What is the significance of A1C in diabetes care. How does the A1C test work. What are the target A1C levels for diabetics. What factors can interfere with A1C test results. How often should diabetics have their A1C levels checked.

What is Hemoglobin A1C and Its Importance in Diabetes?

Hemoglobin A1C, also known as glycated hemoglobin, glycosylated hemoglobin, HbA1c, or simply A1C, is a crucial marker in diabetes management and diagnosis. This test provides valuable insights into a person’s average blood glucose levels over the past 90 days, expressed as a percentage.

The A1C test’s significance lies in its ability to:

• Evaluate long-term glucose control
• Diagnose diabetes
• Assess the risk of diabetes-related complications
• Guide treatment decisions

How does the A1C test work?

The A1C test measures the amount of glycated hemoglobin in red blood cells. Hemoglobin, the protein responsible for blood’s red color, carries oxygen throughout the body. When blood glucose levels are elevated, glucose molecules attach to hemoglobin, creating glycated hemoglobin. Since red blood cells have an average lifespan of about 90 days, the A1C test reflects glucose control over this period.

A1C Test: From Diagnosis to Monitoring Diabetes

The A1C test serves dual purposes in diabetes care: diagnosis and monitoring. Understanding its role in both aspects is crucial for effective diabetes management.

Diagnostic criteria for A1C levels

The American Diabetes Association (ADA) has established the following A1C ranges for diabetes diagnosis:

• Normal: Below 5.7%
• Prediabetes: 5.7% to 6.4%
• Diabetes: 6.5% or higher

It’s important to note that for diagnostic purposes, a venous blood sample processed in a certified laboratory is preferred over point-of-care testing.

Monitoring frequency for diabetics

For individuals with diabetes, regular A1C testing is essential. The ADA recommends:

• Twice a year for stable, well-controlled patients
• Every 3 months for patients with medication changes or poor control

The Impact of A1C Control on Diabetes Complications

Maintaining target A1C levels is crucial for preventing or slowing the progression of diabetes-related complications. The Diabetes Control and Complications Trial (DCCT) provided groundbreaking evidence on the relationship between A1C levels and diabetic complications.

Key findings from the DCCT

• Higher mean A1C levels were the primary predictor of diabetic retinopathy progression
• A1C levels in the 7% range or lower correlated with a 35-76% decrease in microvascular complications
• Lower A1C levels showed long-term benefits in cardiovascular risk and mortality

These findings underscore the importance of maintaining good glycemic control through A1C monitoring and management.

A1C Testing Methods and Accuracy Considerations

A1C testing can be performed using different methods, each with its own considerations for accuracy and reliability.

Point-of-care vs. laboratory testing

A1C tests can be conducted as:

• Point-of-care (POC) tests: Using a STAT analyzer with a capillary fingerstick sample
• Laboratory tests: Using a venous blood sample processed in a certified lab

While POC tests offer quick results, they may be less accurate than laboratory tests. For diagnostic purposes, it’s recommended to confirm POC results with a venous sample processed in a laboratory.

Ensuring test accuracy

To ensure standardized and reliable results, A1C tests should be:

• Performed using a method approved by the National Glycohemoglobin Standardization Program (NGSP)
• Processed in an NGSP-certified laboratory

Even with these precautions, results can vary by up to 0.5% between different laboratories.

Factors Affecting A1C Test Accuracy

Several conditions and factors can influence A1C test results, potentially leading to inaccurate readings. Understanding these factors is crucial for proper interpretation of A1C values.

Conditions that may affect A1C results

• Hemoglobinopathies (e.g., sickle cell anemia, thalassemia)
• Anemia
• Kidney failure
• Liver disease
• Recent blood transfusions

Factors leading to falsely low A1C values

• High altitude
• Pregnancy
• Hemorrhage
• Erythropoietin administration
• Iron supplementation
• Hemolytic anemia
• Chronic kidney failure
• Liver cirrhosis
• Alcoholism

Factors leading to falsely high A1C values

• Iron deficiency anemia
• Vitamin B12 deficiency
• Folate deficiency

In cases where these factors may influence A1C results, healthcare providers should consider alternative methods of glucose monitoring or interpret A1C values with caution.

A1C Targets and Individualized Care in Diabetes Management

While general A1C targets exist, diabetes management should be individualized based on various factors. Understanding the concept of personalized A1C goals is crucial for effective diabetes care.

General A1C targets

The American Diabetes Association suggests the following general A1C targets:

• Less than 7% for most nonpregnant adults with diabetes
• Less than 6.5% for some patients (if achievable without significant hypoglycemia)
• Less than 8% for patients with a history of severe hypoglycemia, limited life expectancy, or advanced complications

Factors influencing individualized A1C goals

When setting A1C targets, healthcare providers consider various factors, including:

• Age and life expectancy
• Duration of diabetes
• Presence of cardiovascular disease or other comorbidities
• Risk of hypoglycemia
• Patient’s ability to manage their diabetes
• Patient preferences and goals

Individualizing A1C targets ensures that diabetes management aligns with each patient’s unique circumstances and needs.

