If you are interested in proper nutrition, then you probably thought about what tests you need to take, how to evaluate the results. In order for you to interpret your analyzes correctly, we plan to create a series of materials on the diagnosis of metabolic disorders.

Please note that it is impossible to make a diagnosis and choose a drug therapy in absentia, we also do not urge you to cancel the treatment prescribed by your doctor.

Important: the primary diagnosis of carbohydrate metabolism disorders and, moreover, the diagnosis, based on the indicators of a home glucometer, is not carried out! This device may be useful to you, but it makes sense to talk about it separately.

If you have diabetes mellitus, do not get upset and give up, it will be the most correct for you and will quickly bring sugar back to normal. The only thing is that when taking medications, you will most likely have to adjust their doses.

Let's start with carbohydrate metabolism

So, I am often asked when it is worth starting to take tests and which ones? Let's figure it out.

IFasting glucose blood test (or "blood for sugar")

This is the simplest and first analysis for violations of carbohydrate metabolism, it can be prescribed to you during a medical examination, or when there are certain complaints. The analysis can be taken both from capillary blood from a finger, and from a vein. It doesn’t matter which method you choose, to evaluate the results you should focus on the reference standards of a particular laboratory (they are always indicated in the test form, often on the right), and at the end of the article a table will be given to evaluate the results.

When is it necessary to take this analysis:

1. You have complaints, characteristic of glucose metabolism disorders (dry mouth, increased thirst and urination, increased fatigue, constant hunger, in some cases, sudden weight loss, pustular skin diseases - furunculosis), which are not treated, wounds began to heal poorly, skin itching appeared. Please note that in women - poorly treatable, "causeless" thrush, and in men - potency disorders, may be the only and (or) first complaint when it makes sense to check blood for glucose)
2. You have overweight, BMI>25
3. To all the people aged over 40 years old once every three years, and after 45-50 years more often
4. Do you have signs metabolic syndrome(overweight with accumulation of fat mainly in the waist, high blood pressure, lipid metabolism disorders, possibly coronary heart disease)
5. In family relatives suffer from diabetes
6. All pregnant women, regardless of initial weight (at registration, in the second trimester (25-27 weeks) and closer to childbirth up to 32 weeks)
7. During the period of sharp hormonal changes(puberty, pregnancy, menopause, various endocrine pathologies, such as hypothyroidism)

IIGlucose tolerance test (GTT)

This is a long, but very informative test that allows you to determine the degree of carbohydrate metabolism disorders or diagnose diabetes mellitus. The value of the method increases if the level of insulin in the blood is determined in parallel (this will be discussed in a separate article)

How the test is done:

1. You will take blood on an empty stomach
2. Then, immediately after blood sampling, you will need to drink a glucose solution (75 grams of pure glucose dissolved in 250-300 ml of water)
3. You will be retested in 2 hours
4. Sometimes an analysis is prescribed with intermediate points after 30 minutes and after 3 hours.

What I want to warn you about:

• Be sure to take this study if you have the indications described above. Do not delay analysis for fear of getting bad results. It is better to find out about the problem as early as possible and start with the correction of nutrition and physical activity.
• As a rule, blood from a vein is used (it all depends on the laboratory), but the use of glucometers is strictly prohibited!
• Do not be afraid of an excess load of glucose, from one time you will not develop diabetes if you do not have it, but you can clearly understand the cause, for example, of being overweight or do not miss the onset of diabetes.
• The solution should be drunk within 5 minutes, so try not to stretch the intake of glucose.
• You may feel nauseous during or after the test. Be prepared for this. Take a sliced ​​lemon with you (you can dissolve it in your mouth), it will not distort the glucose readings, but it will help to cope with the overly sweet taste at the time of glucose intake.
• While the test is being conducted, I strongly recommend that you sit quietly in the laboratory, taking a book or an interesting film with you.
• After 2 hours, you may begin to feel dizzy and experience a sharp feeling of hunger (this is due to the release of insulin) - be prepared for this. Take a snack with you, ask one of the relatives to accompany you.

When to take this test:

1. The test is indicated for all persons whose blood test for fasting sugar showed a result of 6.1-6.9 mmol / l. It is this test that reveals the so-called "prediabetes".
2. This study is prescribed for pregnant women in the second trimester, but the test may be prescribed earlier if the woman is at risk (the doctor will take into account the history, overweight and many other factors).
3. As part of the definition of insulin resistance in overweight, metabolic syndrome, with aggravated heredity for diabetes mellitus.

Not everyone knows that glucose levels depend on many reasons, so it’s better to take seriously preparing for the test right away.

