INTRODUCTION
Pre-diabetes is a term used to describe the state where blood glucose levels are above normal but below the threshold for diagnosis of diabetes. An estimated 1 in 3 of the adult population of the UK fall into this group.1 The addition of a coded entry for pre-diabetes to aid adherence to National Institute for Health and Care Excellence (NICE) guidance on follow-up of ‘at risk’ groups is embedding this label within increasing numbers of patients’ lifelong medical records. This article discusses the meaning and significance of this new ‘diagnosis’ at individual and societal level, the controversy that surrounds it, and implications for policy, practice, and research.
IDENTIFICATION OF PRE-DIABETES
In the UK pre-diabetes is usually diagnosed on the basis of an HbA1c level of 42–47 mmol/mol.2 The term is also used to encompass patients identified as being at high risk of diabetes by other testing strategies such as fasting glucose or the oral glucose tolerance test (OGTT). The groups identified as abnormal by different testing strategies do not entirely overlap and there is ongoing debate about which diagnostic test is most appropriate and what the cut-offs should be.3 Despite the limitations of HbA1c in certain groups and its poor sensitivity and specificity if the OGTT is taken as the gold standard,4 its ease of use makes it the most commonly used diagnostic test.
It is estimated that 5–10% of pre-diabetic patients will become diabetic each year with a similar percentage reverting …