Beyond A1C: Complementary Measures of Glycemic Control

While A1C is a valuable tool in diabetes management, it’s not the only measure of glycemic control. Other methods can provide complementary information for a more comprehensive understanding of glucose levels.

Alternative measures of glycemic control

• Fasting plasma glucose (FPG)
• Oral glucose tolerance test (OGTT)
• Continuous glucose monitoring (CGM)
• Fructosamine test

Benefits of combining A1C with other measures

Using multiple measures of glycemic control can:

• Provide a more complete picture of glucose patterns
• Identify glucose variability not captured by A1C alone
• Help detect hypoglycemic events
• Assist in adjusting treatment plans more precisely

Healthcare providers often use a combination of these methods to tailor diabetes management strategies to individual patient needs.

Interpreting A1C Results: What Do the Numbers Mean?

Understanding A1C results is crucial for both healthcare providers and patients. Proper interpretation of these values can guide treatment decisions and motivate patients to improve their diabetes management.

Relationship between A1C and average blood glucose

A1C values can be translated into estimated average glucose (eAG) levels:

• 5% A1C = 97 mg/dL (5.4 mmol/L)
• 6% A1C = 126 mg/dL (7.0 mmol/L)
• 7% A1C = 154 mg/dL (8.6 mmol/L)
• 8% A1C = 183 mg/dL (10.2 mmol/L)
• 9% A1C = 212 mg/dL (11.8 mmol/L)

This correlation helps patients and providers understand the relationship between A1C percentages and daily glucose readings.

Interpreting changes in A1C values

When evaluating A1C results over time:

• A decrease in A1C indicates improved glucose control
• An increase in A1C suggests worsening glucose control
• Stable A1C values within target range indicate maintained glucose control

It’s important to consider the context of these changes, such as recent lifestyle modifications, medication adjustments, or other health factors.

Strategies for Improving A1C Levels

For individuals aiming to lower their A1C levels, several evidence-based strategies can be effective. These approaches focus on lifestyle modifications and proper medication management.

Lifestyle modifications to lower A1C

• Adopting a balanced, diabetes-friendly diet
• Increasing physical activity and exercise
• Maintaining a healthy weight
• Managing stress through relaxation techniques or counseling
• Getting adequate sleep

Medication management for A1C control

Proper use of diabetes medications is crucial for A1C management:

• Adhering to prescribed medication regimens
• Regularly monitoring blood glucose levels
• Adjusting medications as directed by healthcare providers
• Considering combination therapy when single medications are insufficient

Combining lifestyle changes with appropriate medication use can lead to significant improvements in A1C levels and overall diabetes management.

The Future of A1C Testing and Diabetes Management

As diabetes care continues to evolve, new technologies and approaches are emerging to enhance A1C testing and overall glucose monitoring. These advancements promise to improve the accuracy, convenience, and effectiveness of diabetes management.

Emerging technologies in A1C testing

• Non-invasive A1C monitoring devices
• Improved point-of-care testing accuracy
• Integration of A1C data with continuous glucose monitoring systems

Personalized medicine approaches

Future diabetes care may include:

• Genetic testing to predict individual responses to diabetes treatments
• Artificial intelligence-driven treatment recommendations based on A1C and other health data
• Tailored lifestyle interventions based on individual glucose patterns and A1C trends

These advancements hold the potential to revolutionize diabetes management, making it more precise, personalized, and effective in improving outcomes for individuals with diabetes.

Hemoglobin A1C – StatPearls – NCBI Bookshelf

Introduction

The hemoglobin A1c (glycated hemoglobin, glycosylated hemoglobin, HbA1c, or A1c) test is used to evaluate a person’s level of glucose control. The test shows an average of the blood sugar level over the past 90 days and represents a percentage. The test can also be used to diagnose diabetes.[1]

Hemoglobin is a protein only found in red blood cells. In fact, hemoglobin is what gives blood its bright red coloring. Since red blood cells live about an average of three months, the A1c test will reflect those red blood cells that are present in the bloodstream at the time of the test; this is why the A1c serves as an average of blood sugar control.

The main job of hemoglobin is to carry oxygen from the lungs to all the cells of the body. Hemoglobin becomes glycated or coated with glucose from the bloodstream. The amount of glucose that is present in the blood will attach to the hemoglobin protein, and increased glucose levels will reflect on the surface of the hemoglobin protein, thereby rendering a higher A1c level. [2]

Etiology and Epidemiology

The Diabetes Control and Complications Trial (DCCT)[3] was a landmark trial that provided a wealth of data on A1c and its correlation to blood glucose levels, as well as establishing specific treat to target A1c goals. From the completion of the trial, the National Glycohemoglobin Standardization Program (NGSP) was formed to define a standardized assay that was usable across laboratories.  

