Diagnosing diabetes—time for a change?

Abstract

Recently an International Expert Committee including the authors of this paper proposed a revision of the diagnostic criteria for diabetes, recommending that HbA1c may be a better means of diagnosing diabetes than measures of glucose (fasting and/or post-challenge) and that it be adopted as a diagnostic criterion for diabetes [1]. The international expert committee acknowledges that practical, medical, methodological and financial factors may prevent implementation of the recommendation, and in these cases recommends that current standard diagnostic methods are retained. The recommendation is based on the association of microvascular complications with HbA1c being at least as strong as those with fasting or post-challenge glucose, that HbA1c is subject to less day-to-day variability than fasting or post-challenge glucose, and can be measured at any time of the day without preparations such as fasting or a glucose challenge. So far, this is a proposal to be considered by organisations such as the EASD, American Diabetes Association (ADA), International Diabetes Federation (IDF) and the WHO, as well as by authorities in individual countries worldwide. This decision is not trivial. Redefining diagnostic criteria may re-define the severity of the disease [2], and if the same criteria are not used in all countries (as has been the case since 1997), a transatlantic trip may cure or cause diabetes simply as a result of small but important differences in diagnostic criteria [3, 4]. Redefining diagnostic criteria usually means that one set of criteria is replaced by another. Having different diagnostic procedures in place at the same time potentially creates confusion, not clarity. Consequently, now is the time for a careful evaluation of the existing evidence and the public health, economic and practical implications of redefining the diagnostic criteria for diabetes.