According to the World Health Organization, 422 million people worldwide have diabetes, the majority living in low-and middle-income countries, and 1.5 million deaths are directly attributed to diabetes each year. Both the number of cases and the prevalence of diabetes have been steadily increasing over the past few decades. More than 34 million Americans have diabetes (about 1 in 10), and approximately 90-95% of them have type 2 diabetes. Type 2 diabetes most often develops in people over age 45, but more and more children, teens, and young adults are also developing it.
What is A1c test used for?
The A1C test, also known as the hemoglobin A1C or HbA1c test is a simple blood test that measures the average blood sugar levels over the past 3 months. It a test used to identify prediabetes, which raises a person’s risk for diabetes. It can also be used to diagnose diabetes, and it is used to monitor how well diabetes treatment is working overtime. It is also a critical step in formulating a plan for the management of diabetes with the diabetes care team.
The glucose that enters the bloodstream, attaches to hemoglobin, a protein in the red blood cells. Everybody has some sugar attached to their hemoglobin, and the higher the blood sugar levels, the more glucose is attached to the hemoglobin. The A1C test measures the percentage of the red blood cells that have sugar-coated hemoglobin.
Who should get tested for A1c?
The CDC recommends the following people to test for A1c:
An adult over age 45, or if under 45, and overweight, and have one or more risk factors for prediabetes or type 2 diabetes.
An adult over 45 with normal A1c levels but, have risk factors, or have ever had gestational diabetes, to repeat the A1C test every 3 years.
Adults with pre-diabetes.
Adults with diabetes and also being managed for diabetes:
How do you interpret the A1c results?
According to the American Diabetes Association, 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. Within the 5.7% to 6.4% prediabetes range, the higher the A1C, the greater the risk is for developing type 2 diabetes.
A1C result can also be reported as eAG or estimated average glucose. eAG is similar to the readings seen with a glucometer but the values are usually higher than the glucometer readings because glucometer tests are usually done earlier and before breakfast, unlike the A1c which is done at any time of the day.
An eAG level of 117mg/dl is equivalent to A1c of 5.7%; 117mg/dl to 137mg/dl is equivalent to A1c of 5.7% to 6.4%( prediabetes), while 137mg/dl is equivalent to A1c of 6.5% (used as cut off for diabetes).
While A1c is a good test to use in monitoring results in diabetes, it does not take the place of regular blood glucose monitoring using the glucometer. The glucometer measures fluctuations in the daily control of glucose, which the A1c cannot do. Thus two people may have the same A1c value, but one has a steady blood sugar levels and the other has high and low swings of blood glucose which is associated with more complications.
What can affect the A1c values?
A1c values can be increased or decreased in the following conditions:
- Kidney failure, liver disease, or severe anemia
- Being of African, Mediterranean, or Southeast Asian descent
- Certain blood disorders (such as sickle cell anemia or thalassemia)
- Certain medicines, including opioids and some HIV medications
- Blood loss or blood transfusions
- Early or late pregnancy
What is a dangerous level of A1c?
Increasing A1c levels are associated with poor sugar control and occurrence of more complications of diabetes. The goal A1c in people with diabetes differs for individuals but an average of 7% is usually the target. Values above this are usually not ideal and can lead to several complications. A study among elderly diabetic patients reported that the risk of any end point (complication or death) became significantly higher at A1C of ≥8.0%. A1c <6.0% were associated with increased risk of death among these people.
In summary, A1c levels above 7% are associated with diabetic complications, which begin to increase and become more frequent as it approaches 8% and above.
What complications are associated with high A1c
The complications of diabetes are either acute or occur over a long time (chronic).
The acute complications are:
- Diabetic ketoacidosis (DKA) and
- Hyperosmolar, Hyperglycemic State (HHS)
Both conditions occur as a result of very high glucose in the blood and can cause loss of consciousness, coma, and death. DKA occurs more in type 1 Diabetes and in younger people while HHS occurs more in Type 2 diabetes and older people.
The chronic complications of diabetes are many and are seen in various organs, the major organs where these complications are seen are: the eyes (retinopathy), the nervous system (neuropathy), the heart (cardiovascular disease), kidney (nephropathy), and brain (stroke). They cause:
- Cardiovascular disease including coronary artery disease with chest pain (angina), heart attack, stroke and narrowing of arteries (atherosclerosis).
- Nerve damage (neuropathy). The high blood glucose damages the nerves and their blood supply and can cause tingling, numbness, burning or pain that usually begins at the tips of the toes or fingers and gradually spreads upward.
- In untreated cases, all sense of feeling in the affected limbs can be lost. Damage to the nerves related to digestion can cause problems with nausea, vomiting, diarrhea or constipation. For men, it may lead to erectile dysfunction.
- Kidney damage (nephropathy). High blood glucose can damage the delicate filtering system of the kidneys. Severe damage can lead to kidney failure or irreversible end-stage kidney disease, which may require dialysis or a kidney transplant.
- Eye damage (retinopathy). Diabetes can damage the blood vessels of the retina (diabetic retinopathy), potentially leading to blindness. Diabetes also increases the risk of other serious vision conditions, such as cataracts and glaucoma.
- Foot damage. Nerve damage in the feet or poor blood flow to the feet increases the risk of various foot complications. Left untreated, cuts and blisters can develop serious infections, which often heal poorly. These infections may ultimately require toe, foot or leg amputation.
- Skin conditions. People with high blood glucose are susceptible to skin problems, including bacterial and fungal infections.
- Hearing impairment. Hearing problems are more common in people with diabetes.
- Alzheimer’s disease. Type 2 diabetes may increase the risk of dementia, such as Alzheimer’s disease. The poorer the blood sugar control, the greater the risk appears to be.
- Depression. Depression symptoms are common in people with high blood glucose. Depression can affect diabetes management.
If you are diabetic or prediabetic, do follow your doctor’s advice on lifestyle and nutrition changes and a diabetic self-management plan and take your medications to avoid a high level of A1c and complications.