Lexicon
Glucose
Also known as Blood Glucose
Definition
Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c in the blood. [1] [2] Prediabetes is an intermediate stage between normal glucose regulation and diabetes that affects roughly 1 in 3 adults in the US. [3] A lower cutoff for fasting plasma glucose of 126 mg per dL (7 mmol per L) or higher confirms the diagnosis of diabetes mellitus and provides a more reliable means of identifying persons at risk of complications from hyperglycemia. [4]
How it works
Overt type 2 diabetes is preceded by prediabetes and a latent phase, so glucose can remain in the diagnostic-threshold range for years before overt disease. [5] Fasting plasma glucose has only modest sensitivity for hyperglycemia screening, exhibiting a sensitivity of 56% and specificity of 97.7% at the 126 mg/dL cut-off when validated against the 75-g oral glucose tolerance test. [5] Because a single reading captures only one instant, continuous glucose monitoring addresses limitations of HbA1c and self-monitoring by reflecting intra- and inter-day glycemic excursions that may lead to hypoglycemia or postprandial hyperglycemia. [6]
Connected concepts
How it's measured
Glycemic control is monitored by people with diabetes measuring their own blood glucose with meters and with continuous interstitial glucose monitoring devices, in addition to laboratory analysis of HbA1c. [1] The 75-g oral glucose tolerance test is accepted as the gold-standard diagnostic test for diabetes and prediabetes and distinguishes impaired fasting glucose from impaired glucose tolerance. [5] For continuous glucose monitoring, time in range generally refers to the time spent in an individual's target glucose range, usually 70 to 180 mg/dL. [6]
What levels mean
Prediabetes is defined by a fasting glucose level of 100 to 125 mg/dL or a glucose level of 140 to 199 mg/dL measured 2 hours after a 75-g oral glucose load. [3] Impaired fasting glucose is defined as 100 to 125 mg/dL (5.6 to 6.9 mmol/l) by the ADA.
Community knowledge
## Monitoring And Risk Markers
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- 1.Sacks DB, Arnold M, Bakris GL, Bruns DE, Horvath AR, Lernmark Å, Metzger BE, Nathan DM. Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus. Diabetes Care · 2023
- 2.Sacks DB, Arnold M, Bakris GL, Bruns DE, Horvath AR, Lernmark Å, Metzger BE, Nathan DM. Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus. Clin Chem · 2023
- 3.Echouffo-Tcheugui JB, Perreault L, Ji L, Dagogo-Jack S. Diagnosis and Management of Prediabetes: A Review. JAMA · 2023
- 4.Mayfield J. Diagnosis and classification of diabetes mellitus: new criteria. Am Fam Physician · 1998
- 5.Duan D, Kengne AP, Echouffo-Tcheugui JB. Screening for Diabetes and Prediabetes. Endocrinol Metab Clin North Am · 2021
- 6.Danne T, Nimri R, Battelino T, Bergenstal RM, Close KL, DeVries JH, Garg S, Heinemann L.
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