What is High Blood Sugar?

Hyperglycemia is when the blood glucose level is above the normal range. Hyperglycemia is also one of the "three highs" commonly referred to. In addition, the "two highs" are hypertension and hyperlipidemia. The fasting blood glucose normal value is below 6.1mmol / L, and the two-hour postprandial blood glucose normal value is below 7.8mmol / L. If it is above this range, it is called hyperglycemia.

Basic Information

English name: hyperglycemia
Visiting department: Endocrinology

Multiple groups: Hypertension, hyperlipidemia, family history
Common causes: Insulin deficiency, abnormal regulation of glucose metabolism
Common symptoms: Drink more, eat more, urinate and lose weight

Causes of hyperglycemia

At present, the occurrence of hyperglycemia is mainly related to the following mechanisms:

1. Pancreatic beta cells cannot secrete enough insulin, and alpha cells secrete too much glucagon.

2. Insulin resistance in peripheral tissues including liver, muscle and adipose tissue.

3. Intestinal absorption, intestinal flora and intestines affect blood glucose control hormones, causing their abnormalities.

4. The kidneys excessively absorb sugar.

5. The nervous system's abnormal regulation of glucose metabolism.

Clinical manifestations of hyperglycemia

Increased blood sugar and increased urine sugar can cause osmotic diuresis, which causes symptoms of polyuria; increased blood sugar, large amounts of water loss, and increased blood osmotic pressure; hyperosmosis can stimulate the thirsty thirst center, This leads to symptoms of thirst and excessive drinking; due to the relative or absolute lack of insulin, glucose cannot be used in the body, protein and fat consumption are increased, which causes fatigue and weight loss; in order to compensate for the lost sugar and maintain physical activity, more Eat; this forms the typical "three more and one less" symptom. Symptoms of polydipsia and polyuria in patients with diabetes are directly proportional to the severity of the disease. In addition, it is worth noting that the more the patient eats, the higher the blood sugar, the more sugar is lost in the urine, and the worse the hunger, which eventually leads to a vicious cycle.

"Three more and one less" is the most common clinical manifestation of diabetes, that is, drink more, eat more, polyuria and weight loss. However, some patients with diabetes are currently clinically delayed due to the absence of the typical "three more and one less" symptom. Some patients with type 2 diabetes have no obvious "three more and one less" symptoms. On the one hand, because many diabetic patients are now found through physical examination, blood glucose is only slightly elevated, and has not exceeded or only slightly exceeded the renal glucose threshold. The elimination of sugar is rare and not enough to cause obvious "three more and one less" symptoms. On the other hand, some patients have increased renal glucose threshold. Under normal circumstances, all the glucose is reabsorbed in the kidney and no sugar is excreted in the urine. If the blood glucose is slightly increased, the reabsorption value of the renal tubule will increase accordingly; but when the blood glucose rises to a certain level, it exceeds the maximum value of the renal tubule. In the reabsorption range, part of the glucose will be excreted from the urine, thus forming diuresis. This critical blood glucose value is the renal glucose threshold, and the normal value is 8.8 to 9.9 mmol / L. Kidney disease and other urinary diseases will affect it to varying degrees, and the kidney glucose threshold will increase in most elderly patients. After the renal glucose threshold is increased, the patient does not experience diabetes even if the blood glucose is high. Without glycosuria, osmotic diuresis will not occur, so there will be no polyuria; without a large amount of water loss, the plasma osmotic pressure will change slightly, and the stimulation of the hypothalamic center will be correspondingly reduced, so there will be no thirst and excessive drinking symptoms ; Without diabetes, there is no loss of large amounts of sugar, so there is no obvious hunger, and the symptoms of polyphagia are reduced; without diabetes, the loss of nutrients in the body is reduced, so the degree of weight loss can be reduced accordingly. As a result, these diabetic patients may eventually not have the symptoms of "three more and one less".

Hyperglycemia

1. Blood glucose test for non-pregnant women

Venous blood glucose is the gold standard for diagnosing diabetes or pre-diabetes, but due to the tedious testing of venous blood glucose, it is generally only necessary to measure the blood glucose of the finger blood after diagnosis to become the standard for monitoring blood glucose. You can use a home blood glucose meter for self-blood glucose monitoring at home ( SMBG), its benefits are that it can quickly reflect the actual blood glucose level in the body, better understand the condition, and adjust treatment in time. There is also a dynamic blood glucose monitor (CGM) to get a more detailed understanding of the characteristics of our blood glucose throughout the day.

Good blood glucose control should be to control the blood glucose value within an acceptable range throughout the day. Therefore, the blood glucose monitoring time should include fasting blood glucose, blood glucose before meals, blood glucose 2 hours after meals, blood glucose before bedtime, random blood glucose, and if necessary, blood glucose measurement at 1 to 3 in the morning.

At the same time, for the diabetic patients with different conditions, the selected time point is also focused. For example, newly diagnosed patients often need to regularly monitor blood glucose for a period of time to guide the treatment. Generally, they should be tested 4-7 times a day. When the blood glucose control is relatively stable, monitor 2 to 4 times a month; those who do not meet the blood glucose control should monitor the fasting and postprandial blood glucose at least 4 times at different times of the week. Try a new diet method. Before and after exercise, travel, adjust the insulin dose or frequency. If you have symptoms of hypoglycemia, increase the frequency of monitoring when pregnant or planning to become pregnant.

