Analysis of Early Warning and Clinical Classification of Prediabetes: Identifying Impaired Glucose Regulation and the Latest International Diagnostic Criteria

II. Early Self-Awareness in Sub-healthy Individuals with Diabetes: A medical examination report showing "fasting blood glucose" and "two-hour postprandial blood glucose" higher than normal standards does not necessarily indicate diabetes. This condition is called "impaired glucose regulation" (IGR), the pre-diabetic stage. "Diabetes is a slow-developing process. From normal blood glucose levels to 'impaired glucose regulation,' and then to the stage of diabetes, the average onset process takes 10-15 years. During this period, there is significant potential for proactive prevention and treatment." Currently, the authoritative medical opinion holds that diabetes is a disease requiring lifelong treatment, but in the "impaired glucose regulation" stage, it is possible to restore blood glucose to normal levels through active intervention. Identify the host indicators for each stage of diabetes development. According to the standards issued by the World Health Organization, normal fasting blood glucose should be below 6.1 mmol/L (110 mg/dL), and two-hour postprandial blood glucose should be below 7.8 mmol/L (140 mg/dL). A fasting blood glucose level ≥7.0 mmol/L (126 mg/dL) and a two-hour postprandial blood glucose level ≥11.1 mmol/L (200 mg/dL) meet the diagnostic criteria for diabetes. Between these two levels, fasting blood glucose between 6.1 and 7.0 mmol/L (110–126 mg/dL) or two-hour postprandial blood glucose between 7.8 and 11.0 mmol/L (140–200 mg/dL), is considered "impaired glucose regulation," also known as prediabetes. It is important to note that even if all blood glucose indicators in a medical examination report are within the normal range, fasting blood glucose levels should still be closely monitored. Recent studies in the United States have shown that when fasting blood glucose exceeds 5.6 mmol/L, insulin secretion in the body begins to be affected; therefore, the United States has lowered the standard for normal fasting blood glucose to 5.6 mmol/L. Although China still uses the old standards of the World Health Organization, experts remind citizens that anyone whose fasting blood glucose level exceeds 5.6 mmol/L during a physical examination should still be classified as a "high-risk group" for diabetes and undergo diabetes screening to prevent and treat diabetes as early as possible.

Section 2: Basic Knowledge of Diabetes I. Normal Blood Glucose Values ​​It is crucial to affirm that there is only one standard for diagnosing diabetes: blood glucose. You cannot diagnose diabetes based on urine glucose, because the presence of sugar in urine is only one diagnostic criterion, but the absence of sugar in urine does not necessarily rule out diabetes. The sole diagnostic criterion is blood glucose. Generally, blood glucose testing first checks fasting blood glucose. If diabetes is suspected, blood glucose two hours after a meal is also checked. Simply put, the normal fasting blood glucose level is below 6.1 mmol/L (110 mg/dL). The diagnostic standard for diabetes using fasting blood glucose is above 7.0 mmol/L (126 mg/dL). It can be seen that there is a difference between the normal fasting blood glucose level and the diagnostic standard for diabetes. Some people have fasting blood glucose levels between these two values. While this doesn't necessarily mean their blood glucose is abnormal, it doesn't necessarily indicate diabetes. This phenomenon is now called elevated fasting blood glucose, and individuals in this group are at high risk for diabetes. Furthermore, blood glucose levels two hours after a meal are also very important. The normal postprandial blood glucose level is below 7.8 mmol/L (140 mg/dL). The diagnostic criteria for diabetes are a blood glucose level of 11.1 mmol/L (200 mg/dL) or higher. There is a gap between 7.8 mmol/L (140 mg/dL) and 11.1 mmol/L (200 mg/dL). If blood glucose levels fall within this range, it's now called postprandial hyperglycemia. While this isn't diabetes, it's not normal either; individuals at high risk for diabetes are at risk. Therefore, elevated blood glucose levels in non-diabetic individuals are also dangerous and require careful attention, as it can quickly develop into diabetes if left unchecked. Even if blood glucose levels are temporarily normal, preventative measures against diabetes are necessary if certain risk factors are present.

