Impaired glucose tolerance as a disease

Current criteria for diagnosing diabetes, based on fasting plasma glucose levels during administration of the oral glucose tolerance test (OGTT), are poorly sensitive and are only modestly predictive of microvascular risk. The period after administration of OGTT is far more predictive and more closely resembles the postprandial state where microvascular risk is elevated. However, persons who do not yet exhibit symptoms of diabetes may nonetheless have impaired glucose tolerance or dysglycemia, whereby macrovascular disease can develop at a glucose level lower than the threshold for microvascular disease and can progress in a graded fashion. This article reviews the factors that may cause dysglycemia (including insulin resistance and obesity) and how diet, blood pressure control, and the use of statins or glycemic/insulin sensitizing may reduce cardiovascular risk in this prediabetic population.