Table 1

Reasons to prefer A1C compared with plasma glucose determination for diagnosing diabetes

Chronic hyperglycemia is captured by A1C but not by FPG (even when repeated twice).
Microangiopathic complications (retinopathy) are associated with A1C as strongly as with FPG.
A1C is better related to cardiovascular disease than FPG.
Fasting is not needed for A1C assessment.
No acute perturbations (e.g., stress, diet, exercise, smoking) affect A1C.
A1C has a greater pre-analytical stability than blood glucose.
A1C has an analytical variability not inferior to blood glucose.
Standardization of A1C assay is not inferior to blood glucose assay.
Biological variability of A1C is lower than FPG and 2-h OGTT PG.
Individual susceptibility to protein glycation might be caught by A1C.
A1C can be used concomitantly for diagnosing and initiating diabetes monitoring.
Diabetes assessment with A1C assay is not necessarily greater than with glucose assessment.