Table 1

Diagnosis of pre-diabetes

Type of pre-diabetesDescriptionDiagnostic test usedCriteria for diagnosisIncidence of T2DM
(per person-year)12
WHO8ADA9IEC10
Impaired glucose toleranceHigh blood glucose 2 hours after a drink containing 75 g of sugar (eg, Lucozade)Oral glucose tolerance test2 hours postload glucose of 7–11.1 mmol/L2 hours postload glucose of 7–11.1 mmol/LN/A0.045
Impaired fasting glucoseHigh blood glucose following a period of fastingFasting plasma glucose6.0–6.9 mmol/L5.6–6.9 mmol/LN/AWHO criteria: 0.047
ADA criteria: 0.036
HbA1c ‘at risk’ rangeGlycated haemoglobin which estimates blood glucose levels over the previous 2–3 monthsHbA1c6.0%–6.4%5.7%–6.4%6.0%–6.4%WHO criteria: 0.036
Impaired glucose tolerance and impaired fasting glucoseAs aboveFasting plasma glucose and oral glucose tolerance test2 hours postload glucose: 7–11.1 mmol/L and
fasting plasma glucose: 6.0–6.9 mmol/L		2 hours postload glucose: 7–11.1 mmol/L and
fasting plasma glucose: 5.6–6.9 mmol/L		N/A0.070

  • ADA, American Diabetes Association; IEC, International Expert Committee; N/A, Not applicable; T2DM, Type 2 Diabetes Mellitus.