Control of post-prandial hyperglycemia--an essential part of good diabetes treatment and prevention of cardiovascular complications.

Aim: This article reviews the relationship between the control of post-prandial hyperglycemia and diabetes-related complications.

Data Synthesis: Hyperglycemia is a modifiable risk factor that has a deleterious effect on the development and progression of microvascular and macrovascular complications in patients with type 2 diabetes. The UK Prospective Diabetes Study revealed how reductions in hemoglobin A1c (HbA1c) correlate with a significant reduction in all-cause mortality and the incidence of myocardial infarction. The Diabetes Intervention Study showed that poor control of fasting glycemia does not increase the risk of myocardial infarction or mortality, whereas poor control of post-prandial glucose is associated with a high all-cause mortality rate. HbA1c is the standard measure for metabolic control and therapeutic efficacy, but does not reflect fluctuations in glycemic control. Plasma glucose concentrations in healthy subjects remain within a narrow range, which suggests that the fluctuations in glucose levels caused by inappropriate treatment may have negative consequences. These fluctuations have been associated with acute adverse effects (particularly excessive post-prandial hyperglycemia, pre-meal hypoglycemia and weight gain) that counteract the positive effect of lowering fasting plasma glucose and HbA1c. Post-prandial hyperglycemia and spikes also have deleterious effects on insulin secretion and sensitivity. Prandial oral antidiabetic agents such as alpha-glucosidase inhibitors (acarbose, miglitol) and rapidly acting insulin secretagogues (nateglinide, repaglinide) have recently been introduced to improve the control of post-prandial hyperglycemia.

Conclusion: Near-normal post-prandial glycemic control is associated with lower rates of cardiovascular and all-cause mortality than excessive post-challenge hyperglycemia. In addition to the aggressive control of HbA1c and fasting plasma glucose, the strict normalisation of postprandial hyperglycemia is an essential part of good diabetes treatment. There is growing evidence from epidemiological and clinical studies that this also reduces the risk of cardiovascular complications.