The contribution of postmeal plasma glucose to HbA 1c is proportionally greatest with HbA 1c values of 6.5%, while nocturnal FPG is at a near-normal level. As HbA 1c rises above 8%, the relative contribution of postmeal hyperglycaemia to overall glycaemic control diminishes, while the contribution of FPG predominates.
These results explain previous findings that, while the contribution of postmeal plasma glucose to overall glycaemia is ~70% at HbA 1c values < 7.3%, the postmeal contribution is ~40% with HbA 1c values above 9.3%.
Such findings form the basis for a glucose triad model of diabetes management, in which all three glycaemic parameters of HbA 1c, PMG and FPG interrelate, and are essential targets for intervention in attempts to optimize overall glycaemic control (Fig.).
A Ceriello and S Colagiuri et al. Diabet Med. 2008 October; 25(10): 1151–1156. |