What's A "normal" A1c? When Is It Misleading?
By Adithi Gandhi and Jeemin Kwon Why we use A1c, what values are recommended, and what impacts A1c – everything from anemia to vitamins Want more information just like this? Hemoglobin A1c (“HbA1c” or just “A1c”) is the standard for measuring blood sugar management in people with diabetes. A1c reflects average blood sugars over 2 to 3 months, and through studies like DCCT and UKPDS, higher A1c levels have been shown to be associated with the risk of certain diabetes complications (eye, kidney, and nerve disease). For every 1% decrease in A1c, there is significant pretection against those complications. However, as an average over a period of months, A1c cannot capture critical information such as time spent in a target range (70-180 mg/dl) and hypoglycemia (less than 70 mg/dl). This article describes why A1c is used in the first place, as well as factors that can lead to misleadingly high or low values. In a follow-up piece, we will discuss time-in-range, hypoglycemia, hyperglycemia, blood sugar variability, and how to measure and interpret them. Click to jump down to a section: What tools are available if an A1c test is not accurate or sufficient? What is A1c and why is it used? A1c estimates a person’s average blood sugar levels over a 2 to 3-month span. It is the best measure we have of how well blood glucose is controlled and an indicator of diabetes management. Though A1c doesn’t provide day-to-day information, keeping A1c low has been proven to lower the risk of “microvascular” complications like kidney disease (nephropathy), vision loss (retinopathy), and nerve damage (neuropathy). The relationship between A1c and “macrovascular” complications like heart disease is harder to show in clinical trials, but having high blood sugar is a major ris Continue reading >>
Hemoglobin A1c
On This Site Tests: Glucose Tests; Urine Albumin; Urine Albumin/Creatinine Ratio; Fructosamine Conditions: Diabetes In the News: Screening, Diet and Exercise Key Factors in Task Force's New Diabetes Guidelines (2015), Task Force Updates Recommendations for Screening for Pre-Diabetes and Diabetes in Adults (2014), New Report Finds that Diabetes is on the Rise (2014) Elsewhere On The Web American Diabetes Association: Diabetes Basics American Diabetes Association: Risk Test American Association of Diabetes Educators Centers for Disease Control and Prevention: Diabetes Public Health Resource National Diabetes Information Clearinghouse: Prevent diabetes problems - Keep your diabetes under control National Institute of Diabetes and Digestive and Kidney Diseases: Diabetes A to Z National Glycohemoglobin Standardization Program American Diabetes Association – DiabetesPro, estimated Average Glucose, eAG Ask a Laboratory Scientist Your questions will be answered by a laboratory scientist as part of a voluntary service provided by one of our partners, the American Society for Clinical Laboratory Science (ASCLS). Click on the Contact a Scientist button below to be re-directed to the ASCLS site to complete a request form. If your question relates to this web site and not to a specific lab test, please submit it via our Contact Us page instead. Thank you. Continue reading >>
Blood Test: Hemoglobin A1c
en españolAnálisis de sangre: hemoglobina A1c A blood test is when a sample of blood is taken from the body to be tested in a lab. Doctors order blood tests to check things such as the levels of glucose, hemoglobin, or white blood cells. This can help them detect problems like a disease or medical condition. Sometimes, blood tests can help them see how well an organ (such as the liver or kidneys) is working. A hemoglobin A1c test measures how well controlled glucose levels have been for the last 3 months. Glucose is a type of sugar used by the body for energy. Glucose levels and hemoglobin A1c levels can be high if diabetes is not well controlled. When a child has diabetes, hemoglobin A1c levels are followed to see how well medicines are working. If a child with diabetes has a high hemoglobin A1c level, it may mean that medicines need to be adjusted. Sometimes a hemoglobin A1c test is done as part of a routine checkup to screen for problems. How Should We Prepare for a Hemoglobin A1c Test? Your child should be able to eat and drink normally unless also getting other tests that require fasting beforehand. Tell your doctor about any medicines your child takes because some drugs might affect the test results. Wearing a T-shirt or short-sleeved shirt for the test can make things easier for your child, and you also can bring along a toy or book as a distraction. Most blood tests take a small amount of blood from a vein. To do that, a health professional will: put an elastic band (tourniquet) above the area to get the veins to swell with blood insert a needle into a vein (usually in the arm inside of the elbow or on the back of the hand) pull the blood sample into a vial or syringe take off the elastic band and remove the needle from the vein In babies, blood draws are s Continue reading >>
All About The Hemoglobin A1c Test
