Original Research Article
Year: 2020 | Month: October-December | Volume: 5 | Issue: 4 | Pages: 65-71
Calculated Glycosylated Hemoglobin (HbA1c) Compared with Estimated HbA1c by Nephelometry and Its Correlation to Estimated Average Blood Glucose (eAG)
Shruthi Soundara Rajan1, Anitha Misquith2, Harish Rangareddy3
1II MBBS Student, Sapthagiri Institute of Medical Sciences & Research Center, Bengaluru-560090
2Assistant Professor, Department of Biochemistry, Sapthagiri Institute of Medical Sciences & Research Center, Bengaluru-560090
3Associate Professor, Department of Biochemistry, Sri Devaraj Urs Medical College, Kolar – 563101
Corresponding Author: Harish Rangareddy
ABSTRACT
Background and aim: Glycated hemoglobin is a form of hemoglobin used primarily to identify the average plasma glucose concentration over prolonged periods of time. In a developing country like India there are quite a few resource poor settings where HbA1c is not available. In such circumstances, a mathematical tool like calculated HbA1c would have some advantages over true estimation of HbA1c. This study was carried out to explore the feasibility of using such a formula to calculate HbA1c and compare with the plasma fasting and post prandial glucose levels, measured HbA1c; also to correlate with estimated average blood glucose (eAG) assessed from estimated HbA1c.
Materials and methods: This is a cross sectional study where 50 type 2 diabetes mellitus patients and 50 healthy controls were enrolled. Blood work up done for fasting plasma glucose (FBS), postprandial glucose (PPBS) and HbA1c.
Results: The mean ±SD levels of estimated HbA1c are 7.574±1.52% and calculated HbA1c 7.540± 2.29% in diabetic individuals. Estimated HbA1c is 5.629 ± 0.15% and calculated HbA1c 5.302± 0.31% in non-diabetic subjects. Though there was no difference between estimated HbA1c and calculated HbA1c by paired‘t’ test Bland Altman plot analysis with Beta coefficient showed that there was significant bias. Calculated HbA1c correlated positively with estimated average glucose (eAG) only in diabetics but not in controls.
Conclusion: The present study concludes that there is no significant difference observed in HbA1c measured by Nephelometric method and HbA1c calculated using plasma fasting glucose. However, it may not be suitable for inter changeable usage as evidenced by the bias with beta coefficient.
Keywords: HbA1c protein, Diabetes mellitus, Estimated Average Glucose