Diabetes diagnosis criteria:
Oral administration of 100g of glucose, blood samples are taken to measure venous plasma glucose concentrations before and 0, 0.5, 1, 2, and 3 hours after sugar administration. The highest limit values for determination are 6.9mmol/L, 11.1mmol/L, 10.5mmol/L, 8.3mmol/L, and 6.9mmol/L, respectively. For patients aged 50 and over, the values at 0.5, 1, and 2 hours increase by 0.28mmol/L, 0.56mmol/L, and 0.28mmol/L for each 10-year increment in age.
Combining the 0.5-hour and 1-hour values into 1 point, there are a total of 4 points. If 3 of the 4 points are higher than the standard limits, diabetes is diagnosed. If there are 2 points that are abnormal or the blood glucose level in the oral glucose tolerance test (OGTT) exceeds the normal range but does not reach the diabetes diagnosis criteria, it is classified as impaired glucose tolerance. Patients with typical diabetes symptoms or a history of diabetic ketoacidosis, fasting blood glucose levels greater than or equal to 7.2mmol/L twice or more, or postprandial blood glucose levels greater than or equal to 11.1mmol/L, can be directly diagnosed with diabetes.
1985 WHO Diagnostic Criteria: With the increase in international academic exchanges, the revised diabetes diagnosis criteria from the WHO in 1985 are widely used. The method for measuring blood glucose is venous plasma true sugar method, and 75g of glucose is used for the OGTT.
- Diabetes diagnosis criteria with symptoms: Any of the following three conditions can be diagnosed as diabetes: ① Blood glucose ≥ 11.1mmol/L at any time during the day, ② Fasting blood glucose ≥ 7.8mmol/L, ③ Fasting blood glucose < 7.8mmol/L but blood glucose ≥ 11.1mmol/L in the OGTT at 2 hours.
- Diabetes diagnosis criteria without symptoms: One of the following two conditions can also be diagnosed as diabetes: ① Two consecutive fasting blood glucose levels ≥ 7.8mmol/L, ② OneOGTT with blood glucose levels ≥ 11.1mmol/L at 1 hour and 2 hours, or another OGTT with blood glucose ≥ 11.1mmol/L at 2 hours, or repeating fasting blood glucose ≥ 7.8mmol/L.
- Impaired glucose tolerance (IGT) criteria: Fasting blood glucose levels above normal but below 7.8mmol/L, and OGTT blood glucose levels between 7.8 and 11.1mmol/L. These criteria also apply to pregnant women, but women with IGT should be treated as having diabetes.
Latest WHO standards: In December 1996, the WHO Consultative Meeting on Diabetes and Its Complications Diagnostic Criteria and Classification was held in the United Kingdom, and new diabetes diagnostic criteria were proposed. The fasting blood glucose criterion was changed to > 7.0mmol/L.