The DCCT trial reported that a higher mean A1c level was the dominant predictor of diabetic retinopathy progression. Tighter control shown by levels of HbA1c in the 7% range or lower, were correlated with 35-76% decrease in microvascular complications, like retinopathy, nephropathy and neuropathy, in patients with type 1 diabetes. In addition to the determination of A1c levels predicting progression of microvascular complications, the extension of DCCT into EDIC study showed benefit in the cardiovascular risk and mortality in the longterm for those patients with lower levels of HbA1c. [4][5][6]

Pathophysiology

People with diabetes need to have their A1c checked regularly to determine if their average blood glucose levels are within the target range. The American Diabetes Association (ADA) recommends that the HbA1c is checked twice a year in patients that are stable and well controlled, versus every 3 months in patients with changes in their medications, or not well controlled. [7]

Specimen Requirements and Procedure

The HbA1c test can either be done as a point of care (POC), STAT test, or by sending a sample to a laboratory. The POC test uses a STAT analyzer that evaluates the A1c from a capillary fingerstick. The laboratory test uses a teaspoon of blood drawn from a venous sample into a K2 EDTA (lavender top) tube. The sample gets processed as whole blood.

Diagnostic Tests

The venous sample A1c test may be used as a diagnostic tool in clinical practice when determining diabetes risk or onset. Due to the variability of capillary point of care testing, any A1c done by capillary sample should be confirmed with a venous sample before rendering the diagnosis.

For an HbA1c test to classify as normal, or in the non-diabetic range, the value must be below 5.7 %. Anyone with an HbA1c value of 5.7 % to 6.4 % is considered to be prediabetic, while diabetes can be diagnosed with a HbA1c of 6.5% or higher.

Tests should be sent to a laboratory certified by the NGSP to ensure results are standardized.[8][9]

Testing Procedures

The HbA1c test done by a point of care machine in a doctor’s office may be less accurate than one that is drawn from a venous sample and processed in a laboratory. Typically, the results can vary by different laboratories by as much as 0.5%.

The HbA1c test should be performed using an NGSP-approved method.

Interfering Factors

There are several conditions where the HbA1c test can produce inaccurate results. People diagnosed with sickle cell anemia, thalassemia, anemia, kidney failure, liver disease, or patients receiving blood transfusions can experience altered results due to the longevity of the red blood cell. HbA1c measurement in these patients must be interpreted with caution and should be confirmed with plasma glucose samples to diagnose diabetes.[10]

A falsely low HbA1c value can result from several conditions including high altitude, pregnancy, hemorrhage, blood transfusion, erythropoietin administration, iron supplementation[11], hemolytic anemia, chronic kidney failure, liver cirrhosis, alcoholism, sickle cell anemia[12], and spherocytosis. Vitamin C supplementation can either increase or decrease the HbA1c level depending on the method used for its measurement.[15]

On the other end of the spectrum, a falsely high HbA1c can be due to a lack of available iron in the blood. This condition can result from iron deficiency anemia[13], infection-induced anemia, or tumor-induced anemia. Hemoglobinopathies such as thalassemia and B12 deficiency[11][14] can also cause a falsely high HbA1c. Other causes of falsely high HbA1c levels include hypertriglyceridemia, organ transplantation, and hyperglycation in certain ethnic groups. Medications such as immunosuppressants and protease inhibitors can sometimes lead to a falsely high HbA1c.[10][7][15][16]

Results, Reporting, and Critical Findings

Relationship Between A1c and Glucose Level

The HbA1c percentage equates to an average glucose level in the body that the patient experienced over the past 90 days.[17][18][19]

A1c (%)       Average Blood Glucose (mg/dL)

6                  126

8                  183

10                240

12                298

14                355

Clinical Significance

Hemoglobin A1c serves as an indicator of overall glycemic control and a reflection of the average blood sugar over the past three months.[2]

Quality Control and Lab Safety

Laboratories can use several methods to determine HbA1c. High performance liquid chromatography (HPLC) method is one of the most popular methods because it can eliminate labile components that other methods such as immunoassay or affinity chromatography use. [20]

The point of care (POC) machine is widely used as well to determine HbA1c levels. The variety of POC machines on the market can make it difficult to determine the one best suited for one’s practice. Also, there is a shortage of information comparing the different machines. When using POC testing, one should keep in mind that POC values are often below results reported by a laboratory test, with the mean difference being -0.5%.

Enhancing Healthcare Team Outcomes

All clinicians who look after diabetic patients need to know what HbA1c means. In general, HbA1c provides a measure of the average glucose concentration over three months.

Hemoglobin A1c is often used as an outcome measure to determine if an intervention in a population is successful by showing a decrease in HbA1c by a certain percentage. There is a movement within the medical community to move away from using HbA1c as an exclusive standard of care test to measure patient response to treatment. The Estimated Average Glucose (eAG) and the glucose time in range are the newest proposed methods. [21] These methods use data obtained by continuous glucose monitors (CGMs) that record blood glucose 24 hours a day. They can also give providers a more accurate view of the blood sugar average and fluctuations, but these methods are not available to all patients on a wide-spread basis.