How to Prepare for Your Blood Sugar Test or GTT

• When donating blood for sugar on an empty stomach, at least an 8-hour, and preferably a 12-hour fast is implied.
• You can only drink water. Alcohol, juices and sugary drinks are prohibited. Drinking alcohol the night before is not desirable.
• It is often advised to give up sugary toothpaste in the morning and chewing gum.
• Do not smoke before any glucose test. When taking the GTT, do not smoke until the test is completed.
• If you are taking any medications, you should inform your doctor so that the results can be correctly interpreted.
• If you have a cold, or you have some kind of acute infection, it is better to postpone the test, as a false positive result is possible.
• You need to eat 2-3 days before the analysis in your usual mode, you should not artificially limit carbohydrates if you usually eat them. The last meal should also contain carbohydrates (unless you are on an LCHF).
• You should not take an analysis immediately after procedures and serious studies (massage, ultrasound, X-ray, physiotherapy).
• On the eve of the evening and, moreover, in the morning on the day of analysis, you do not need to engage in active sports. It is advisable to spend the previous day and morning as usual. If you were in a hurry to the clinic, walked up the stairs, etc., you should also take a break for 15 minutes in front of the office before going to donate blood. When carrying out GTT, while you are waiting for a second blood sampling, it is better to read calmly, do not try to redo everything in these 2 hours.
• You should not get tested after working the night shift or if you had a very poor night's sleep the night before.
• The female cycle normally has little effect on fasting glucose, however, if the cycle is disturbed and / or in persons with impaired carbohydrate metabolism, fasting blood sugar may increase in the second phase of the cycle.

Interpretation of results:

determination time	Glucose index, mmol/l		next steps
	capillary whole blood (fingerstick)	blood plasma (from a vein)
NORM
on an empty stomach	3,3 5,6	< 6,1	You are healthy, and if you are not overweight, the “liberal version” of LCHF is suitable for you (with the amount of carbohydrates up to 50-60 grams, and with serious physical exertion and up to 100 grams per day, or up to 10% of all calories consumed)
2 hours after GTT	< 7,8	< 7,8
IMPAIRED TOLERANCE TO GLUCOSE
on an empty stomach	5,6-6,1	6,1-7,0	Your condition can be regarded as pre-diabetes, it is best to immediately switch to LCHF, with a restriction of carbohydrates to 20-50 g per day. You can control the process by a glucometer, or by an analysis of glycated hemoglobin after 3 months.
2 hours after GTT	7,8-11,1	7,8-11,1
DIABETES
on an empty stomach	>6,1	>7,0	If you have diabetes, you need to see a doctor right away and get medication, or, depending on the results, you can start with LCHF only while continuing to see a specialist. The amount of carbohydrates should be selected more carefully, taking into account the medications you take, especially with type 1 diabetes, when medications are indispensable. You need a home glucometer.
2 hours after GTT	>11,1	>11,1
random definition	>11,1	>11,1
GESTATIONAL DIABETES MELLITUS
on an empty stomach	>5,1	5, 1-7,0	If you are pregnant, then a very strict LCHF option is not desirable for you, although limiting carbohydrates to 70-100 grams per day can help you control sugar and weight gain. It is advisable for you to have a home glucometer.
1 hour after GTT		>10,0
2 hours after GTT		>8,5
3 hours after GTT		>7,8

If your blood sugar readings are expressed in mg% (or mg/dl, which means the same), then they can be converted to mmol/l using the formula mmol/l = mg%/18, or using an online converter.

III Glycated (glycosylated) hemoglobinHbA1c

The combination of hemoglobin with glucose, which allows you to evaluate the level of glycemia on average over the previous 3 months. Glycated hemoglobin reflects hyperglycemia that occurred during the lifetime of erythrocytes (up to 120 days). Erythrocytes circulating in the blood have different ages. Usually they are guided by an average period of 90 days. The level of glycated hemoglobin is an indicator of the compensation of carbohydrate metabolism during this period. Normalization of the level of glycated hemoglobin in the blood occurs on the 4th - 6th week after reaching a normal glucose level.

This analysis is usually

1. to confirm (or disprove) the presence of diabetes,
2. analysis is necessary in people who already have diabetes to control compensation and to evaluate the effectiveness of therapy.

This analysis in people with diabetes should be performed 2-4 times a year. This test does not replace daily glucose monitoring in established diabetes.

I often recommend that, instead of simply testing your fasting glucose, if you are overweight, you should immediately take a glycated hemoglobin test, which will show your sugar levels over the past three months. If the test results turn out to be "borderline" in the future, the GTT will clarify the situation.

What else is useful for this analysis? There is no need to specially prepare for it, the analysis can be done not on an empty stomach, since the result does not depend on the time the analysis was taken and on food intake.

