Reconsideration of diabetes on January 10, 2003

Reconsideration of diabetes on January 10, 2003

Type 1 diabetes is characterized by insulin deficiency, while Type 2 diabetes is characterized by insulin resistance. The former involves reduced insulin secretion by pancreatic β-cells, whereas the latter involves decreased sensitivity of the body to insulin, despite normal or even elevated insulin concentrations in the blood. Diagnosis of diabetes is based on blood glucose measurements (fasting and postprandial) and urine glucose testing. Postprandial blood glucose testing includes measurements at 0.5, 1, 2, and 3 hours after a meal, known as the oral glucose tolerance test. In healthy individuals, postprandial blood glucose returns to normal within 3 hours, with normal fasting blood glucose ranging from 3.5 to 5.9 mmol/L; the peak postprandial level should remain below 9.1 mmol/L. Quantitative measurement of insulin and C-peptide are key indicators for determining Type 1 or Type 2 diabetes: low insulin levels indicate Type 1, while high or normal levels indicate Type 2. Insulin levels naturally fluctuate before and after meals, providing useful reference points. C-peptide is a precursor to insulin release; when β-cells secrete insulin, C-peptide is released simultaneously, transforming pro-insulin into active insulin, and C-peptide remains freely circulating in the blood. Therefore, C-peptide quantification can reflect changes in blood insulin levels, making it a more precise indicator than insulin quantification itself in diabetic patients receiving insulin therapy. Additionally, glycated hemoglobin and fructosamine measurements can reveal the dynamic state of blood glucose control in diabetic patients. Normal values for glycated hemoglobin are below 7%; for fructosamine, below 3 mmol/L. Elevated glycated hemoglobin indicates blood glucose control status from the previous day; elevated fructosamine indicates blood glucose control status from the day before yesterday.