Description:
The HbA1c (hemoglobin A1c) test is a blood test used to monitor the status of a patient’s diabetes.


HbA1c provides a patient’s average blood sugar control over a 6-12 week period and is used in conjunction with home blood sugar monitoring to make adjustments in the patient’s diabetes medications.


Hemoglobin is a substance within red blood cells that carries oxygen throughout your body. When diabetes is not controlled (meaning blood sugar is too high), sugar builds up in the blood and combines with hemoglobin, becoming "glycated." Therefore, the average amount of sugar in the blood can be determined by measuring a hemoglobin A1c level. If glucose levels have been high over recent weeks, the hemoglobin A1c test will be higher. The amount of hemoglobin A1c will reflect the last several weeks of blood sugar levels, typically encompassing a period of 120 days.


People with diabetes should test their HbA1c every three months to monitor whether their blood sugars have reached the target level of control. Those who have good control of their diabetes may be able may be able to test less regularly, but experts recommend checking at least twice a year.


Patients with diseases that affect hemoglobin (such as anemia) may receive abnormal results from an HbA1c test. Other abnormalities that can affect the results of the hemoglobin A1c include supplements such as vitamins C and E and high cholesterol levels. Kidney disease and liver disease may also affect the result of the hemoglobin A1c test.
Tests for:
HbA1c to monitor diabetes status


Symptoms and conditions:
Type 1 Diabetes
  • Frequent urination
  • Unusual thirst
  • Extreme hunger
  • Unusual weight loss
  • Extreme fatigue and irritability


Type 2 Diabetes
  • Any of the type 1 symptoms
  • Frequent infections
  • Blurred vision
  • Cuts/bruises that are slow to heal
  • Tingling/numbness in the hands/feet
  • Recurring skin, gum, or bladder infections 


Analytes measured:
  • HbA1c