Interpretation of results:

This indicator in Russian laboratories is usually indicated in%. But in many countries, the mmol / mol indicator is used, you can convert it to percentages using the online calculator on this site.

In healthy people, this level should not exceed 6% . In this case, you can stick to the LCHF depending on your goals, such as weight loss.

Level from 6 to 6.5% considered as a violation of glucose tolerance, i.e. the person is at risk. You should take a GTT test, review your diet as soon as possible and begin to comply with the LCHF (more strict option), and evaluate the results after three months.

Target level HbA1C may differ in patients with diabetes mellitus depending on age, the presence of complications and the risk of hypoglycemia.

If you have high blood sugar and high HbA1C or simply tests with an interval of 3 months show an increased level of glycated hemoglobin twice, then the doctor has the right to diagnose you with diabetes.

Level HbA1C above 6,5% can be considered as diabetes mellitus. You need a glucometer!

At the level HbA1C 6,5%-7,5% - it should be about prescribing drug therapy (usually one drug in small doses if you stick to LCHF).

At the level HbA1C 7,5%-9% - you can’t do without medication yet, you may need to prescribe several medications. Naturally, you need to comply with the LCHF.

At the level HbA1C above 9% it is necessary to prescribe insulin (temporarily, or permanently, your doctor will evaluate in dynamics, depending on your diagnosis and related issues). Carbohydrate restriction you need! You will be able to choose your LCHF option when you learn how to select the dose of insulin depending on the daily glucose values ​​\u200b\u200bbefore meals (according to your glucometer) and on the calculation of the food eaten (often, with strict LCHF, you need to take into account the amount of protein eaten).

As for specific recommendations on the selection of a diet, drug therapy and evaluation of results in people with already diagnosed diabetes mellitus in dynamics, this is a matter of an individual approach, I strongly do not recommend focusing on general recommendations, study your body. Each case of diabetes is different, study your body with love and you will succeed!

To determine the type of diabetes, insulin resistance in the blood, it is necessary to determine a number of other indicators, including C-peptide and insulin.

This will be discussed in a separate article. Follow the publications.

Description

Method of determination Hexokinase.

Material under study Plasma (EDTA, fluoride, tube with gray cap)

Home visit available

Gestational diabetes mellitus or diabetes mellitus of pregnancy is a disorder of glucose tolerance that occurs or is first detected during pregnancy. Pathology affects an average of 7% of pregnant women (estimates vary between 1-14% depending on the population studied and the criteria used). This disorder does not meet the criteria for overt (manifest) diabetes, but it represents a serious medical problem, since it is associated with an increased frequency of pregnancy complications (for mother and fetus), as well as with an increased risk of developing type 2 diabetes in a woman in the future.

Pregnancy is characterized by an increase in insulin resistance, a compensatory increase in insulin secretion, and hyperinsulinemia. In the early period of pregnancy (the first trimester and the first half of the second trimester), fasting and postprandial blood glucose in pregnant women is slightly lower than in non-pregnant women. Insulin resistance usually occurs in the second trimester and increases further during pregnancy. The physiological meaning of this phenomenon is to guarantee an adequate supply of glucose to the fetus, its mechanism is largely associated with the influence of hormones secreted by the placenta. In gestational diabetes, changes in insulin resistance are much more pronounced than in normal pregnancy, and the compensatory increase in insulin secretion is also impaired.

For screening of diabetes mellitus in pregnant women, it is recommended that when a woman first visits a doctor, it is imperative to conduct a study of the level of blood glucose and / or glycated hemoglobin (HbA1c). These studies make it possible to identify overt, i.e., overt diabetes mellitus using one of its criteria (fasting glucose above 7 mmol / l or in a random sample above 11.1 mmol / l, or HbA1c above 6.5%) or assign a pregnant woman in the group of probable gestational diabetes (the criterion is fasting glucose in a pregnant woman above 5.1, but below 7.0 mmol / l).

All pregnant women who did not have disorders of carbohydrate metabolism at an earlier date, between 24 and 28 weeks of pregnancy, a glucose tolerance test is performed.

During the test, the patient should drink a glucose solution within 5 minutes, consisting of 75 g of dry glucose dissolved in 250-300 ml of warm (37-40 ° C) non-carbonated drinking water. Venous blood for research is taken three times:

• on an empty stomach (before taking glucose),
• 1 hour after taking glucose,
• 2 hours after taking glucose.

The time is counted from the start of taking the glucose solution.

At gestation periods of more than 28 weeks, GTT is not performed for pregnant women at INVITRO medical offices.

Literature

1. Clinical guidelines “Algorithms of specialized medical care for patients with diabetes mellitus. Issue 8 "- Diabetes mellitus, 2017, No. 1, p.1-112.
2. American Diabetes Association Standards of Medical Care in diabetes. – Diabetes Care, 2016, Vol. 39, Suppl.1.

