Prediabetes

Prediabetes or intermediate hyperglycaemia represents a preliminary stage in the development of type 2 diabetes mellitus (T2DM). In addition to an increased likelihood of developing T2DM, individuals with prediabetes have an elevated risk of various vascular and non-vascular complications. No consensus has been achieved on the ideal screening strategy for prediabetes, with fasting plasma glucose concentration, glycated haemoglobin (HbA1c) and the oral glucose tolerance test being the most frequently measured parameters. The two major phenotypes of prediabetes, that is, impaired fasting glucose and impaired glucose tolerance, may represent different pathophysiologies with varying natural history, risk of adverse outcomes and responsiveness to treatment. Most of the evidence for managing prediabetes focuses on lifestyle modification with or without medications in individuals with overweight or obesity and impaired glucose tolerance. Whether these interventions are beneficial in individuals with impaired fasting glucose and those of normal body weight is unclear, as is the cost-effectiveness and sustainability of pharmacotherapy for treating prediabetes. Large-scale national T2DM prevention programmes are currently under way to assess whether the benefits of interventions for prediabetes can be translated to the community setting.