Definitions (and Current Controversies) of Diabetes and Prediabetes.
Level 5 - mechanism / opinion, no new human data
Narrative review without systematic search methodology
PubMed 25612821 · doi:10.2174/1573399811666150122150233
What was done
This narrative review summarizes standard diagnostic criteria for type 2 diabetes and prediabetes (primarily based on American Diabetes Association position statements) and highlights ongoing controversies regarding testing methods and diagnostic thresholds.
What was found
The review outlines the following standard diagnostic cutoffs: - Diabetes: Fasting plasma glucose ≥ 126 mg/dl (7.0 mmol/l), casual plasma glucose ≥ 200 mg/dl (11.1 mmol/l) in the presence of symptoms, 2-hour 75-g oral glucose tolerance test (OGTT) ≥ 200 mg/dl (11.1 mmol/l), or HbA1c ≥ 6.5%. - Prediabetes: Impaired fasting glucose (fasting plasma glucose 100–125 mg/dl [5.6–6.9 mmol/l]), impaired glucose tolerance (2-hour OGTT 140–199 mg/dl [7.8–11.0 mmol/l]), or HbA1c 5.7–6.4%. The abstract notes ongoing debates regarding the threshold defining impaired fasting glucose, potential discordance between diagnostic tests, and the adequacy of HbA1c as a standalone tool for prediabetes.
Why it matters
It provides a clear summary of established diagnostic thresholds across glycemic modalities while identifying known areas of diagnostic discrepancy in clinical screening.
Limits
As a narrative review, it presents consensus definitions rather than primary empirical data or a systematic review with meta-analysis. The abstract reports no quantitative diagnostic test accuracy metrics (such as sensitivity, specificity, or predictive values) or sample characteristics.
Cited by
- supports The standard fasting blood glucose cutoff between healthy and prediabetes is 100 mg/dL in non-pregnant adults, whereas in pregnancy a fasting level above 92 mg/dL indicates gestational diabetes.