Glycosylated hemoglobin measurement is used to evaluate the long-term control of blood glucose concentrations in diabetic patients, in the diagnosis of diabetes mellitus, and in the detection of patients at increased risk of developing diabetes (prediabetes).
Glycosylated hemoglobin represents the blood glucose bound to hemoglobin (Hb) and includes three forms: HbA1a, HbA1b, and HbA1c. Glycosylated hemoglobin HbA1c is formed as hemoglobin, is glycosylated gradually throughout the 120 days of life of the red blood cells, and forms the largest part of the three glycosylated fractions of hemoglobin. The amount of glycosylated hemoglobin stored in erythrocytes depends on the amount of glucose available. Glycosylated hemoglobin HbA1c is a very good estimate of how well blood glucose levels have been monitored over the past 3-4 months. Hyperglycaemia in diabetic patients is the most common cause of increased HbA1c.
Glycosylated hemoglobin cannot be used to monitor the control of diabetic patients with chronic renal failure because its levels are significantly lower as a result of the shorter life span of red blood cells in these patients.
Possible Interpretations of Pathological Values
- Increase: Diabetes mellitus, glucosuria, hyperglycemia, polycystic ovary syndrome. False elevated values can be observed in fetal-maternal transfusion, hemodialysis, hereditary persistence of fetal hemoglobin, neonates, and during pregnancy.
- Decrease: Slightly reduced values may be observed in anemia (hemolytic, malignant, sickle cell), chronic blood loss, splenectomy, renal failure (chronic), thalassemia, or medical monoclonal antibody use.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.