People with diabetes used to depend only on urine tests or daily finger sticks to measure their blood sugars. These tests are accurate, but only in the moment. As an overall measurement of blood sugar control, they’re very limited. This is because blood sugar can vary wildly depending on the time of day, activity levels, and even hormone changes. Some people may have high blood sugars at 3 a.m. and be totally unaware of it. Once A1C tests became available in the 1980s, they became an important tool in controlling diabetes. A1C tests measure average blood glucose over the past two to three months. So even if you have a high fasting blood sugar, your overall blood sugars may be normal, or vice versa. A normal fasting blood sugar may not eliminate the possibility of type 2 diabetes. This is why A1C tests are now being used for diagnosis and screening of prediabetes. Because it doesn’t require fasting, the test can be given as part of an overall blood screening. The A1C test is also known as the hemoglobin A1C test or HbA1C test. Other alternate names include the glycosylated hemoglobin test, glycohemoglobin test, and glycated hemoglobin test. A1C measures the amount of hemoglobin in the blood that has glucose attached to it. Hemoglobin is a protein found inside red blood cells that carries oxygen to the body. Hemoglobin cells are constantly dying and regenerating, but they have a lifespan of approximately three months. Glucose attaches, or glycates, to hemoglobin, so the record of how much glucose is attached to your hemoglobin also lasts for about three months. If there’s too much glucose attached to the hemoglobin cells, you’ll have a high A1C. If the amount of glucose is normal, your A1C will be normal. The test is effective because of the lifespan of the hemogl Continue reading >>
Hemoglobin A1c Test (hba1c, A1c, Hb1c)
Hemoglobin A1c definition and facts Hemoglobin A1c is a protein on the surface of red blood cells that sugar molecules stick to, usually for the life of the red blood cell (about three months). The higher the level of glucose in the blood, the higher the level of hemoglobin A1c is detectable on red blood cells. Hemoglobin A1c levels correlate with average levels of glucose in the blood over an approximately three-month time period. Normal ranges for hemoglobin A1c in people without diabetes is about 4% to 5.9%. People with diabetes with poor glucose control have hemoglobin A1c levels above 7%. Hemoglobin A1c levels are routinely used to determine blood sugar control over time in people with diabetes. Decreasing hemoglobin A1c levels by 1% may decrease the risk of microvascular complications (for example, diabetic eye, nerve, or kidney disease) by 10%. Hemoglobin A1c levels should be checked, according to the American Diabetic Association, every six months in individuals with stable blood sugar control, and every three months if the person is trying to establish stable blood sugar control. Hemoglobin A1c has many other names such as glycohemoglobin, glycated hemoglobin, glycosylated hemoglobin, and HbA1c. To explain what hemoglobin A1c is, think in simple terms. Sugar sticks to things, and when it has been stuck to something for a long time it's harder to the get sugar (glucose) off. In the body, sugar sticks too, particularly to proteins. The red blood cells that circulate in the body live for about three months before they die. When sugar (glucose) sticks to these red blood cells by binding to hemoglobin A1c, it gives us an idea of how much glucose has been around in the blood for the preceding three months. Hemoglobin A1c is a minor component of hemoglobin to which gl Continue reading >>
A1c Test
Print Overview The A1C test is a common blood test used to diagnose type 1 and type 2 diabetes and then to gauge how well you're managing your diabetes. The A1C test goes by many other names, including glycated hemoglobin, glycosylated hemoglobin, hemoglobin A1C and HbA1c. The A1C test result reflects your average blood sugar level for the past two to three months. Specifically, the A1C test measures what percentage of your hemoglobin — a protein in red blood cells that carries oxygen — is coated with sugar (glycated). The higher your A1C level, the poorer your blood sugar control and the higher your risk of diabetes complications. Why it's done An international committee of experts from the American Diabetes Association, the European Association for the Study of Diabetes and the International Diabetes Federation, recommend that the A1C test be the primary test used to diagnose prediabetes, type 1 diabetes and type 2 diabetes. After a diabetes diagnosis, the A1C test is used to monitor your diabetes treatment plan. Since the A1C test measures your average blood sugar level for the past two to three months instead of your blood sugar level at a specific point in time, it is a better reflection of how well your diabetes treatment plan is working overall. Your doctor will likely use the A1C test when you're first diagnosed with diabetes. This also helps establish a baseline A1C level. The test may then need to be repeated while you're learning to control your blood sugar. Later, how often you need the A1C test depends on the type of diabetes you have, your treatment plan and how well you're managing your blood sugar. For example, the A1C test may be recommended: Once every year if you have prediabetes, which indicates a high risk of developing diabetes Twice a year if Continue reading >>