As per ADA guidelines, the levels of HA1c should be measured twice a year in stable patients and at least four times in patients who have glucose fluctuations or those who have had a change in their diabetic treatment. Hemoglobin A1c is one of the preferred diabetes diagnostic tests today. The blood draw can occur at any time, and there are no special handling requirements. However, to ensure that the A1c value is correct, clinicians need to be aware of the causes of false-positive and false-negative results.

Since many patients with diabetes have their condition managed in outpatient clinics, the diabetic nurse should be fully aware of HbA1c values and when to refer the patient to an endocrinologist for further workup and treatment. Pharmacists are also required to fully understand and interpret this test, as they will be involved in glycemic management medication agent selection, dosing, and monitoring.  Both the nurse and/or pharmacist need to inform the treating physician regarding any changes in hemoglobin A1c and verify patient medication compliance. Hemoglobin A1c is a very valuable tool in the fight against diabetes and other glycemic control disorders, but to be effective, it functions best in an interprofessional healthcare team environment. [Level V]

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References

1.

Gilstrap LG, Chernew ME, Nguyen CA, Alam S, Bai B, McWilliams JM, Landon BE, Landrum MB. Association Between Clinical Practice Group Adherence to Quality Measures and Adverse Outcomes Among Adult Patients With Diabetes. JAMA Netw Open. 2019 Aug 02;2(8):e199139. [PMC free article: PMC6694385] [PubMed: 31411713]

2.

Sherwani SI, Khan HA, Ekhzaimy A, Masood A, Sakharkar MK. Significance of HbA1c Test in Diagnosis and Prognosis of Diabetic Patients. Biomark Insights. 2016;11:95-104. [PMC free article: PMC4933534] [PubMed: 27398023]

3.

Diabetes Control and Complications Trial Research Group. Nathan DM, Genuth S, Lachin J, Cleary P, Crofford O, Davis M, Rand L, Siebert C. The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus. N Engl J Med. 1993 Sep 30;329(14):977-86. [PubMed: 8366922]

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Nathan DM., DCCT/EDIC Research Group. The diabetes control and complications trial/epidemiology of diabetes interventions and complications study at 30 years: overview. Diabetes Care. 2014;37(1):9-16. [PMC free article: PMC3867999] [PubMed: 24356592]

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Nathan DM. Realising the long-term promise of insulin therapy: the DCCT/EDIC study. Diabetologia. 2021 May;64(5):1049-1058. [PubMed: 33550441]

6.

Lachin JM, Orchard TJ, Nathan DM., DCCT/EDIC Research Group. Update on cardiovascular outcomes at 30 years of the diabetes control and complications trial/epidemiology of diabetes interventions and complications study. Diabetes Care. 2014;37(1):39-43. [PMC free article: PMC3868002] [PubMed: 24356596]

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American Diabetes Association. 6. Glycemic Targets: Standards of Medical Care in Diabetes-2021. Diabetes Care. 2021 Jan;44(Suppl 1):S73-S84. [PubMed: 33298417]

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American Diabetes Association. 6. Glycemic Targets: Standards of Medical Care in Diabetes-2019. Diabetes Care. 2019 Jan;42(Suppl 1):S61-S70. [PubMed: 30559232]

9.

Qaseem A, Wilt TJ, Kansagara D, Horwitch C, Barry MJ, Forciea MA, Clinical Guidelines Committee of the American College of Physicians. Fitterman N, Balzer K, Boyd C, Humphrey LL, Iorio A, Lin J, Maroto M, McLean R, Mustafa R, Tufte J. Hemoglobin A1c Targets for Glycemic Control With Pharmacologic Therapy for Nonpregnant Adults With Type 2 Diabetes Mellitus: A Guidance Statement Update From the American College of Physicians. Ann Intern Med. 2018 Apr 17;168(8):569-576. [PubMed: 29507945]

10.

Heinemann L, Freckmann G. Quality of HbA1c Measurement in the Practice: The German Perspective. J Diabetes Sci Technol. 2015 May;9(3):687-95. [PMC free article: PMC4604529] [PubMed: 25691655]

11.

Pilla R, Palleti SK, Rayana R, Skss SR, Abdul Razzack A, Kalla S. Glycated Haemoglobin (HbA1c) Variations in Nondiabetics With Nutritional Anemia. Cureus. 2020 Nov 13;12(11):e11479. [PMC free article: PMC7735166] [PubMed: 33329975]

12.

Lacy ME, Wellenius GA, Sumner AE, Correa A, Carnethon MR, Liem RI, Wilson JG, Sacks DB, Jacobs DR, Carson AP, Luo X, Gjelsvik A, Reiner AP, Naik RP, Liu S, Musani SK, Eaton CB, Wu WC. Association of Sickle Cell Trait With Hemoglobin A1c in African Americans. JAMA. 2017 Feb 07;317(5):507-515. [PMC free article: PMC5713881] [PubMed: 28170479]

13.

