Prediabetes: A high-risk state for developing diabetes
Prediabetes, typically defined as blood glucose levels above normal but below diabetes thresholds, is a risk state that defines a high chance of developing diabetes. Diagnostic criteria for prediabetes have changed over time and currently vary depending on the institution (table 1).
According to the World Health Organization (WHO), high risk for developing diabetes relates to two distinct states, impaired fasting glucose (IFG) defined as fasting plasma glucose (FPG) of 6.1–6.9 mmol/L (in the absence of impaired glucose tolerance – IGT) and IGT defined as postload plasma glucose of 7.8–11.0 mmol/L based on 2-h oral glucose tolerance test (OGTT) or a combination of both.1 The American Diabetes Association (ADA), although applying the same thresholds for IGT, uses a lower cut-off value for IFG (FPG 5.6–6.9 mmol/L) and has additionally introduced haemoglobin A1c levels of 5.7–6.4% as a new category of high diabetes risk.2
The term prediabetes itself has been critised on the basis that (1) many people with prediabetes do not progress to diabetes, (2) the term may imply that no intervention is necessary as no disease is present, and (3) diabetes risk does not necessarily differ between people with prediabetes and those with a combination of other diabetes risk factors. Indeed, the WHO used the term ‘Intermediate Hyperglycaemia’ and an International Expert Committee convened by the ADA the ‘High Risk State of Developing Diabetes’ rather than ‘prediabetes’.1,3 For brevity, we use the term prediabetes in this seminar to refer to IFG, IGT and Continue reading