Hemoglobin A1c (hba1c) Test
If your HbA1c levels are high, it may be a sign of diabetes , a chronic condition that can cause serious health problems , including heart disease , kidney disease , and nerve damage . Other names: HbA1c, A1c, glycohemoglobin, glycated hemoglobin, glycosylated hemoglobin An HbA1c test may be used to check for diabetes or prediabetes in adults. Prediabetes means your blood sugar levels show you are at risk for getting diabetes. If you already have diabetes, an HbA1c test can help monitor your condition and glucose levels. You may need an HbA1c test if you have symptoms of diabetes. These include: A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes. Will I need to do anything to prepare for the test? You don't need any special preparations for an HbA1c test. There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly. HbA1c results are given in percentages. Typical results are below. Your results may mean something different. If you have questions about your results, talk to your health care provider. If you have diabetes, the American Diabetes Association recommends keeping your HbA1c levels below 7%. Your health care provider may have other recommendations for you, depending on your overall health, age, weight, and other factors. Is there anything else I need to know about an HbA1c test? The HbA1c test is not used for gestational diabetes , a type of diabetes that only affects pregnant women, or for diagnosing diabetes in chil Continue reading >>
Hemoglobin A1c Testing: An Introduction
SHARE RATE★★★★★ Hemoglobin A1C testing (A1C) is the test used to measure your average blood glucose level over an extended period of time (2 to 3 months). It is used along with other blood glucose measurements, including random blood sugar testing, fasting blood sugar testing, and oral glucose tolerance testing, that provide a snapshot of your blood glucose at one point in time, to help determine whether your blood sugar is under control. The strength of A1C testing is that it is able to give a larger picture of how blood glucose levels change over days, weeks, and even months. How does A1C testing work? Hemoglobin is an important component of blood (it contains iron and gives blood its red color), responsible for transporting oxygen throughout the body. It is contained within red blood cells that have a lifespan of about 120 days.1 For the purposes of detecting elevated glucose levels and getting a picture of they change over time, hemoglobin A1C is useful because blood glucose tends to attach to hemoglobin. Normally, about 6% of hemoglobin has glucose attached. This combination of hemoglobin and glucose is called glycated hemoglobin or glycohemoglobin. There are different forms of glycohemoglobin, including A1A, A1B, and A1C. Of these, A1C is the most common, making up about two-thirds of glycohemoglobin.1 Advantages of A1C testing over glucose testing in diabetes No need for fasting Cost-effective and standardized test Shows blood glucose levels over time Indicator of future complications Reflects the course of diabetes and need for different levels of treatment How is an A1C test done? The A1C test is a blood test that your healthcare provider will perform. Someone at your doctor’s office or the clinic where you are having the test done will take a sampl Continue reading >>
Effect Of Iron Deficiency Anemia On Hemoglobin A1c Levels
Go to: Abstract Background Iron deficiency anemia is the most common form of anemia in India. Hemoglobin A1c (HbA1c) is used in diabetic patients as an index of glycemic control reflecting glucose levels of the previous 3 months. Like blood sugar levels, HbA1c levels are also affected by the presence of variant hemoglobins, hemolytic anemias, nutritional anemias, uremia, pregnancy, and acute blood loss. However, reports on the effects of iron deficiency anemia on HbA1c levels are inconsistent. We conducted a study to analyze the effects of iron deficiency anemia on HbA1c levels and to assess whether treatment of iron deficiency anemia affects HbA1c levels. Fifty patients confirmed to have iron deficiency anemia were enrolled in this study. HbA1c and absolute HbA1c levels were measured both at baseline and at 2 months after treatment, and these values were compared with those in the control population. The mean baseline HbA1c level in anemic patients (4.6%) was significantly lower than that in the control group (5.5%, p<0.05). A significant increase was observed in the patients' absolute HbA1c levels at 2 months after treatment (0.29 g/dL vs. 0.73 g/dL, p<0.01). There was a significant difference between the baseline values of patients and controls (0.29 g/dL vs. 0.74 g/dL, p<0.01). Conclusions In contrast to the observations of previous studies, ours showed that HbA1c levels and absolute HbA1c levels increased with treatment of iron deficiency anemia. This could be attributable to nutritional deficiency and/or certain unknown variables. Further studies are warranted. Keywords: Iron deficiency anemia, Hemoglobin A1c, HbA1c, Glycated hemoglobin Go to: INTRODUCTION Hemoglobin A1c (HbA1c) is a glycated hemoglobin that can be used as an indicator of a patient's glycemic stat Continue reading >>
Ask The Doctor: What's The Difference Between Blood Sugar And Hemoglobin A1c?
