With the change of lifestyle and diet structure, the prevalence of diabetes and pre diabetes in China is increasing year by year. The increasingly heavy disease burden has brought great challenges to improve the prevention and control of chronic diseases and the national health level in China. The Expert Consensus on Screening and Intervention of diabetes High Risk Groups (2022 Edition) (hereinafter referred to as the Consensus) defines diabetes high risk groups as: age ≥ 40 years old; Have a history of pre diabetes, including abnormal glucose tolerance, impaired fasting glucose or both; Overweight (body mass index (BMI) ≥ 24 kg/m2) or obesity (BMI ≥ 28 kg/m2) and/or abdominal obesity: male waist circumference ≥ 90 cm, female waist circumference ≥ 85 cm); Sitting lifestyle; There are type 2 diabetes patients in the first degree relatives; Women with a history of gestational diabetes; Hypertension [systolic blood pressure ≥ 140 mmHg (1 mmHg=0.133 kPa) and/or diastolic blood pressure ≥ 90 mmHg] or undergoing antihypertensive treatment; Abnormal blood lipids [high-density lipoprotein cholesterol ≤ 0.91 mmol/L and/or triglycerides ≥ 2.22 mmol/L] or undergoing lipid-lowering treatment; Patients with coronary atherosclerotic cardiovascular disease; Have a history of temporary steroid diabetes; Patients with polycystic ovary syndrome (PCOS) or clinical conditions related to insulin resistance (such as acanthosis nigra); Long term treatment with antipsychotic drugs or antidepressants.
In 2021, about 537 million adults (20-79 years old) worldwide will have diabetes (1 in 10 people will have diabetes); It is expected that by 2030, this number will rise to 643 million; By 2045, it will rise to 783 million. During this period, the world population is estimated to increase by 20%, while the number of patients with diabetes is estimated to increase by 46%. The Expert Consensus on Pre diabetes Intervention for Chinese Adults (2023 Edition) was released to strengthen the concept of diabetes prevention and further clarify the population and intervention measures that should be focused on. Therefore, rapid assessment can be carried out at the early stage of the disease. Accurate intervention and scientific treatment can avoid disease deterioration or adverse prognosis to the greatest extent. Among them, glycosylated hemoglobin (HbA1c), insulin (INS), and C-peptide (C-P) diabetes related markers play a particularly important role in the monitoring of pre diabetes and disease.
1、 Glycated hemoglobin (HbA1c)
Glycated hemoglobin (HbA1c or A1C) refers to the glucose in the blood that enters the human bloodstream, binds with hemoglobin in red blood cells, and ultimately forms glycated hemoglobin. And once glucose and heme combine, they will not easily separate until red blood cells die, because the lifespan of red blood cells is within 120 days, so glycated hemoglobin reflects the average blood glucose level of the past 2-3 months. At this time, the higher the glucose concentration in the blood, the higher the glycated hemoglobin value will also be. The following are clinical applications:
1. It is used to evaluate the average blood glucose level of patients for 2-3 months: HbA1c has good stability, can accurately reflect the degree of long-term blood glucose control, is not affected by an occasional increase or decrease in blood glucose, and can objectively reflect the average blood glucose level of diabetes patients in recent 2-3 months, playing an important role in blood glucose monitoring.
2. As a diagnostic indicator of diabetes: WHO has suggested to use HbA1c to diagnose diabetes as early as 2011, but before that, due to the large differences in the standardization of HbA1c measurement in different regions of China, the standardized glycosylated hemoglobin test can make the measurement results comparable; The only biological glycated hemoglobin (HbA1c) testing product has obtained NGSP certification! NGSP is currently the highest international authoritative certification body for the standardization level of glycated hemoglobin determination in international evaluation laboratories.
3. It is used to predict the risk of chronic complications of diabetes: the level of HbA1c is closely related to the occurrence of chronic complications of diabetes (especially microvascular complications). The higher the glycosylated hemoglobin, the greater the risk of complications.
