Integrating glycaemic variability in the glycaemic disorders of type 2 diabetes: a move towards a unified glucose tetrad concept.

The high incidence of atherosclerosis and cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes. Evidence is accumulating that postprandial hyperglycaemia is an independent risk factor for diabetes-associated complications and mortality, and that worsening diabetes control is characterized by postprandial glucose (PPG) deterioration preceding an impairment in fasting glucose levels. Postprandial and general glucose fluctuations play a major role in activating oxidative stress, leading to the endothelial dysfunction, one of the mechanisms responsible for vascular complications. Therefore, the management of PPG is key for any strategy used in the monitoring and treatment of diabetes. We recommend that any strategy aimed at controlling the glycaemic disorders associated with type 2 diabetes, and limiting the risk of complications, should target the 'glucose tetrad', which comprises the following components: HbA(1c), fasting and postprandial plasma glucose, and markers of glycaemic variability, such as the mean amplitude of glycaemic excursions (MAGE) index. This brings together, in a simple, unified concept, the conventional markers (HbA(1c) and fasting glucose) and the more recently recognized markers of glycaemic control (PPG excursions and acute glycaemic variability).