When is Diabetes?—A New Look at Diagnostic Criteria for Diabetes Mellitus

Summary: While the diagnosis of diabetes mellitus is usually straightforward because of typical symptoms and signs along with an unequivocally high plasma glucose, there is still considerable controversy about diagnostic criteria for diabetes based on the oral glucose tolerance test (OGTT). Recently there has been world‐wide recognition of the need for standardisation of these criteria. A new set of diagnostic criteria, based on prospective and cross‐sectional epidemiologic studies have now been recommended by a World Health Organisation Expert Committee on Diabetes. The new criteria set out recommendations for normal subjects, those with impaired glucose tolerance (a borderline group), and diabetics. The use of these criteria should result in uniform reporting of the OGTT, as well as reducing to a minimum the mis‐diagnosis of diabetes.