The level of glycated hemoglobin (HbA1c) in healthy subjects

Abstract

The synthesis of HbA_1C depends on the concentration of blood glucose to which the erythrocytes are exposed during their life. HbA_1C represents an indicator of the average concentrations of glucose during the last 3–4 months. Glycated hemoglobin is derived from the nonenzymatic addition of glucose to the amino group of hemoglobin. HbA1c is a specific glycated hemoglobin that results from the attachment of glucose to the N-terminal valine of hemoglobin β-chain. There have been some reports about the relationship between age and HbA_1C level; however, it has been unclear. In the present study, we examined whether HbA1C had any clinical significance associated with age. The study population consisted of 31 subject, aged 44–85, who were divided into two groups, one of over 60 years old. Samples of venous blood were collected to dry tubes without anticoagulant and they were centrifuged immediately. In the serum, concentrations of C-reactive protein, lipid profile (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride) and levels HbA1C were measured using standard methods on the ACCENT 200. Determination of HbA1C was based on the interaction of antigen and antibody to direct determination of the HbA_1C concentration in whole blood. The mean value of HbA_1C in the examined population is 4.5% without significant differences between males and females. We noticed a significant positive correlation between HbA_1C and glucose, CRP, BMI and hemoglobin. The correlation analyses of the variables were carried out using the Spearman test. There was no correlation between age and HbA_1C in the whole population but in the group of over 60 the correlation was present. In this study, the likelihood of elevated HbA_1C levels increased with levels of glucose as an effect of aging thus glycation may play an independent role in aging. These findings suggest an association between glycemic and its effect on aging.