Implications of using HBA1C as a diagnostic marker for diabetes.

Diagnosing diabetes now includes a new criterion; hemoglobin A1C ≥6.5 % which can have significant implications. This review compares the advantages and disadvantages of using HbA1C as the main diabetic diagnostic test. HbA1C has greater stability and less variability than plasma glucose measurements but may not always reflect glycemic levels of glycaemia. The present cut off value identifies fewer diabetics than glucose-based criteria. HbA1C being more convenient could diagnose more patients but this is not yet proven. When choosing a diagnostic test, the limitations of each test must be clearly understood to use appropriate clinical judgment and consider patient preference.