Diabetic patients can not measure "finger blood glucose" while measuring blood glucose, but also "glycated hemoglobin", so as to reflect the average blood glucose level in the past three months, which is more helpful for doctors to judge the condition. "Finger blood glucose" and "Glycated hemoglobin" are like two grades of a class. "Finger blood glucose" reflects the results of one exam, and "Glycated hemoglobin" reflects the average grade of the class for three months.

The oral glucose tolerance test has a blood glucose level equal to or higher than 11.1 mmol / L two hours after taking glucose, which also meets the diagnostic criteria for diabetes.

2. Pregnant woman blood sugar test

A 75g glucose tolerance test was performed. Pregnant women did not exceed 5.1 mmol / L on an empty stomach, no more than 10.0 mmol / l one hour after a meal, and no more than 8.5 mmol / l two hours after a meal. One of the three items exceeded the standard to diagnose gestational diabetes.

Hyperglycemia diagnosis

Diagnostic criteria

Hyperglycemia includes pre-diabetes and diabetes. Pre-diabetes is a condition in which blood glucose has risen, but has not yet reached the diagnostic criteria for diabetes, and blood glucose is between normal and diabetes. The fasting blood glucose of normal people should be lower than 6.1mmol / L, and the fasting blood glucose for diabetic diagnosis should be equal to or higher than 7.0mmol / L. There is a gap between these two values. Similarly, the two-hour postprandial blood glucose of normal people should be lower than 7.8mmol / L, and the two-hour postprandial blood glucose of diabetic diagnosis should be equal to or higher than 11.1mmol / L. There is also a gap between the two. If a person's blood glucose is exactly within these two gaps, that is to say, fasting blood glucose is between 6.1mmol / L to 7.0mmol / L, and / or two hours after a meal, blood glucose is between 7.8mmol / L to 11.1mmol / L. At this time, the blood glucose at this time is neither normal nor reached the level of diabetes, which is called pre-diabetes.

The diagnosis of diabetes: According to the world's unified standards, fasting blood glucose is equal to or higher than 7.0mmol / L, or two hours after a meal is equal to or higher than 11.1mmol / L, that is to say, the diagnostic criteria for diabetes are reached. Oral glucose tolerance test, blood glucose two hours after taking glucose is equal to or higher than 11.1mmol / L, which also meets the diagnostic criteria for diabetes. For the diagnosis of diabetes, as long as the blood glucose meets the above criteria once, it can be diagnosed. If there are no symptoms, two or more blood glucose must meet the above criteria in different situations to diagnose diabetes.

2. Conversion of blood glucose level

There are two units of blood glucose expression, one is milligram per deciliter (mg / dl), which is the old unit; the other is millimolar / liter (mmol / L), which is the new unit. Although the new system is being promoted, the old system is still used in a certain range. Therefore, it is necessary to know how to switch between the two. The conversion formula of the two units is: mg / dl ÷ 18 = mmol / L; mmol / L × 18 = mg / dl. For example, when 120mg / dl is converted into a value in mmol / L, you need to divide by 18, that is, 120mg / dl ÷ 18 = 6.67mmol / L; when 6.67mmol / L is converted into a value in mg / dl, you need Multiply by 18, which is 6.67mmol / L × 18 = 120mg / dl.

High blood sugar hazard

Short-term, one-time hyperglycemia has no serious damage to the human body. For example, in a state of stress or emotional excitement or high tension, transient hyperglycemia may occur; after eating a large amount of sugars at one time, transient hyperglycemia may also occur; subsequently, blood glucose levels gradually return to normal. However, long-term hyperglycemia will cause lesions in various tissues and organs throughout the body, leading to acute and chronic complications. Such as water loss, electrolyte disorders, nutritional deficiencies, decreased resistance, impaired renal function, neuropathy, fundus lesions, cardiovascular and cerebrovascular diseases, diabetic foot, etc. It is imperative to control high blood sugar.

Hyperglycemia complications

People with diabetes should eat less, but not less than 150 grams of staple food per day. However, if the diabetes is not relieved, the appetite of the patient suddenly decreases. At this time, attention should be paid to whether infection, ketosis and other complications are involved.

Hyperglycemia treatment

First of all, we must remove the causes of blood glucose rise, such as the infection-induced blood glucose rise. The treatment of pre-diabetes and diabetes should follow the principles of the "horse carriage" comprehensive treatment, including a reasonable diet, proper exercise, learning of diabetes knowledge, monitoring of blood sugar and illness, and medication. At the same time, patients with high blood sugar often have problems such as hypertension, hyperlipidemia, and high blood viscosity, which require corresponding treatment.

Hyperglycemia prevention

The principle of preventing hyperglycemia is the same as the principle of treating hyperglycemia. Pay attention to a healthy lifestyle, maintain a reasonable weight, and regularly monitor blood glucose. You can consider using metformin or acarbose in the pre-diabetes period.