ÎPrediabetes can be identified by the presence of impaired glucose tolerance, which is an OGTT glucose value of 140 to 199 mg/dL 2 hours after ingesting 75 g of glucose and/or impaired fasting glucose, which is a fasting glucose value of 100 to 125 mg/dL (Table 1) (D-4).
> HbA1c values between 5.5% and 6.4% should be a signal to do more specific glucose testing (D-4).
> HbA1c testing should be used as a screening tool only; FPG measurement or an OGTT should be used for definitive diagnosis (D-4).
ÎThere is a continuum of risk for poor patient outcomes in the progression from normal glucose tolerance to overt T2DM (D-4).
ÎThe following criteria may be used to diagnose DM (Table 1) (A-1):
> FPG concentration (after 8 or more hours of no caloric intake) ≥ 126 mg/dL OR > Plasma glucose concentration of ≥ 200 mg/dL 2 hours after ingesting 75-g oral glucose load in the morning after an overnight fast of at least 8 hours OR
> Symptoms of uncontrolled hyperglycemia (eg, polyuria, polydipsia, polyphagia) and a random (casual, nonfasting) plasma glucose concentration ≥ 200 mg/dL OR > HbA1c level of 6.5% or higher.
ÎIn pregnancy, elevated plasma glucose levels (FPG concentration > 92 mg/dL; 1-hour postchallenge glucose value ≥ 180 mg/dL; or 2-hour value ≥ 153 mg/dL) satisfy the criteria for a diagnosis of GDM (C-3).
> All pregnant women should be screened for GDM at 24 to 28 weeks' gestation using a 75-g (glucose), 2-hour OGTT.
Related Conditions Asymptomatic Coronary Artery Disease
ÎMeasurement of coronary artery calcification or coronary imaging may be used to assess whether a patient is a reasonable candidate for intensification of glycemic, lipid, and/or blood pressure control (C-3).
ÎScreening for asymptomatic coronary artery disease with various stress tests in patients with T2DM has not been clearly demonstrated to improve cardiac outcomes and is therefore NOT recommended (D-4).
Sleep-Related Problems
ÎObstructive sleep apnea is common and should be screened for in adults with T2DM, especially in men older than 50 years (D-4).
ÎContinuous positive airway pressure should be considered for treating patients with obstructive sleep apnea (A-1).
Note: This condition can be diagnosed by history or by home monitoring, but referral to a sleep specialist should be considered in patients suspected of having obstructive sleep apnea or restless leg syndrome (D-4).
3
> Metabolic syndrome based on National Cholesterol Education Program IV Adult Treatment Panel III criteria is a prediabetes equivalent (C-3).
