Postprandial and basal glucose in type 2 diabetes: assessment and respective impacts.

The independent contribution of postprandial glucose (PPG) excursions to the overall glucose exposure and its role in the development of both micro- and macrovascular complications of diabetes remain subject to continuing debate in type 2 diabetes. Discussion continues on whether postprandial hyperglycemia is the main contributor to the overall hyperglycemia in fairly well-controlled individuals, whereas basal hyperglycemia becomes the preponderant contributor in poorly controlled patients. The concern about the role of PPG as a risk factor for diabetes complications is related to the controversial data obtained in individuals with impaired glucose tolerance. It remains, however, that the total glucose exposure as reflected by hemoglobin A1c (HbA1c) levels is an undoubted major vascular risk factor. Excluding the contribution of PPG is nonsensical. In support of this position is the fact that the absolute impact of PPG on HbA1c, expressed as percentage levels of HbA1c, remains constant at 1% across the HbA1c continuum in non-insulin-treated type 2 diabetes patients. This key feature clearly depicts the absolute contribution of PPG in contrast to its relative contribution and better explains why PPG contributes to the excess of glycation with the basal hyperglycemia.