Training

Strictly on an empty stomach (from 7.00 to 11.00) after an overnight fasting period of 8 to 14 hours. The recommended term for GTB is 24-28 weeks of gestation, the test can be performed at earlier stages of pregnancy if there is an appropriate indication from the doctor. For GTB-C, the patient must have a referral from the attending physician or medical consultant of the Ministry of Defense / MC indicating the date of issue, the full name of the doctor and his personal signature. During the 3 days preceding the day of the procedure, the patient must:

• follow a regular diet without carbohydrate restriction;
• exclude factors that can cause dehydration of the body (insufficient drinking regimen, increased physical activity, the presence of intestinal disorders);
• refrain from taking medications, the use of which may affect the result of the study (salicylates, oral contraceptives, thiazides, corticosteroids, phenothiazine, lithium, metapiron, vitamin C, etc.).
• For pregnant patients, drugs that affect blood glucose levels (multivitamins and iron preparations containing carbohydrates, glucocorticoids, β-blockers, β-agonists), if possible, should be taken after the end of the test.

ATTENTION!!! Cancellation of drugs is made only after prior consultation of the patient with the doctor!

Indications for appointment

• screening examination of pregnant women to detect gestational diabetes at 24-28 weeks of pregnancy;
• screening of pregnant women up to 24 weeks of gestation in the presence of high risk factors for gestational diabetes.

Interpretation of results

The interpretation of test results contains information for the attending physician and is not a diagnosis. The information in this section should not be used for self-diagnosis or self-treatment. An accurate diagnosis is made by the doctor, using both the results of this examination and the necessary information from other sources: history, results of other examinations, etc.

Units of measurement and conversion factors:

Units of measurement in INVITRO - mmol/l.

Alternate units: mg/dl.

Unit conversion: mg/dL *0.0555=>mmol/L.

Result interpretation:

Previously Used Criteria

Criteria WHO (World Health Organization), 2006: using a 2-hour version of the test with exercise (glucose 75 g) and two blood draws (fasting and 2 hours after exercise), the laboratory criterion for gestational diabetes was considered to be the excess of at least one of the threshold glucose levels - above 7 mmol / l on an empty stomach or above 7.8 mmol / l 2 hours after exercise. New criteria

An international multicenter study on the study of the relationship between hyperglycemia and adverse pregnancy outcomes (HAPO Study - Hyperglycemia and Adverse Pregnancy Outcomes), conducted in 2000–2006, showed that the previously used criteria for diagnosing gestational diabetes mellitus require revision. Based on the findings of this study, new criteria for the diagnosis of gestational diabetes were proposed, which are currently supported by WHO, ADA (American Diabetes Association), as well as the consensus opinion of experts from the Russian Association of Endocrinologists and experts from the Russian Association of Obstetricians and Gynecologists, set out in the Russian National consensus "Gestational diabetes mellitus: diagnosis, treatment, postpartum care" (2012). These recommendations are shown in the table (exceeding any of the 3 thresholds - fasting, 1 hour or 2 hours after exercise is considered as a laboratory criterion for gestational diabetes).

Threshold values ​​of venous blood glucose for the diagnosis of gestational diabetes during a glucose tolerance test with 75 g of glucose.

Glucose tolerance test (OGTT - Oral Glucose Tolerance Test), otherwise called oral glucose tolerance test, used in the diagnosis of diabetes mellitus.

It consists in administering a high dose of glucose to the patient and then studying the reaction of the body - how quickly the blood sugar level is restored and how quickly insulin is released.

Oral glucose tolerance test allows diagnosing metabolic diseases such as diabetes mellitus, as well as diabetes mellitus in pregnant women.

Relationship between glucose and insulin

Glucose plays a very important function in the body - it is the main source of energy. All types of carbohydrates that we consume are converted into glucose. Only in this form they can be used by the cells of the body.

Therefore, during evolution, numerous mechanisms have been formed that regulate its concentration. Many hormones affect the amount of available sugar, one of the most important is insulin.

Insulin is produced in the beta cells of the pancreas. Its functions are primarily to transport glucose molecules from the blood to cells, where they are converted into energy. Besides, hormone insulin stimulates the storage of sugar in cells, and, on the other hand, inhibits the process gluconeogenesis(synthesis of glucose from other compounds, such as amino acids).

All this leads to the fact that the amount of sugar in the blood serum decreases, and in the cells it increases. If there is not enough insulin in the blood or tissues are resistant to its action, the amount of sugar in the blood rises, and the cells receive too little glucose.

