The patient’s blood glucose management can achieve the standard, and must monitor the corresponding blood glucose indicators. The Chinese Diabetes Guidelines consider blood glucose monitoring to be an important part of diabetes management. Reasonable blood glucose monitoring can help to assess the degree of glucose metabolism disorder in diabetic patients, and develop a reasonable hypoglycemic regimen to evaluate the therapeutic effects of hypoglycemic regimens. Guide the adjustment of the program. What are the current blood glucose monitoring methods, and how to choose these monitoring methods reasonably? (Because venous blood glucose is the basic test method, no special introduction is made here.)
The current blood glucose management at home and abroad mainly passes
Glycated hemoglobin (HbA1C), glycated albumin (GA), self-glycemic monitoring (SMBG), and continuous blood glucose monitoring (CGM) were performed.
The following will describe these blood glucose monitoring methods separately.
- First, let’s talk about the monitoring method of glycated hemoglobin (HbA1C).
HbA1C requires blood sampling for examination, and it does not need an empty stomach. It is convenient to check.
HbA1C can reflect the overall blood glucose in the past 3 months and has a good correlation with the average blood glucose. It is the gold standard for assessing long-term glycemic control status and has a strong predictive value for diabetic complications. It is also an important basis for clinical decision whether or not to adjust treatment. So this should be done in all diabetic patients. The normal reference value for the standard HbA1c assay is 4% to 6%.
All patients with initial onset of diabetes need to be routinely evaluated and then every 3 months to determine if the patient’s blood glucose goals have been met and remained stable. For patients with type 2 diabetes who have stable disease, the frequency of examination can be shortened and 2 tests per year. Patients who are unstable or need enhanced management need to test more frequently than every 3 months.
It should be noted that at present, HbA1C has not been used as a diagnostic standard for diabetes in China. This is mainly due to the fact that the detection instruments in different places are not uniform and the difference is large. In addition, for patients with anemia and hemoglobin abnormalities, the test results of HbA1c are unreliable. Like the Qinghai-Tibet Plateau where I work now, most people have very high glycated hemoglobin, so most people with diabetes have normal or even low HbA1c.
- Glycosylated albumin (GA)
Some places of glycated albumin (GA) become glycated serum protein and glycated serum albumin. Blood tests are also required, but they mainly reflect the overall blood glucose levels of diabetic patients 2 to 3 weeks before the test. Because GA is sensitive to HbA1c in the short-term, and longer than the detection of blood glucose, it is a good indicator to evaluate the short-term glucose metabolism control of patients, especially for the evaluation of the therapeutic effect of diabetic patients. It is also used for diabetes screening and for the identification of stress hyperglycemia caused by acute stress such as trauma, infection, etc. The normal reference value is 11% to 17%.
However, since glycated albumin (GA) is associated with the concentration of albumin, the results of GA are unreliable in patients with diseases such as nephrotic syndrome and cirrhosis that affect the rate of albumin renewal.
- Self-glycemic monitoring (SMBG)
SMBG is part of integrated diabetes management and education and requires SMBG for all diabetic patients. SMBG detection is convenient and rapid, so it has become more and more important in the current monitoring. The frequency is determined according to the patient’s condition, taking into account the effectiveness and convenience. The specific monitoring principles of the China Diabetes Guidelines are as follows:
(1) Patients who are hospitalized due to very poor glycemic control or critical illness should monitor blood glucose 4 to 7 times a day or monitor blood glucose according to treatment needs;
(2) Patients who use lifestyle interventions to control diabetes can adjust their diet and exercise by knowing the effects of diet control and exercise on blood glucose through blood glucose monitoring as needed;
(3) Those who use oral hypoglycemic agents can monitor 2 to 4 times of fasting or 2 h postprandial blood glucose per week;
(4) Patients who use insulin therapy can perform corresponding blood glucose monitoring according to the insulin treatment plan: patients with basal insulin should monitor fasting blood glucose, adjust the dose of bedtime insulin according to fasting blood glucose; use premixed insulin should monitor fasting and pre-dinner blood glucose According to the fasting blood glucose, the insulin dose before dinner is adjusted. According to the blood glucose before dinner, the insulin dose before breakfast is adjusted. After the fasting blood glucose reaches the standard, the postprandial blood glucose is monitored to optimize the treatment plan. In patients with intensive therapy, the frequency of monitoring is relatively high, and needs to be considered before meals, snacks, before going to bed, occasionally after meals, before exercise, when suspected of hypoglycemia, after hypoglycemia treatment until normal blood sugar, and while driving Previously, tests were performed to assess blood glucose levels, so many patients may need to test up to 6-10 times a day. Whether so much monitoring is needed or not needs to be judged by a specialist at the time of the visit.