Ask the doctor Q. In your article on blood sugar control, you kept talking about hemoglobin A1c. I measure my blood sugar all the time, but my meter doesn't have a setting for a percentage reading. Is there a simple connection between blood sugar and hemoglobin A1c? A. I'm sorry we confused you. Blood sugar and hemoglobin A1c are connected, but they are different, too. Your blood sugar meter measures the concentration of glucose in the bloodstream at the instant you prick your finger. The reading is in milligrams of glucose per deciliter (a tenth of a liter) of blood, abbreviated as mg/dL. Blood sugar levels vary throughout the day. In people with diabetes, they can range from below 70 mg/dL to above 200. Continue reading >>
- A Novel Intervention Including Individualized Nutritional Recommendations Reduces Hemoglobin A1c Level, Medication Use, and Weight in Type 2 Diabetes
- A Novel Intervention Including Individualized Nutritional Recommendations Reduces Hemoglobin A1c Level, Medication Use, and Weight in Type 2 Diabetes
- Hemoglobin A1c (HbA1c) Test for Diabetes
Pitfalls In Hemoglobin A1c Measurement: When Results May Be Misleading
Go to: DESCRIPTION OF HEMOGLOBIN A1C Hemoglobin is the iron-containing oxygen transport metalloprotein in the red blood cells. Hemoglobin’s structure consists of a tetramer of two pairs of protein molecules: two α globin chains and two non–α globin chains. The α globin genes are HbA1 and HbA2, whereas the non–α globin genes include β, γ, δ.5 The normal adult hemoglobin molecule (HbA) consists of two α and two β chains (α2β2), and makes up about 97 % of most normal human adult hemoglobin.6 Other minor hemoglobin components may be formed by posttranslational modification of HbA. These include hemoglobins A1a, A1b, and A1c. Of these, A1c is the most abundant minor hemoglobin component. A1c is formed by the chemical condensation of hemoglobin and glucose which are both present in high concentrations in erythrocytes. This process occurs slowly and continuously over the life span of erythrocytes, which is 120 days on average. Furthermore, the rate of A1c formation is directly proportional to the average concentration of glucose within the erythrocyte during its lifespan.6 Hence, as levels of chronic hyperglycemia increase, so does the formation of A1c. This makes it an excellent marker of overall glycemic control during the time frame of the 120-day lifespan of a normal erythrocyte. Results of the DCCT and UKPDS studies verified the close relationship between glycemic control measured by A1c and the risk for diabetes-related complications. A1c has been widely accepted as the standard used to measure glycemic control over the previous 3 month period and correlates with patients’ risk for developing diabetes-related complications.7 It is important to remember that A1c represents a weighted mean of glucose levels during the preceding 3 month time period. In ot Continue reading >>
What Is The A1c Test? How Does A1c Relate To Blood Glucose?
Anyone with diabetes will be familiar with finger-prick testing for monitoring blood glucose to see how well they are managing their disease. This kind of regular testing is essential for most people with diabetes, but what role does an occasional hemoglobin A1C blood test play in controlling blood sugars, and how does it work? Contents of this article: What is the A1C test? The abbreviation A1C is used in the US (sometimes with a lower-case 'c' - A1c) and is short for glycated hemoglobin (sometimes called 'glycosylated' hemoglobin or glycohemoglobin). The other abbreviations in use are: HbA1c (widely used internationally) HbA1c Hb1c HgbA1C. The A1C test is a blood test used to measure the average level of glucose in the blood over the last two to three months. This test is used to check how well blood sugar levels are being controlled in a person with diabetes and can also be used in the diagnosis of diabetes.1 Hemoglobin is the protein in red blood cells which is responsible for transporting oxygen around the body. When blood glucose levels are elevated, some of the glucose binds to hemoglobin and, as red blood cells typically have a lifespan of 120 days, A1C (glycated hemoglobin) is a useful test because it offers an indication of longer term blood glucose levels.2 The particular type of hemoglobin that glucose attaches to is hemoglobin A, and the combined result is call glycated hemoglobin. As blood glucose levels rise, more glycated hemoglobin forms, and it persists for the lifespan of red blood cells, about four months.2 Therefore, the A1C level directly correlates to the average blood glucose level over the previous 8-12 weeks; A1C is a reliable test that has been refined and standardized using clinical trial data.3 There are two key things to know about the appl Continue reading >>
- Home blood glucose test: How to test for diabetes at home
- Diabetes and the A1C Test: What Does It Tell You?
