Hemoglobin or Hb is the oxygen-transporting compound in the red blood cells. One of its forms is HbA wherein its specific subtype is HbA1c.
Glucose will slowly bind to Hb and creates what is referred to as glycosylated Hb.
With reference to diabetes, the glycosylated hemoglobin measures have several types, and these include the total glycosylated HbA1 and Hb. However, the HbA1c formed in the glycosylation of HbA is considered as the best standard measure. Faster formation of HbA1c occurs when there are high blood sugar levels, resulting in a higher level of HbA1c.
Hemoglobin A1C and Diabetes
The main fraction of glycohemoglobin or glycosylated hemoglobin wherein glucose is bound, is Hemoglobin A1C. Levels can be tested for the purpose of monitoring the long term control of the condition diabetes mellitus.
The level of hemoglobin A1C increases in the red blood cells of individuals with uncontrolled diabetes mellitus. The level reflects the average level of glucose in the blood over the past four months since glucose is normally attached to hemoglobin for about 120 days; the average life span of red blood cells.
Hemoglobin A1C Levels
The standard amount of hemoglobin A1C levels should not exceed 7%; those that are higher than 9% already represents poor control. Such levels are seldom achieved by diabetics but close monitoring aims to come close to it. It is strongly advised that hemoglobin A1C should be measured every three to six months for people with diabetes mellitus.
The Diabetes Control and Complications Trial (DCCT) discovered that individuals with 7% hemoglobin A1C levels have higher chances of preventing or delaying complications brought by diabetes in the kidneys, eyes and nerves than those with hemoglobin A1C levels 8% or higher. Decreasing the level of hemoglobin A1C, in any amount, can greatly help improve a person’s chance of staying healthy.
Importance of HbA1c
The HbA1c test is vital in evaluating the average glucose levels in the past two to four weeks. It is also the best assessment for knowing the risk of glycemic damage to tissues such as small blood vessels in the kidneys and eyes, as well as in the nerves. Therefore, it is the test that shows the possible risks of diabetes complications.
The United Kingdom Prospective Diabetes Study (UKPDS), Diabetes Control and Complications Trial (DCCT), and other clinical trials have shown that improving HbA1c measures can help reduce the progression and development of nerve, kidney and eye complications in type 1 and type diabetes.
Hemoglobin A1c is highly related with the risk of progression and development of nerve and microvascular complications. These complications happen slowly over time, wherein the younger the person with diabetes is, the higher the risk of having end-stage complications.
Hemoglobin A1C References and Further Reading
University of Michigan; Scientific American; University of Cincinnati.