Update on diabetes diagnosis: a historical review of the dilemma of the diagnostic utility of glycohemoglobin A1c and a proposal for a combined glucose-A1c diagnostic method

The role of glycohemoglobin A1c [A1c] for the diagnosis of diabetes has been debated for over three decades. Recently, the American Diabetes Association [ADA] has recommended adding A1c as an additional criterion for diabetes diagnosis. In view of the continued debate about the diagnostic utility of A1c, and in view of the unabated burden of undiagnosed diabetes, the search for alternative diagnostic methods is discussed. A historical literature review is provided, in view of the new ADA diagnostic guidelines, and a proposal is provided for combining A1c and a glucose measurement as a diagnostic alternative/adjunct to the use of a single criterion. This proposal is based on the non-overlapping of the advantages and disadvantages of these individual tests. The cost-effectiveness of this method remains to be tested

challenge of undiagnosed pre-diabetes, diabetes and associated cardiovascular disease

To present the challenges of undiagnosed pre-diabetes, diabetes and associated cardiovascular disease. A substantial number of people with diabetes and pre-diabetes remain undiagnosed worldwide. Without preventive measures, pre-diabetes progresses to overt diabetes at the rate of approximately 5% per year. Both diabetes and pre-diabetes are associated with vascular complications. Undiagnosed pre-diabetes and diabetes is a major health problem, and we recommend widespread screening for diabetes. An international expert committee has recommended that HbAlc be used for the diagnosis of diabetes. Further studies are needed before HbAlc can be used as a diagnostic test for gestational diabetes

Hemoglobin A1c: past, present and future

Hemoglobin A[HbA] has been used for decades to monitor the control of glycemia in diabetes. Although HbA1c is currently undergoing a reassessment, and major developments have been underway in recent years, HbA1c is not recommended at present for diabetes screening or diagnosis. The objective of this review is to summarize the recent developments and to review a potential diagnostic role for HbA1c. Implementation of changes in HbA1c results and units of measurements have been suggested for the purpose of test standardization. These include lower reference ranges [by about 1.5-2 points] and measurement units expressed in percentage [%], as mg/dL [mmol/L] or mmol/mol [or a combination of these units]. In diabetes screening and diagnosis, the current diagnostic guidelines use measurement of plasma glucose either fasting or after glucose load. These diagnostic methods have shortcomings warranting a potential diagnostic role for HbA1c. While recent developments in HbA1c methodologies are acknowledged, it is not yet known which changes will be implemented, and how soon. Given the recent literature supporting HbA1c diagnostic abilities, and given the shortcomings of the current guidelines, it is possible that a diagnostic role for HbA1c may be considered in future practice guidelines, globally. Very recently, the first of such recommendations has been proposed by an expert panel, as announced by the US Endocrine Society