In a healthy body, after the administration of glucose, the release of insulin from the cells of the pancreas occurs in two stages. First fast phase lasts up to 10 minutes. Then insulin, accumulated earlier in the pancreas, enters the bloodstream.

IN next phase insulin is made from scratch. Therefore, the process of its secretion takes up to 2 hours after the administration of glucose. However, in this case, more insulin is produced than in the first phase. It is the development of this process that is studied in glucose tolerance test.

Performing a Glucose Tolerance Test

Research can be done in almost any laboratory. First, blood is taken from the cubital vein to study the initial glucose level.

Then, within 5 minutes, you should drink 75 grams of glucose dissolved in 250-300 ml of water (ordinary sugar syrup). The patient then waits in the waiting room for further blood samples to be taken for analysis.

The glucose tolerance test is primarily used to diagnosis of diabetes and also helps in the diagnosis of acromegaly. In the latter case, the effect of glucose on the decrease in growth hormone levels is evaluated.

An alternative to oral glucose is intravenous glucose. During this study, glucose is injected into a vein for three minutes. However, this type of study is rarely done.

The glucose tolerance test itself is not a source of discomfort for the patient. During blood sampling, there is a slight pain, and after taking a glucose solution, you can experience nausea and dizziness, increased sweating, or even loss of consciousness. These symptoms, however, are very rare.

There are different types of glucose tolerance tests, but they all include the following steps:

• fasting blood test;
• the introduction of glucose into the body (the patient drinks a solution of glucose);
• another measurement of blood glucose levels after consumption;
• depending on the test - another blood test after 2 hours.

Most often, 2- and 3-point tests are used, sometimes 4- and 6-point tests. 2 point glucose tolerance test means that the level of glucose in the blood is examined twice - before drinking a glucose solution and an hour after.

The 3-point glucose tolerance test involves another blood sample 2 hours after ingesting the glucose solution. In some tests, the glucose concentration is studied every 30 minutes.

The patient during the study must be in a sitting position, do not smoke or drink liquids, and also report any medications taken or existing infections before the start of the study.

A few days before the test, the subject should not change diet, lifestyle, increase or decrease physical activity.

How to prepare for a glucose tolerance test

The first very important requirement is that the glucose tolerance test should be done on an empty stomach. This means that you should not eat anything for at least 8 hours before taking blood. You can only drink clean water.

In addition, for at least 3 days before the test, you must eat a complete diet (for example, without restricting carbohydrate intake).

It is also necessary to determine with the doctor who ordered the study which of the drugs taken on an ongoing basis can increase glucose levels (in particular, glucocorticoids, diuretics, beta-blockers). Probably, their reception will need to be suspended before execution OGTT studies.

Oral glucose tolerance test in pregnancy

This glucose test is done between 24 and 28 weeks of pregnancy. Pregnancy itself predisposes to the development of diabetes. The reason is a significant increase in the concentration of hormones (estrogens, progesterone), especially after 20 weeks.

This leads to an increase in tissue resistance to the effects of insulin. As a result, the concentration of glucose in the blood serum exceeds the permissible norm, which can be the cause of formidable complications of diabetes mellitus, both in the mother and in the fetus.

Test for glucose tolerance during pregnancy is carried out a little differently. First, a woman should not be on an empty stomach. Arriving at the laboratory, she also donates blood to check the initial level of sugar. Then the expectant mother should drink 50 g of glucose (that is, less) within 5 minutes.

Secondly, the last measurement of the sugar level in the glucose tolerance test during pregnancy is performed 60 minutes after the administration of glucose.

When the test result is greater than 140.4 mg/dL, it is recommended to repeat the test with a 75 g glucose load and glycemic measurements 1 and 2 hours after ingestion of the glucose solution.

Norms of the glucose tolerance test

The result of the glucose tolerance test is presented in the form of a curve - a graph that displays fluctuations in blood glucose levels.

Test norms: in the case of a 2-point test - 105 mg% on an empty stomach and 139 mg% after 1 hour. A result between 140 and 180 mg% may indicate a pre-diabetic condition. A result above 200 mg% means diabetes. In such cases, it is recommended to repeat the test.

If after 120 minutes the result is between 140-199 mg/dL (7.8-11 mmol/L), low glucose tolerance is diagnosed. This is the state of pre-diabetes. You are diagnosed with diabetes when your glucose concentration is greater than 200 mg/dL (11.1 mmol/L) two hours after the test.

In the case of a 50 gram glucose test (during pregnancy), the sugar level after one hour should be less than 140 mg/dl. If higher, it is necessary to repeat the test with 75 g of glucose using all the rules for conducting it. If, two hours after a load of 75 grams of glucose, its concentration is more than 140 mg / dl, gestational diabetes is diagnosed.