Guo W, Zhou Q, Jia Y, Xu J. Increased Levels of Glycated Hemoglobin A1c and Iron Deficiency Anemia: A Review. Med Sci Monit. 2019 Nov 07;25:8371-8378. [PMC free article: PMC6857442] [PubMed: 31696865]

14.

Gram-Hansen P, Eriksen J, Mourits-Andersen T, Olesen L. Glycosylated haemoglobin (HbA1c) in iron- and vitamin B12 deficiency. J Intern Med. 1990 Feb;227(2):133-6. [PubMed: 2299304]

15.

Radin MS. Pitfalls in hemoglobin A1c measurement: when results may be misleading. J Gen Intern Med. 2014 Feb;29(2):388-94. [PMC free article: PMC3912281] [PubMed: 24002631]

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Shepard JG, Airee A, Dake AW, McFarland MS, Vora A. Limitations of A1c Interpretation. South Med J. 2015 Dec;108(12):724-9. [PubMed: 26630892]

17.

van ‘t Riet E, Alssema M, Rijkelijkhuizen JM, Kostense PJ, Nijpels G, Dekker JM. Relationship between A1C and glucose levels in the general Dutch population: the new Hoorn study. Diabetes Care. 2010 Jan;33(1):61-6. [PMC free article: PMC2797987] [PubMed: 19808928]

18.

Sayed A, Alyafei F, De Sanctis V, Soliman A, Elgamal M. Translating the HbA1c assay into estimated average glucose values in children and adolescents with type 1 diabetes mellitus. Acta Biomed. 2018 May 23;89(S5):22-26. [PMC free article: PMC6179094] [PubMed: 30049928]

19.

Lai LC. Global standardisation of HbA1c. Malays J Pathol. 2008 Dec;30(2):67-71. [PubMed: 19291914]

20.

Kawano K. Quality control, quality assessment of laboratory tests, HbA1c. Southeast Asian J Trop Med Public Health. 1999;30 Suppl 3:117-21. [PubMed: 10926271]

21.

Saboo B, Kesavadev J, Shankar A, Krishna MB, Sheth S, Patel V, Krishnan G. Time-in-range as a target in type 2 diabetes: An urgent need. Heliyon. 2021 Jan;7(1):e05967. [PMC free article: PMC7814148] [PubMed: 33506132]

Disclosure: Emily Eyth declares no relevant financial relationships with ineligible companies.

Disclosure: Roopa Naik declares no relevant financial relationships with ineligible companies.

What Is The A1c Blood Test? | What Does A1c Stand For?

Medically reviewed by Neka Miller, PhD on March 25, 2021. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

• What Is Diabetes?
• What Are the Symptoms of Diabetes?
• What Is an A1c Blood Test, and What Does A1c Stand For?
• What Does the A1c Test Diagnose?
• How Does HbA1c Testing Work?
• What Does Your A1c Test Result Mean?
• What Are the Treatment Options for Diabetes?
• What Lifestyle Changes Might Be Recommended for Diabetes?
• Is the Everlywell HbA1c Test Right for You?
• Related Content

Understanding your blood sugar level is important, especially if you have diabetes or are at risk of developing it. But how does one actually go about measuring and monitoring this? One effective way: the hemoglobin A1c test—or HbA1c test—which tells you your average blood sugar level over the past 3 months. (You can test your HbA1c at home with the Everlywell HbA1c Test.)

Read on to learn what you need to know about this type of lab test, including how it works and who should take it.

But first, let’s start with an overview of diabetes.

Buy HbA1c Test

What Is Diabetes?

Diabetes is a chronic condition that occurs when your pancreas can’t make insulin or your body can’t properly use it. Insulin plays an important role in energy production. It allows the glucose, or sugar, from your food to pass through the bloodstream to reach your body’s cells and produce energy.

When your body has trouble making or using insulin, it can cause your blood glucose level to increase. Over time, this can contribute to the development of prediabetes or diabetes (type 1 or type 2 diabetes).

• Prediabetes means you have a higher-than-average blood glucose level, but it’s not quite high enough to be indicative of diabetes. But having prediabetes does mean you’re at a significantly higher risk of developing diabetes.
• Type 1 diabetes means your body doesn’t produce enough or any insulin on its own. This condition typically appears when you’re a child, teen, or young adult.
• Type 2 diabetes means your body does produce insulin but it can’t use it properly. This type of diabetes more commonly develops in adults.

Gestational diabetes also exists as a specific type of diabetes that develops during pregnancy. While this condition typically goes away after giving birth, it is associated with a higher risk of you or your child developing type 2 diabetes later in life.

What Are the Symptoms of Diabetes?

There are many different possible symptoms of diabetes, and many of them can seem unrelated at first. If you have the following symptoms, you may want to consider visiting your healthcare provider for further evaluation.

• Excessive thirst and hunger
• Frequent urination
• Unexplained weight loss
• Blurry vision
• Fatigue
• Very dry skin
• Infections and slow-healing wounds
• Numbness or tingling in the hands or feet

If you have type 1 diabetes, you may also have symptoms like stomach pains, nausea, and vomiting.

