studies to define the role of A1C in the diagnosis of diabetes in the elderly, other screening tests may need to be considered in some patients. Screening for diabetes may be warranted in select individuals. In the absence of positive intervention studies on morbidity or mortality in this population, the decision about screening for diabetes should be made on an individual basis.