It is worth remembering that laboratory standards may vary slightly in different laboratories, so the result of your study should be discussed with the attending physician.

When to do a glucose tolerance test

Glucose tolerance test carried out in cases where:

• there are signs that the person has diabetes mellitus or impaired glucose tolerance;
• after receiving an incorrect result of a fasting glucose test;
• if there are signs of metabolic syndrome (abdominal obesity, high triglycerides, high blood pressure, insufficient HDL cholesterol);
• in pregnant women with an incorrect fasting glucose test result;
• there is a suspicion of reactive hypoglycemia;
• any woman between 24 and 28 weeks pregnant.

The oral glucose tolerance test is important because of its ability to diagnose such a serious disease as diabetes mellitus. Used when, in other studies, the results diagnosing diabetes are inconclusive or when the blood glucose level is in the borderline zone.

The use of a glucose tolerance test is the main and most objective way to detect disorders in the endocrine system up to diagnosing diabetes mellitus. The procedure, as well as preparation for it, is carried out quite quickly and easily, so this study is recommended to be carried out regularly for prevention purposes.

The essence of the method

Every endocrinologist can easily explain what a glucose tolerance test (GTT) is and why it is needed, because this study is the basic method for detecting latent diabetes or other endocrinopathies. The purpose of the test is to measure the patient's blood sugar levels after a sudden glucose load in order to assess the body's ability to cope with this change through the production of insulin. The most common oral glucose tolerance test, in which the patient drinks glucose diluted with water under the supervision of a doctor. However, in some situations, the specialist is forced to resort to intravenous administration of the substance, which is important in the case of people in whom a sweet solution causes nausea, or with patients diagnosed with gastrointestinal diseases (absorption problems).

The determination of the concentration of sugar in the blood occurs by taking blood from a vein, which is carried out in stages in order to assess the dynamics of changes in its composition. The results are obtained in a short time, as laboratory research methods allow you to quickly determine the level of glucose after each sampling. The interpretation of the results depends on the numbers obtained, as well as on the anamnesis, which includes the general condition of the patient and his belonging to one or another risk group.

When is a glucose tolerance test prescribed?

Everyone should know why GTT is needed, because in the modern world, diabetes mellitus affects an increasing number of people every year, affecting children as well. Judging whether this test is mandatory or not is wrong from the point of view of motivation, because taking care of your own health should be a priority for any person, which means that you need to regularly check your condition using laboratory assessment methods. Moreover, GTT should be used to diagnose probable deviations if the patient belongs to the risk group for diabetes mellitus. To date, these categories include:

• patients with impaired glucose tolerance;
• men and women over 40;
• obese patients;
• patients with a history of close relatives who have diabetes;
• patients who have had a heart attack or stroke;
• women who gave birth to a child weighing more than four kg.

If the patient in question falls into one of these categories, they should have regular glucose tolerance testing (at least once a year, according to experts).

The importance of preventive examination is justified by the long latent course of diabetes in the early and middle stages, which is characterized by the absence or minimal presence of symptoms.

Moreover, the clinical picture at this stage is often too vague to suggest that the patient has diabetes mellitus, so a blood sugar test is the first way to detect a progressive deterioration in a person's condition. A timely diagnosis will significantly reduce the likelihood of complications in the future, and will also make it possible to smoothly adjust the patient's lifestyle in the direction of health therapy.

GTT during pregnancy is normal. What is it for, and is there a danger to the fetus?

It's important to know! Pharmacies have been lying for so long! Found a remedy for diabetes, which treats...

To understand why a glucose tolerance test is needed during pregnancy, and whether there is a danger to the fetus, you need to generalize the processes that occur in the body of a woman who is carrying a child. The development of the so-called gestational diabetes, which is transient in nature, is facilitated by a relatively prolonged increase in the blood sugar level of a pregnant woman. Such a deviation is a consequence of the fact that the fetal body is not able to effectively produce insulin in response to incoming glucose in the blood, so the mother's pancreas must produce it in an increased amount. In some cases, the amount of insulin produced is insufficient, resulting in chronic hyperglycemia.

It is also necessary to take a glucose tolerance test during pregnancy for the reason that women bearing a child experience an increased feeling of hunger, which is not always quenched by healthy and low-carbohydrate foods. An analysis of glucose tolerance, contrary to some misconceptions, must be carried out primarily on the basis of concern for the condition of the fetus, and not the mother, because prolonged hyperglycemia can have a detrimental effect on its development. The list of potential problems includes the following situations and pathologies:

• the development of diabetes in a child;
• the occurrence of pathologies of the heart or gastrointestinal tract in the fetus;
• excessively rapid weight gain by the fetus, which can lead to premature birth;
• as a result, the risk of injury to the baby and mother as it moves through the birth canal.