Also, it’s worth pointing out that over time, untreated or unmanaged diabetes can lead to other health issues and complications, including heart disease, kidney disease, and nerve problems.

What Is an A1c Blood Test, and What Does A1c Stand For?

A1c stands for glycated hemoglobin. The A1c blood test, also known as the HbA1c test, can help with monitoring and diagnosing diabetes. It does so by measuring how much blood sugar is attached to your hemoglobin. Here’s how it works.

As sugar circulates in your bloodstream, some sugar molecules stick to your red blood cells. Specifically, they bind to a red blood cell protein called hemoglobin (hemoglobin is responsible for transporting oxygen molecules from the lungs to other parts of the body). These sugar molecules stay there for the rest of the red blood cell’s lifespan, which is usually about 3 months (your body keeps making new red blood cells as old ones die off). If there’s a lot of sugar in your bloodstream, then a lot of your red blood cells will be covered with sugar molecules.

An HbA1c test measures the percentage of the hemoglobin in your red blood cells that’s covered in sugar—giving you a good idea of your average blood sugar level over the past 3 months.

This way of measuring blood sugar is the key difference between an HbA1c test and a blood glucose meter (commonly called a glucometer). A blood glucose meter can tell you what your blood sugar levels are at the specific moment you take the measurement—in milligrams per deciliter, or mg/dL.

However, blood sugar levels can change quite a lot throughout the day in response to the meals you eat and your physical activity. Since an HbA1c test gives you a 90-day average of your blood sugar, it’s useful for tracking long-term changes and trends in your blood sugar levels.

Related: What is HbA1c?

What Does the A1c Test Diagnose?

In a clinical context in which a healthcare provider considers one’s medical history, symptoms, and risk factors, an A1c test can be a helpful tool for diagnosing prediabetes, type 1 diabetes, and type 2 diabetes. If you already have a diabetes diagnosis, the hemoglobin A1c test can help with monitoring your average blood sugar level and tracking your progress towards improved glycemic control.

While the HbA1c test is valuable in the diagnosis of some forms of diabetes, it can’t diagnose the following types of diabetes:

• Gestational diabetes
• Childhood diabetes

Additionally, it’s important to know that the A1c test is not a replacement for regular blood glucose monitoring (using a glucose meter) in diabetic patients.

How Does HbA1c Testing Work?

The process of getting an A1c blood glucose test is simple. In fact, you don’t even need to fast beforehand (unlike various other kinds of blood sugar tests). You can either make an appointment with your healthcare provider for this test or you can take an at-home test.

• HbA1c testing at your healthcare provider’s office: You’ll provide a blood sample by either undergoing a blood draw or a finger prick. With a blood draw, you’ll have a needle placed in a vein in your arm. Then, your sample will be sent to a lab for testing. With a finger prick, you’ll have your finger pricked with a small lancet.
• At-home HbA1c testing: With options like the Everlywell at-home HbA1c Test, you’ll collect a blood sample—from the convenience and privacy of home—using a quick and easy finger prick. Then, you’ll mail your sample to a laboratory using a prepaid shipping label that’s included with the kit.

What Does Your A1c Test Result Mean?

Once you receive your HbA1c level, either your healthcare provider or at-home test summary can help you understand your test result.

When you receive your HbA1c test results, you’ll notice that it’s reported as a percentage. Below are the typical HbA1c ranges:

• Normal is below 5.7%.
• Prediabetes is between 5.7% and 6.4%
• Diabetes is 6.5% or higher

Note, however, that because these are typical ranges that don’t always reflect a person’s unique health context, it’s best to discuss your A1c test results with your healthcare provider to have a better understanding of what your results mean for you personally.

You can use your A1c number to help you take next steps:

• A normal A1c result usually means you can keep doing what you’ve been doing with regards to blood sugar management—unless your healthcare provider tells you otherwise.
• If your A1c test result suggests that you may have prediabetes or diabetes, you’ll want to visit your healthcare provider for an official diagnosis. In general, you’ll receive a diabetes diagnosis if you have an A1c level of 6. 5% or higher on two different tests.

What Are the Treatment Options for Diabetes?

The type of diabetes that you have and your A1c levels will help determine your diabetes treatment plan. Most diabetes treatment plans will include frequent blood sugar monitoring, insulin, and oral medications.

Routine blood sugar monitoring using a blood glucose monitor is the only way to ensure your average glucose level stays in your target range on a daily basis. Typically, you will monitor your blood sugar more times throughout the day if you’re taking insulin. Your healthcare provider will also likely recommend regular A1c testing as part of your monitoring plan. (Learn more about the Everlywell HbA1c testing option.)

Insulin is critical for people with type 1 diabetes because the body can’t make its own. Additionally, many people with type 2 diabetes or gestational diabetes need insulin therapy. Insulin is typically taken as an injection using a fine needle and syringe or insulin pen. In some cases, an insulin pump is also an option.

