The clinical usefulness of hba1c and fructosamine in glyacemic control of patients with diabetes mellitus

Background: In recent years measurement of glycated haemoglobin Al (HbA1c) has been widely introduced as a measure of control of diabetes and is used by many diabetologists. However, it is subject to a number of disadvantages. It requires incubation for several hours to remove the unstable intermediate Schiff base, it is quite a time consuming assay to perform and, by comparison with the measurement of other ketoamines, relatively expensive. More recently, a method has been described for the measurement of glycated serum proteins, known as fructosamine, which is based on a colorimetric determination utilizing the reducing properties of fructosamine at high pH. It has the advantage that it is rapid, inexpensive, and can be automated, thus reducing the amount of laboratory time required for the assay. Objectives: The aim of the study is to evaluate the different methods for the glycemic control in diabetic patients. The primary objective is to compare the efficiency of NBT reduction method for estimation of serum fructosamine with HbA1c estimated by ion exchange resin method & secondary objective is an attempt to develop cost effective, manual, dye based method for estimation of serum fructosamine. Method: 57 patients with type 2 DM and 57 controls were enrolled for the study. EDTA blood sample were used for HbA1c by Ion exchange Resin Method. Serum samples were used to detect fructosamine, FBS, PPBS, urea, creatinine, total protein & albumin. For fructosamine NBT Reduction method was used. Results: The average value of HbA1c for cases was 7.82±1.12 and for controls 5.3±0.9. The average value of fructosamine for cases was 3.79±0.78 and for controls 1.99±0.28. There was significant correlation between HbA1c by Ion Exchange Resin Method and fructosamine by NBT Reduction Method. The correlation coefficient r for case was 0.633 and for controls r = 0.643 (p< 0.05). NBT Reduction method for fructosaminehas been standardized and linear graph was obtained. HbA1c and fructosamine showed significant correlation with FBS, PPBS values and duration of diabetes. Calculated HbA1c from fructosamine result show significant correlation with HbA1c by Ion Exchange Resin method. Conclusion: The significant correlation of fructosamine with HbA1c suggests that, fructosamine can be used as an early marker of glycemic control than HbA1c as the half life of serum albumin is only 14 – 21 days. NBT Reduction method is rapid, inexpensive and time saving technique can be used as a routine test.