What is glycosylated hemoglobin?

Glycosylated hemoglobin is the hemoglobin bound to glucose molecules, it is the substance inside red blood cells that carries oxygen to the cells of the body. Glucose molecules which are a type of sugar present in the blood normal and are essential as they carry energy to tissues and organs become stuck to hemoglobin molecule, this means the hemoglobin has become glycosylated. This is also referred to as hemoglobin A1c or as HbA1c. As a patient’s blood sugar becomes higher, more of the patient’s hemoglobin becomes glycosylated. The glucose remains attached to the hemoglobin for the life of the red blood cell, which is typically around 2 to 3 months. When the level of the latter are very high for a long period of time, and if the level of hemoglobin in the red blood cells has saturated, it will give rise to glycosylated hemoglobin, and the hemoglobin cells will attach themselves longer than 2 to 3 month period.


Why measure the level of glycosylated hemoglobin?

Measuring the level of glycosylated hemoglobin in a patient, is used to monitor the effectiveness of diabetes treatment and the level of glucose present in the blood. This test indicates the average levels of blood glucose over the past 2 to 3 months. The normal level for glycosylated hemoglobin is less than 7% somewhere around 4.0 to 6.0%, however diabetics rarely achieve such levels. Diabetes is a disease in which a person cannot effectively use sugar in their blood. If left untreated, blood sugar levels can be very high, and hence these high sugar level increase risk of complications, such as damage to the eyes, kidneys, heart, nerves, blood vessels, and other organs. Levels above 9% show poor control, and levels above 12% show very poor control. It is recommended that diabetics measure their glycosylated hemoglobin levels in their blood ever 3 to 6 months. However conditions that increase the lifespan of red cells, such as that of splenectomy (the removal of the spleen), falsely increase the levels. On the other hand conditions that decrease the lifespan of red blood cells, such as hemolysis (disruption of the red blood cell membrane), falsely decrease the levels. Lowering the level even from 8% to 7% in a diabetic can have a drastic health change, and increases their chances of stay healthy.


Standard of preparation

Sampling is usually done in the morning in the hospital. There are no special preparations needed for this test. The doctor will advise and recommend if you need to be fasting prior to the blood examination. You should inform your doctor of any medication you are taking prior to the exam, as some medical treatments may interfere with the blood results.


Is the examination painful or dangerous?

The examination is neither painful nor dangerous. The patient may feel a tingling sensation with the entrance of the needle in the arm when blood is being extracted for examination.


How is the exam performed?

The exam consists of a simple blood sample test.