Oral medications can often be part of a diabetes treatment plan. Metformin is one of the most common medications for type 2 diabetes. It works by reducing how much sugar your liver releases into your bloodstream. This medication also improves your body’s response to insulin.

What Lifestyle Changes Might Be Recommended for Diabetes?

In addition to these medical interventions, it’s important to manage one’s weight through diet and exercise.

Diet: While there is no specific “diabetes diet,” your healthcare provider may advise you to focus on loading up your plate with fruits, vegetables, whole grains, and lean proteins. These foods tend to be high in fiber and nutrients while being low in fat and calories. They may also recommend cutting back on saturated fats, sugary foods, and refined carbohydrates. You can work with a dietitian to help you design a healthy and balanced diet that can meet your needs.

Exercise: Physical activity helps lower your blood sugar level because exercise moves sugar into your cells to be used for energy. Exercise also improves how your body responds to insulin. To make sure you’re getting enough exercise, aim for at least 150 minutes of moderate physical activity each week (this can be broken down into a routine that works well for you, such as 30 minutes of exercise 5 days a week).

Is the Everlywell HbA1c Test Right for You?

If you’re looking for an easy and effective way to test your A1c, our HbA1c Test can be a great choice. With just a tiny blood sample from a finger prick—collected from the convenience of your home—the Everlywell HbA1c test can help you learn how well your blood sugar has been controlled over the last 90 days.

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What Is Normal HbA1c by Age?

HbA1c vs. Fasting Glucose: Understanding the Similarities and Differences

Prediabetic Range for HbA1c

References

1. About Diabetes. International Diabetes Federation. https://www.idf.org/aboutdiabetes/what-is-diabetes.html. Accessed March 25, 2021.
2. Diabetes Symptoms. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/basics/symptoms.html. Accessed March 25, 2021.
3. Prediabetes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/prediabetes/symptoms-causes/syc-20355278. Accessed March 25, 2021.
4. Diabetes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/diabetes/diagnosis-treatment/drc-20371451. Accessed March 25, 2021.
5. Hemoglobin A1C (HbA1c) Medline Plus. Source. https://medlineplus.gov/lab-tests/hemoglobin-a1c-hba1c-test/. Accessed March 25, 2021.
6. Bonora E, Tuomilehto J. The pros and cons of diagnosing diabetes with A1C. Diabetes Care. 2011;34 Suppl 2(Suppl 2):S184-S190.
7. Katwal PC, Jirjees S, Htun ZM, Aldawudi I, Khan S. The Effect of Anemia and the Goal of Optimal HbA1c Control in Diabetes and Non-Diabetes. Cureus. 2020;12(6):e8431. Published 2020 Jun 3.
8. A1C test. Mayo Clinic. https://www.mayoclinic.org/tests-procedures/a1c-test/about/pac-20384643. Accessed March 25, 2021.

Blood test for glycated hemoglobin A1c

Glycated (or glycosylated) hemoglobin A1c reflects the sugar level over the previous 2-3 months. A test for its amount is one of the markers for the presence of diabetes. Its results are used both for diagnosing the disease and for monitoring its course, monitoring the effectiveness of treatment. The test gives the attending physician the opportunity to identify violations of carbon metabolism, to choose the best therapy.

General

Hemoglobin in erythrocytes is a protein whose main task is to transport oxygen. Among all the varieties of this protein, the A form predominates. One of its components is called A1c. Glucose in the bloodstream is able to spontaneously combine with hemoglobin. The resulting compound is glycated or glycosylated hemoglobin. Its formation directly depends on the amount of sugar. The compound remains stable throughout the life cycle of the erythrocyte. It is formed and broken down daily along with the renewal of red blood cells.

For patients with diabetes, controlling glucose levels and maintaining them at an optimal level makes it possible to avoid the development of complications that can lead to disability and death. Passing this test during a preventive examination makes it possible to detect diabetes in a timely manner.

The characteristic symptoms of diabetes include a constant feeling of thirst, weakness, decreased vision, frequent urination, and a high susceptibility to infectious diseases. If they appear, you should immediately consult a doctor, undergo an examination, and upon confirmation of the diagnosis, begin treatment.

Indications for examination

Patients with diagnosed diabetes are examined every four months (if necessary, more often, the frequency of a blood test for glycated hemoglobin HbA1c is selected by the doctor on an individual basis). Also, the study is prescribed for pregnant women and patients with suspected diabetes for its primary diagnosis. In the absence of health complaints, it is recommended to take the test during a preventive examination at least once every three years. If there is a history of significant bleeding or hemolysis, false results may be obtained. In such cases, it is recommended to consult a doctor before taking the test. If necessary, he will recommend an alternative analysis or this test will be carried out at a later date.

Study preparation

Blood for analysis must be taken strictly on an empty stomach. There is no need to observe a long hungry pause, it is enough not to eat food for three hours before the study. During this period of time, you can drink only sparkling water.