4. It is used to evaluate the effectiveness of the treatment plan on blood sugar control: HbA1c can sensitively reflect the blood sugar control effect of diabetes patients, and it is not only used for diagnosis, but also a key indicator for clinical follow-up. If the patient’s blood sugar control is not effective, the concentration of glycated hemoglobin indicators in the body can increase to 2 times or more than normal levels. We often say that HbA1c is the gold standard for diabetes control. In clinical practice, the control level of HbA1c in patients is also used as the basis for adjusting treatment plans.
2、 Insulin
Insulin is produced by the pancreas β A hormone synthesized, stored, and secreted by cells, which has the function of regulating blood sugar. Insulin reduces blood glucose concentration by inhibiting gluconeogenesis in the liver, promoting triglyceride synthesis in adipose tissue, and protein synthesis in muscle. Insulin secretion disorder and insulin resistance are important characteristics of diabetes, among which type I diabetes patients are due to their own islets β Cell function is damaged and insulin secretion is insufficient. Type II diabetes patients have different degrees of insulin resistance and insulin secretion disorders due to complex factors. Insulin measurement can be used to evaluate pancreatic function.
3、 C-peptide
C-peptide, also known as linker peptide, is a type of pancreatic islet β The secretion product of cells, which shares a common precursor with insulin, is proinsulin. One molecule of proinsulin is cleaved into one molecule of insulin and one molecule of C-peptide by the action of pancreatic protease and carboxypeptidase. Because C-peptide is not easily degraded by the liver, measuring C-peptide is a measure of insulin content, which can accurately reflect the function of pancreatic islet cells. During the oral glucose tolerance test, blood can be drawn to measure serum C-peptide levels at 1 hour, 2 hours, and 3 hours after fasting blood glucose load. In normal individuals, C-peptide levels increase to more than three times the baseline level after 60 minutes of glucose intake. The level of C-peptide in type 1 diabetes is extremely low, and the increase of C-peptide after meal in patients with impaired islet function is often less than three times. For patients receiving insulin therapy, measuring blood insulin levels cannot evaluate their own pancreatic function, but C-peptide levels can be measured to evaluate their own pancreatic function β Cellular function.
In recent years, the incidence rate of diabetes is increasing year by year, and type 2 diabetes accounts for more than 90% of all diabetes patients. Therefore, early diagnosis, timely treatment and effective control of type 2 diabetes have received great attention. The newly issued Guidelines for the Prevention and Treatment of Type 2 diabetes in China mentioned that HbA1c has been used clinically as the “gold standard” for assessing long-term blood glucose control, and is also an important basis for clinical decisions on whether to adjust treatment. Blood glucose monitoring is an important part of diabetes management. Its results can help to assess the degree of glucose metabolism disorder in diabetes patients, develop a reasonable hypoglycemic program, reflect the effect of hypoglycemic treatment, and guide the adjustment of the treatment program. The impairment of islet B cell function and insulin resistance are the pathophysiological basis of type 2 diabetes. The measurement of serum insulin and C-peptide can reflect the islet B cell function. The latest Guidelines for the Prevention and Treatment of Type 2 diabetes in China takes HbA1c as the standard for evaluating long-term blood glucose control. Blood glucose monitoring is an important part of diabetes management. The impairment of islet B cell function and insulin resistance are the pathophysiological basis of type 2 diabetes. The determination of insulin and C-peptide in serum can reflect the function of islet B cells. According to the results of fasting blood glucose and OGTT, diabetes can be diagnosed, and the quantitative content of insulin and C-peptide can be used as the classification basis of diabetes.
These indicators and test results are very important for early diagnosis, timely treatment and effective control of type 2 diabetes, which will help improve the quality of life of patients and prevent diabetes related complications. For patients who have been diagnosed with diabetes, regular monitoring of blood glucose, HbA1c, insulin, C-peptide and other indicators is also an important basis for disease management, evaluation of treatment effect and adjustment of treatment plan.
Post time: Jan-19-2024