II. Diagnostic Criteria for Diabetes Mellitus Based on the criteria established by the World Health Organization (WHO) Expert Committee on Diabetes in 1980 and 1985, diabetes mellitus can be diagnosed if any of the following conditions are met: (1) Having symptoms of diabetes mellitus, with fasting blood glucose exceeding 7.8 mmol/L (140 mg/dL) on two or more occasions. (2) Having symptoms of diabetes mellitus, with blood glucose exceeding 11.1 mmol/L (200 mg/dL) at any time. (3) Fasting blood glucose below 7.8 mmol/L, suspected of having diabetes mellitus should undergo a 75g glucose tolerance test. Blood glucose exceeding 11.1 mmol/L 2 hours after glucose intake. In 1997, the ADA revised the criteria of the WHO and the National Diabetes Data Group (NDDG). Diabetes mellitus can be diagnosed if any of the following conditions are met: (1) Having symptoms of diabetes mellitus, with blood glucose exceeding 11.1 mmol/L (200 mg/dL) at any time. (2) Fasting blood glucose exceeding 7.0 mmol/L (126 mg/dL). (3) An oral glucose tolerance test (OGTT) of 75 grams results in a blood glucose level exceeding 11.1 mmol/L (200 mg/dL) 2 hours after glucose intake. However, the above test results need to be repeated on another day to confirm the diagnosis of diabetes. In addition, the American Diabetes Association defines individuals with fasting blood glucose levels ≥6.1 mmol/L (110 mg/dL) but <7 mmol/L (126 mg/dL) as having impaired fasting glucose (IFG), and considers them to be a high-risk group for type 2 diabetes. The OGTT is not recommended for routine clinical use in the above diagnostic criteria; blood glucose measurements should be repeated on different days for confirmation. Since the ADA (1997) recommendations on the classification and diagnosis of diabetes have not been recognized and recommended by the WHO Expert Committee on Diabetes, the WHO (1995) diagnostic and classification criteria can still be used clinically at present. In 1999, the WHO published new diagnostic criteria, primarily lowering the fasting plasma glucose (FPG) level from 7.8 mmol/L to 7.0 mmol/L to improve diagnostic sensitivity. Diabetes can be diagnosed if one of the following conditions is met: having diabetic symptoms and two or more FPG levels ≥ 7.0 mmol/L; having diabetic symptoms and a blood glucose level ≥ 11.1 mmol/L at any time, or an OGTT 2h blood glucose level ≥ 11.1 mmol/L; or not having diabetic symptoms but, in addition to an FPG ≥ 7.0 mmol/L and an OGTT 2h blood glucose level ≥ 11.1 mmol/L (or a blood glucose level ≥ 11.1 mmol/L at any time), one additional FPG ≥ 7.0 mmol/L or OGTT 2h blood glucose level ≥ 11.1 mmol/L.

III. Clinical Classification According to the WHO 1985 recommendations, diabetes mellitus (DM) is classified into three types. (I) Insulin-dependent DM (IDDM), also known as type 1 diabetes. It is most common in children and adolescents, with onset before the age of 15. The condition is severe, with large fluctuations in blood sugar, and a high risk of ketoacidosis. Because patients have low plasma insulin levels and high glucagon levels, they require lifelong insulin therapy. (II) Non-insulin-dependent DM (NIDDM), also known as type 2 diabetes. It is most common in adults over 40 years of age. Patients are often obese, and often have no symptoms at the onset, frequently being discovered during physical examinations or when obvious diabetic symptoms appear. The disease progresses slowly, and plasma insulin levels are generally within the normal range. Insulin therapy is usually not required in the early and middle stages. Ketoacidosis is more likely to occur under stress. (III) Gestational diabetes mellitus (GDM) refers to DM discovered during pregnancy. During pregnancy, the placenta secretes hormones that counteract insulin (INS), such as cortisone, progesterone, human placental lactogen (HPL), prolactin (PRL), and estrogen. These levels rise rapidly between 24 and 28 weeks of gestation, peaking between 32 and 34 weeks. Therefore, gestational diabetes mellitus (GDM) screening should be performed on every pregnant woman between 24 and 28 weeks. For initial screening, a 50g glucose ingestion test (GCT) is performed 1 hour after ingestion. If the GCT is positive, a standard oral glucose tolerance test (OGTT) is performed for diagnosis. If the OGTT or GCT is negative, a repeat test is performed between 32 and 34 weeks to improve the diagnostic rate of GDM. Because the peak blood glucose level is delayed by 60 minutes during pregnancy, fasting blood glucose (FBG) and hourly blood glucose levels within 3 hours after the OGTT should be measured. A diagnosis of GDM is made if two FBG values ​​are ≥7.0 mmol/L or if two of the four OGTT indicators are higher than normal. GDM-induced hyperglycemia-fetal hyperinsulinemia is prone to complications such as macrosomia, neonatal hypoglycemia, RBC hyperglycemia, hyperbilirubinemia, hypocalcemia, premature birth, and stillbirth. Therefore, early diagnosis of GDM and active blood glucose control during pregnancy are crucial. Newborns should be routinely fed sugar water or milk after birth, and blood glucose should be tested at 2 hours, 6 hours, and 24 hours after birth to prevent and treat GDM as early as possible. Strengthen maternal and neonatal health management. (IV) Specific types of diabetes, such as lipoatrophic diabetes.