This report recommends that the diagnosis of diabetes is made if the HBA1c level is 6.5% or above. Diagnosis should be confirmed with a repeat HBa1c test unless clinical symptoms and glucose levels of above 11.1mmoles/l are present. If HBA1c testing is not possible owing to patient factors that preclude its interpretation (e.g. haemaglobinopathy) previously recommended diagnostic glucose levels should be used. The diagnosis of diabetes during pregnancy, when changes in red cell turnover make the HBA1c assay problematical will continue to require glucose measurements.
The report states that individuals with a HBA1c at or above 6% but below 6.5% are likely at the highest risk for progression to diabetes, but this range should not be considered an absolute threshold at which preventative measures are initiated.