HbA1C test for laboratory diagnosis of diabetes :
It's one of the commonly used tests to diagnose prediabetes and diabetes, and is also the main test to help you and your health care team manage your diabetes.
Glycated hemoglobin (HbA1C) is a form of hemoglobin that is chemically linked to a sugar. Most monosaccharides, including glucose, galactose and fructose, spontaneously bind with hemoglobin, when present in the bloodstream of humans.
Hemoglobin A1C (HbA1C) test is a blood test that shows what your average blood sugar (glucose) level was over the past two to three months.
The hemoglobin A1C (H A1C) test measures the amount of blood sugar (glucose) attached to your hemoglobin. Hemoglobin is the part of your red blood cells that carries oxygen from your lungs to the rest of your body.Hemoglobin is a protein in your red blood cells that carries oxygen to your body's organs and tissues and transports carbon dioxide from your organs and tissues back to your lungs. It is an important blood test that gives a good indication of how well your diabetes is being controlled in last three months.
The HbA1c test is a simple blood test. The blood can be taken by technician at a pathology laboratory.Usually there is no need to fast before the test .You can eat and drink as normal.
A blood test taken in the morning before you eat anything is a more accurate test. Do not eat or drink anything except water for 8-10 hours before a fasting blood glucose test.
The normal level of A1C:
A normal A1C level is below 5.7%, a level of 5.7% to 6.4% indicates prediabetes, and a level of 6.5% or more indicates diabetes.Thus this test is helpful in diagnosis of prediabetes and diabetes. Within the 5.7% to 6.4% prediabetes range, the higher your A1C, the greater your risk is for developing type II diabetes.
Normal Hb A1C by age
Reference values for HbAC in age-groups:
For individuals aged 20–39 years the upper reference limit (URL) for HbA1C was 6.0% increasing to 6.1% for individuals aged 40–59 years while for people aged ≥60 years the URL was 6.5% .
An HbA1C of 6.5% is recommended as the cut off point for diagnosing diabetes. A value of less than 6.5% does not exclude diabetes diagnosed using glucose tests.
Consistent exercise can lower blood glucose and improve your A1C. It also lowers your risk for heart disease, stroke, and other serious diseases for which diabetics are susceptible. You aim should be 30 minutes of exercise at least five days per week.
Aging is associated with increased HbA1c levels, independently of glucose levels and insulin resistance, and also with decreased HbA1C diagnostic specificity.
Your A1C Result.
A1C % G mg/dL
7 154
8 183
9. 212
10 240
Several factors can falsely increase or decrease your A1C result, including:
•Kidney failure, liver disease, or severe anemia.
•A less common type of hemoglobin that people of African, Mediterranean, or Southeast Asian descent and people with certain blood disorders such as sickle cell anemia or thalassemia may have.
•Certain medicines, including opioids and some HIV medications.
•Blood loss or blood transfusions.
•Early or late pregnancy.
Let your doctor know if any of these factors apply to you, and ask if you need additional tests to find out.
Your A1C Goal:
The goal for most people with diabetes is 7% or less. However, your personal goal will depend on many things such as your age and any other medical conditions. Work with your doctor to set your own individual A1C goal.As such it is very difficult to achieve this goal.
Younger people have more years with diabetes ahead, so their goal may be lower to reduce the risk of complications, unless they often have hypoglycemia that is low blood sugar. People who are older, have severe lows, or have other serious health problems may have a higher goal.
A1C is an important tool for managing diabetes, but it doesn’t replace regular blood sugar testing at home on Glucometer. Blood sugar goes up and down throughout the day and night, which isn’t captured by your A1C.Two people can have the same A1C, one with steady blood sugar levels and the other with high and low swings.
If you’re reaching your A1C goal but having symptoms of highs or lows, check your blood sugar more often and at different times of day at home on Glucometer. Keep track and share the results with your doctor so he can make changes to your treatment plan if needed.
False HbA1C measurements:
Several medications and substances have also been reported to falsely elevate A1C including the lead poisoning, chronic ingestion of alcohol, salicylates, and opioids. Ingestion of vitamin- C may increase A1C when measured by electrophoresis, but may decrease levels when measured by chromatography.
A1C is falsely low in CKD(Chronic kidney Disease): Declining kidney function decreases the reliability of A1C measurements leading to wide variation in the glucose/A1C relationship. This reflects that A1C measurements depend on both blood sugar levels and red blood cell production.
Many kidney diseases usually lower the levels of vitamins and minerals, causing anemia, which ultimately may cause a rise in your A1C level. Uremia, a condition where the blood develops high Urea levels, can also falsely increase A1C level.
A falsely high A1C result can occur in people who are very low in iron; for example, those with iron-deficiency anemia link. Other causes of false A1C results include kidney failure or liver disease.
Vitamin D can lower A1C:
People with type II diabetes who took a vitamin D supplement tended to have lower A1C levels (a measure of long-term blood glucose control) than those who didn't take vitamin D, according to a recent study published in the journal Frontiers in Endocrinology.
Alcohol increases A1C:
Too much drinking, on the other hand (more than three drinks daily), can lead to higher blood sugar and A1C.
The advantage of the A1C test compared to the blood glucose test:
Measurements of hemoglobin A1C (HbA1C) more accurately identify persons at risk for clinical outcomes than the commonly used measurement of fasting glucose(FBS), according to a new study. HbA1C levels accurately predict future diabetes, and they better predict stroke, heart disease and all-cause mortality as well.
The benefits of the HbA1c test:
An HbA1C test is also used to diagnose diabetes, and to keep an eye on your sugar levels if you're at risk of developing diabetes whether you have prediabetes.
The advantages of measuring Hb A1C to assess blood glucose:
HbA1C is a simple blood test that healthcare providers use to:
•Detect prediabetes.
•Help diagnose Type II diabetes.
•Get an idea of how well your management plan is working if you have Type II diabetes or Type I diabetes. Your HbA1C level can help you and your health care provider know if you need to change your treatment strategy.
If your blood sugar levels were high last week, and you adjusted your diabetes treatment plan so that your blood sugar returned to normal, the A1C result may still be high, because it includes the high blood sugar levels from the previous weeks. The A1C test measures the percentage of glycated hemoglobin in your blood.
The difference between A1C and blood sugar:
While blood sugar is measured in milligrams per deciliter (mg/dL), hemoglobin A1c is given as a percentage.When sugar enters your bloodstream, it attaches to hemoglobin, the protein inside your red blood cells th doat carries oxygen from your lungs throughout your body.There is a calculator available on Google to convert HbA1C % in Glucose mg/ 100 ml and vice versa.
Repeat the A1C test as often as your doctor recommends, usually every 1 to 2 years. If you don't have symptoms but if your result shows that you have prediabetes or diabetes, get a second test at an interval of three months to confirm the result.
Signs and symptoms of high A1C are as follows:
•Increased thirst.
•Frequent urination.
•Increased hunger.
•Fatigue.
•Blurred vision.
•Numbness or tingling in the feet or hands.
•Frequent infections.
•Slow-healing sores.
Monitor your HbA1C level regularly,Cotrol diabetes and stay healthy and blessed.Diet; Medicine including insulin ; Exercise and continuous monitoring of blood sugar are the four pillars for controlling diabetic
mellitus.
Information compiled by:
Dr. Bhairavsinh Raol