Interpretation of results

Reference values ​​are 4.8 – 5.9%. An increase in readings may indicate diabetes or a pre-diabetic condition. With iron deficiency or after a blood transfusion, the indicators may increase. For a competent interpretation of the results, it is necessary to consult a doctor. Only a specialist can make the correct diagnosis and, if necessary, prescribe treatment.

Glycated hemoglobin: price of analysis

The cost of this test is higher than a standard sugar test. For the most accurate diagnosis, it is recommended to undergo a study on A1c. The test determines the average sugar level for 3 months. Therefore, external factors (for example, stress) do not significantly affect the result. A single test for sugar in this case is less accurate, often it has to be repeated several times.

Hb-What? What does the HbA1C indicator mean?

HbA1c is a scary abbreviation of letters and numbers. A person with type 1 diabetes can experience a drop in energy from just one HbA1c value if it has a value that differs from the norm that the attending physicians have indicated. However, once you understand the importance of monitoring HbA1c and explore options for monitoring it, you will perk up and feel the power of this mysterious alphanumeric combination.

Blood glucose monitoring

There are several methods for measuring blood glucose (BG). You can use one or a combination of several of them, depending on your lifestyle and the advice of your healthcare providers.

1. Fingertip sampling: measurement of the current blood glucose level at a specific point in time (single value).

2. Continuous Glucose Monitoring (CGM): An overview of daily glucose levels that allows you to track glycemic profiles.

3. Time in range (TIR): This quantity was introduced relatively recently and is used primarily by users of CGM devices. It indicates the percentage of time your BGs are in the target range (3.9-10.0 mmol/L or 70-180 mg/dL) over a specified period.

4. HbA1c check: A picture of how well you control your diabetes over a longer period.

HbA1c is a kind of chemical “footprint” that reflects the amount of glucose in your bloodstream over the past 60-90 days (the average lifespan of red blood cells). As a general rule, people with diabetes are advised to aim for an HbA1c level of no more than 6.5% (48 mmol/mol), but your healthcare provider will set a more specific HbA1c target that is calculated specifically for you. This will help minimize the risk of developing diabetes-related complications. ¹ It is important to measure your HbA1c level at least every three months to get a better idea of ​​your progress in diabetes control and, if necessary, adjust your treatment regimen and lifestyle for even better results.

Stop being afraid of these obscure abbreviations! 7 steps to get your HbA1c under control

Precise doses of insulin must be administered to keep HbA1c within the target range and reduce the risk of complications. There are several different ways to administer insulin, including conventional therapy, multiple daily injections, and the most convenient method is using an insulin pump (link). Regardless of which insulin delivery method is best for you, improving blood glucose control and stabilizing HbA1c levels can greatly improve your quality of life ² and give you the opportunity to enjoy your favorite activities.

We’ve put together 7 tips to help you better control your diabetes and HbA1c.

1. Track your BG and HbA1c levels.

It’s hard to know what changes might be needed to improve your treatment if you don’t know your numbers!

2. Avoid hypoglycemia.

Selection and development of a clear algorithm for eliminating the phenomenon of hypoglycemia will allow you, in the appropriate case, not to panic and quickly take control of the situation. For example, you can always carry glucose tablets, juice or hard candy with you. The habitual algorithm will also help to avoid overcompensation, which can lead to an excessive increase in blood glucose levels.

3. Avoid episodes of hyperglycemia.

Blood glucose level can not only decrease, but also increase. An episode of hyperglycemia can occur as a result of incorrect calculation of the amount of carbohydrates consumed, the introduction of an insufficient dose of insulin, or a decrease in the effectiveness of insulin. The goal of controlling hyperglycemia is to prevent diabetic ketoacidosis and to prevent or delay the development of complications associated with high HA levels for a long time.

4. Get sick leave if you need it.

During illness, the body has to cope with increased stress. Often this leads to an increase in the level of HA. ³ An insulin pump allows you to quickly adjust your treatment regimen during illness. If you feel unwell, it is recommended to measure the level of HA more often and conduct a urine test for the content of ketone bodies.

5. Be mindful of your diet and carbohydrate intake.

Understanding how carbohydrate intake affects your blood glucose levels can help you better plan your meals and ultimately control your HbA1c levels. Review the carbohydrate content of your favorite foods and consult with your health care providers to find ways to keep your carbohydrate intake low and your enjoyment of food high.

6. Physical exercise.

Different exercises can have different effects on blood glucose levels, so keep a close eye on your performance each time you try a new activity and be prepared for a possible episode of hypoglycemia.

7. Maintain infusion sites in good condition.

When using an automatic insulin delivery system, such as an insulin pump (link), it is important to pay close attention to maintaining a healthy infusion site and to respect the expiration dates of the insulin, reservoir, and infusion set. Important recommendations include changing the infusion site regularly, checking the condition of the infusion site frequently, installing the system only in approved locations, and maintaining an adequate supply of consumables.

Conclusion

Measuring HbA1c levels is nothing to worry about.