(5) Monitoring of special populations (perioperative patients, low-glycemic high-risk groups, critically ill patients, elderly patients, type 1 diabetes, GDM, etc.), based on the basic principles of blood glucose monitoring, individualized monitoring programs .
In the self-monitoring of blood glucose, in order to improve patient compliance, it is possible to monitor according to the doctor’s request and learn more about diabetes. At present, most institutions with endocrinology at or above the county level will have regular diabetes education, training and support, and should take the initiative to study.
Since SMBG monitoring is the most convenient, it is very important to choose a good and accurate blood glucose meter. The accuracy and detection method of the blood glucose meter, the quality of the test paper, and the method of use are all related.
At present, the most commonly used method is the glucose oxidase method. Most of the blood glucose meters seen on the market are of this type, and the accuracy is basically the same.
Test strips are very important. Never buy fake or expired test strips, which can cause significant interference with blood glucose measurements.
Do you need calibration? Many current blood glucose meters do not require calibration, or just proofreading of the test strip code. And if it is clearly stated that regular calibration is required, it must be calibrated at the specified time. But even if it is exempt from proofreading, sometimes there will be errors, and a considerable part of the manufacturer has calibration liquid, but it is not needed for individual users. Therefore, if the sudden fluctuation of blood sugar can be compared with other people’s blood glucose meter, or venous blood is checked and calibrated.
Others will ask which of the domestic and foreign or joint venture products to choose. My personal opinion is that if the economic conditions are ok, choose a slightly higher price, whether domestic or foreign. The accuracy of some of the big brands in China is quite good, and the information technology in our country is developing very fast. Most of them are related to the app, which is very convenient. It is not recommended to buy products that are particularly cheap, most of which are accurate at the beginning of the application, but need to be corrected, or there will be large errors after a period of time.
The specific measurement method will not be written here, and will be explained in the future.
- Continuous blood glucose monitoring (CGM)
Continuous blood glucose monitoring (CGM) is a technique for monitoring the change in glucose concentration in the subcutaneous interstitial fluid by a glucose sensor. CGM can provide more comprehensive blood sugar information, understand the characteristics of blood sugar fluctuations, and provide a basis for individualized treatment of diabetes.
At present, there are three main types of CGM, one is real-time CGM, which can continuously report glucose levels; the other is retrospective CGM, which is also to continuously monitor glucose levels, but needs to be taken after the equipment is removed; the last is intermittent scanning CGM ( Intermittently scanning CGM, isCGM).
Most of these monitoring methods can form a visual graph that is very intuitive to display blood sugar, hypoglycemia, and the risk and rate of hyperglycemia. Moreover, some devices have been able to form a closed loop system with the insulin injection system to intelligently regulate insulin infusion.
These three devices are currently measuring the level of glucose in the tissue fluid, so there will be some differences with the actual blood sugar level, some devices need to monitor the level of SMBG for proofreading.
(1) The indications for the real-time CGM system are:
HbA1c <7% of children and adolescents with type 1 diabetes;
HbA1c ≥ 7% of children and adolescents with type 1 diabetes, who are able to use and operate the instrument daily; have the ability to access adult type 1 diabetes patients for daily use;
Pregnant women with type 1 diabetes;
Inpatients with type 2 diabetes who are treated with insulin in a non-intensive care unit;
Perioperative type 2 diabetes patients
For children and adolescents with type 1 diabetes, whether it is multiple daily injections or continuous subcutaneous injections of insulin, real-time continuous blood glucose monitoring should be considered, as there have been clear studies abroad that the benefits of continuous blood glucose monitoring are related to the continued use of the device. . However, children or parents are required to have a certain level of education and can receive diabetes education, training, study and persistence.
(2) The indications for the retrospective CGM system are:
Type 1 diabetes;
Type 2 diabetic patients requiring intensive insulin therapy;
In patients with type 2 diabetes who are treated with hypoglycemia under the guidance of SMBG, one of the following conditions still occurs: 1 unexplained severe hypoglycemia or repeated hypoglycemia, asymptomatic hypoglycemia, nocturnal hypoglycemia; 2 unexplained hyperglycemia, In particular, fasting hyperglycemia; 3 blood sugar fluctuations; 4 patients who deliberately maintain high blood sugar status due to fear of hypoglycemia;
GDM or diabetes with pregnancy;
(3) Intermittently scanning CGM (isCGM)
isCGM (sometimes called “flash” CGM), the earliest product in China is called “instantaneous sense”. It is a measurement method that is close to real-time CGM and has emerged in recent years. Evidence-based medicine has evidence that the use of isCGM can be seen as a substitute for glycemic self-monitoring in patients with diabetes who require frequent blood glucose testing. Since the correction of SMBG is not required, the number of measurements of diabetic patients can be greatly reduced and the pain can be reduced. So I was accepted by many young people who are afraid of pain.