- Postprandial Blood Glucose Is a Stronger Predictor of Cardiovascular Events Than Fasting Blood Glucose in Type 2 Diabetes Mellitus, Particularly in Women: Lessons from the San Luigi Gonzaga Diabetes Study
Hemoglobin A1c (hba1c) Test For Diabetes
The hemoglobin A1c test tells you your average level of blood sugar over the past 2 to 3 months. It's also called HbA1c, glycated hemoglobin test, and glycohemoglobin. People who have diabetes need this test regularly to see if their levels are staying within range. It can tell if you need to adjust your diabetes medicines. The A1c test is also used to diagnose diabetes. Hemoglobin is a protein found in red blood cells. It gives blood its red color, and it’s job is to carry oxygen throughout your body. The sugar in your blood is called glucose. When glucose builds up in your blood, it binds to the hemoglobin in your red blood cells. The A1c test measures how much glucose is bound. Red blood cells live for about 3 months, so the test shows the average level of glucose in your blood for the past 3 months. If your glucose levels have been high over recent weeks, your hemoglobin A1c test will be higher. For people without diabetes, the normal range for the hemoglobin A1c level is between 4% and 5.6%. Hemoglobin A1c levels between 5.7% and 6.4% mean you have a higher change of getting of diabetes. Levels of 6.5% or higher mean you have diabetes. The target A1c level for people with diabetes is usually less than 7%. The higher the hemoglobin A1c, the higher your risk of having complications related to diabetes. A combination of diet, exercise, and medication can bring your levels down. People with diabetes should have an A1c test every 3 months to make sure their blood sugar is in their target range. If your diabetes is under good control, you may be able to wait longer between the blood tests. But experts recommend checking at least two times a year. People with diseases affecting hemoglobin, such as anemia, may get misleading results with this test. Other things that can Continue reading >>
5 Ways To Lower Your A1c
For some, home blood sugar testing can be an important and useful tool for managing your blood sugar on a day-to-day basis. Still, it only provides a snapshot of what’s happening in the moment, not long-term information, says Gregory Dodell, MD, assistant clinical professor of medicine, endocrinology, diabetes, and bone disease at Mount Sinai Health System in New York City. For this reason, your doctor may occasionally administer a blood test that measures your average blood sugar level over the past two to three months. Called the A1C test, or the hemoglobin A1C test, this provides a more accurate picture of how well your type 2 diabetes management plan is working. Taking the A1C Test If your diabetes is well controlled and your blood sugar levels have remained stable, the American Diabetes Association recommends that you have the A1C test two times each year. This simple blood draw can be done in your doctor's office. Some doctors can use a point-of-care A1C test, where a finger stick can be done in the office, with results available in about 10 minutes. The A1C test results provide insight into how your treatment plan is working, and how it might be modified to better control the condition. Your doctor may want to run the test as often as every three months if your A1C is not within your target range. What the A1C Results Mean The A1C test measures the glucose (blood sugar) in your blood by assessing the amount of what’s called glycated hemoglobin. “Hemoglobin is a protein within red blood cells. As glucose enters the bloodstream, it binds to hemoglobin, or glycates. The more glucose that enters the bloodstream, the higher the amount of glycated hemoglobin,” Dr. Dodell says. An A1C level below 5.7 percent is considered normal. An A1C between 5.7 and 6.4 perce Continue reading >>
Glycolated Hemoglobin Test (a1c)
The glycosylated hemoglobin test (A1c, also called hemoglobin A1c or the glycosylated hemoglobin test) is an important blood test to diagnose diabetes or determine control of your diabetes. It provides an average blood glucose measurement over the past 3 months and is used in conjunction with home glucose monitoring to make treatment adjustments. The normal range for the A1c test is less than 5.7% for people without diabetes, 5.7%-6.4% for those with pre-diabetes. For people with diabetes, it is 6.5% or higher. For diagnostic purposes, two separate A1c tests at 6.5% are positive for diabetes. People with diabetes who are treated with insulin should have this test 4 times a year (every 3 months). The test may be needed more frequently when your diabetes is not well-controlled. However, the test should be performed no more often than every 6 weeks. Those who are not treated with insulin should have this test every 4 to 6 months. If your A1c is 12.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 298. If your A1c is 11.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 269. If your A1c is 10.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 240. If your A1c is 9.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 212. If your A1c is 8.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 183. If your A1c is 7.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 154. If your A1c is 6.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 126. If your A1c is 5.0%: Your average mean daily plasma blood sugar is around this (mg/dl): 97. Continue reading >>