The norms of pregnant women allow for some increase in blood sugar relative to the numbers that are standard for non-pregnant people, however, exceeding the threshold of 5.1 mmol / l suggests gestational diabetes.

In order not to doubt at what time it is better to start conducting GTT, it is better to consult a doctor at the very beginning of pregnancy, after which he, after evaluating the woman’s individual indicators, will draw up a schedule for the tests and issue the necessary recommendations.

When establishing deviations in glucose tolerance, it is sufficient in most cases to correct the patient's diet with a significant reduction in the intake of rapidly digestible carbohydrates: flour and sweet foods. In more complex cases, you will have to resort to the use of insulin preparations, however, during pregnancy, not all of them are allowed for use due to possible side effects.

Contraindications

There are a number of health conditions of the patient, which are direct contraindications to the glucose tolerance test. First of all, we are talking about the sometimes occurring individual intolerance to glucose by the patient, the introduction of which into his body can lead to a sharp and severe reaction. In this case, it is necessary to take measurements without a glucose load, however, it should be noted that sugar intolerance in most situations is the key to its normal blood concentration, since the patient's health does not allow him to consume high-carbohydrate foods.

Another contraindication is any gastrointestinal disease in the acute stage, but in this case it will be enough to replace oral GTT with intravenous. It will be necessary to postpone the test when diagnosing inflammatory and infectious diseases in a patient, as well as acute toxicosis. Finally, it is not recommended to conduct an analysis in the postoperative period and with a strict bed rest prescribed to the patient.

Preparing for a Glucose Tolerance Test

It is not difficult to prepare for a glucose tolerance test, it is enough to do everything according to the instructions from the doctor in order to donate blood correctly and get an objective result. First, three days before the analysis, you should follow a normal diet with an average carbohydrate content (up to 150 grams per day). On the eve of going to the doctor, the last meal should be no later than six in the evening, and the amount of carbohydrates in it must be kept at around 50 grams. The first blood is taken in the morning on an empty stomach, so after the last meal you need to give up food, as well as alcoholic or sugary drinks. During this period, it is enough to drink mineral water without gas, sweeteners and other flavoring and aromatic additives.

So that the data obtained are not distorted, you should also refrain from smoking, and in the morning when washing, you should stop using toothpaste, which may contain glucose or its analogues. All these requirements apply to preparation for a glucose tolerance test during pregnancy, as well as the need to stop taking the following drugs a day before the analysis:

• adrenalin;
• glucocorticoids;
• contraceptives;
• caffeine;
• thiazide diuretics;
• psychotropic drugs;
• antidepressants.

Another important condition for preparation is the avoidance of increased physical exertion and stress, since in these conditions the body consumes glucose more actively, which can distort the result. Finally, GTT is not recommended if the patient has hepatitis, cirrhosis of the liver, the postpartum period, or menstruation.

Survey methodology

The glucose tolerance test is carried out in the morning so as not to force the patient to fast for too long. The method of conducting a glucose tolerance test is that the first thing the patient takes is blood from a vein on an empty stomach and surrenders to calculate the concentration of sugar in it. Five minutes later, a person should drink about a glass of warm water in which glucose is diluted: 75 gr. in the standard case and 1.75 gr. per kg of body weight if the patient is a child. The glucose tolerance test during pregnancy is often complicated by the feeling of nausea that occurs in a woman while taking such a sweet liquid, which is why glucose has to be administered intravenously.

When conducting a glucose tolerance test, it is very important to evaluate the changes in the composition of the blood after the administration of glucose in order to create a dynamic curve and not to miss the likely peak, indicating the presence of latent diabetes. For this reason, the GTT rules state that subsequent blood sampling should be carried out and submitted for analysis every 30 minutes, the last of them two hours after the load of the body with glucose.

All the time the study is being organized, the patient should be calmly in a sitting or lying position, not getting physical activity, not smoking or hypothermia (warming the body actively consumes glucose). Naturally, during the indicated period, no drinks or food should be consumed.

Interpretation of the results

With good tolerance, the blood sugar rate (two hours after the first measurement) should be less than 7.8 mmol / l, otherwise the patient is diagnosed with a violation of the condition.

At values ​​above 11 mmol / l, one can judge the presence of diabetes mellitus in moderate or severe form, which is an indication for the immediate start of insulin therapy and following a strict diet.

In pregnant women, the results of the test are evaluated somewhat differently, taking into account the likelihood of diagnosing gestational diabetes mellitus (GDM). So, on an empty stomach, the sugar level should not exceed 7.0 mmol / l, and confirmation of the presence of transient diabetes is an indicator of 10.0 mmol / l or more one hour after exercise and 8.5 mmol / l or more two hours later. It is important to remember that if the patient's fasting sugar level does not exceed 5.1 mmol / l, further studies can be omitted, since the value is noticeably below the dangerous threshold. It is also pointless to continue the test if 10.0 mmol or more is detected one hour after glucose administration: this indicator is already a sufficient basis for diagnosing GDM.

It remains to add that the final results can be affected by various internal factors of the patient's condition: the presence of endocrinopathies, liver dysfunction, or hypokalemia.

Testing for impaired carbohydrate metabolism will help prevent the progression of some endocrine diseases.

An informative method with a minimum of contraindications is.

It is based on the body's response to the acceptance and processing of glucose into energy for its normal functioning. In order for the results of the study to be reliable, you should know how to properly prepare for it and how to take a glucose tolerance test.

Who needs a glucose tolerance test?

The principle of this method is multiple. First, the analysis is done on an empty stomach, when the body is deficient in a substance.

Then, after certain periods after the intake of a portion of glucose into the blood. This method allows you to follow the dynamics of the degree and time of assimilation of sugar by cells.

According to the results, one can judge the violation of carbohydrate metabolism. Glucose is taken by drinking beforehand. The intravenous route of administration is used for toxicosis, for poisoning, for diseases of the gastrointestinal tract.

Since the purpose of the examination is to prevent metabolic disorders, it is recommended to undergo a glucose tolerance test for patients at risk:

• who have values ​​above 140/90 for a long time;
• patients suffering from gout and;
• women who have undergone during pregnancy;
• patients with, formed after a miscarriage;
• women who had children with defects, who had a large fetus;
• people suffering from and in the oral cavity;
• persons with an indicator of 0.91 mmol / l;

An analysis is also prescribed for patients with an unexplained etiology, for those who have taken diuretics, hormonal drugs for a long time,. Testing is indicated for diabetes mellitus in order to track the dynamics in the treatment of the disease in persons who have hyperglycemia during stress or illness.

Use this method for diagnosing. The test is shown to healthy people over 45 years of age and those who have diabetics in a close family environment. They need to be examined once every two years.

Contraindications for the study include:

• acute infectious diseases, inflammatory processes;
• children's age up to 14 years;
• last trimester of pregnancy;
• exacerbation;
• endocrine ailments: Cushing's disease, acromegaly, hyperactivity, pheochromocytoma;
• recent childbirth;
• liver disease.

The use of steroid drugs, diuretics and antiepileptic drugs can distort the analysis data.

Instructions for preparing patients before donating blood for glucose

Testing should be done on an empty stomach, that is, eight hours before the study. Based on the results of the first analysis, the doctor will judge the nature of the violations, comparing them with subsequent data.

In order for the results to be reliable, patients must comply with a number of conditions for preparing for a glucose tolerance test:

• it is strictly forbidden to take at least three days before the examination;
• on the eve of analysis, one cannot engage in strong;
• do not overheat or overcool;
• should not be three days before testing, and also overeat;
• it is impossible the night before and during the passage of the study;
• must be avoided.

The testing itself requires caution in carrying out, since large amounts of sugar can harm the fetus.

Assign analysis after preliminary testing. If its performance is not too high, GTT is allowed. The maximum dose of glucose is 75 mg.

If infectious diseases are suspected, the examination is canceled. Only test until 32 weeks pregnant. Gestational diabetes is diagnosed at values ​​above 5.1 mmol/L on an empty stomach and 8.5 mmol/L after an exercise test.

How is the study in children?

For children, the dosage is selected differently than for adults - 1.75 g of powder per kilogram of body weight, not more than 75 g. Until the age of fourteen, GTT is not recommended, except for special indications for pathologies in.

How are the results decoded?

A person is given if two tests done at different periods recorded an increase in blood sugar levels.

In humans, a normal value after exercise is considered to be less than 7.8 mmol / l.

If the patient has impaired glucose tolerance, the indicator ranges from 7.9 units to 11 mmol / l. If the result is more than 11 mmol / l, we can talk about diabetes.

Related videos

How to donate blood for sugar with a load during pregnancy:

Diabetes mellitus is one of the diseases for which a glucose tolerance test is recommended to assess the effectiveness of treatment. Even if there is no such diagnosis in the patient's history, the study is indicated for endocrine disorders, thyroid problems, obesity, hypertension, and arthritis.

An analysis is carried out to determine the degree of absorption of glucose by the body. The test is done with a load, the patient drinks a solution of the substance after the first blood sampling on an empty stomach. Then the analysis is repeated.

This method allows you to track the dynamics of metabolic disorders in the patient's body. In a healthy person, blood sugar levels rise and fall to normal levels, while in diabetics it remains consistently high.