CC BY-NC-ND 4.0 · J Lab Physicians 2023; 15(02): 217-223
DOI: 10.1055/s-0042-1757719
Original Article

Correlation between Estimated Average Glucose Levels Calculated from HbA1c Values and Random Blood Glucose Levels in a Cohort of Subjects

Pinky Garg
1   Department of Biochemistry, North DMC Medical College and Hindu Rao Hospital, Delhi, India
,
2   Department of Biochemistry, All India Institute of Medical Sciences, Delhi, India
,
Rajiv Ranjan
1   Department of Biochemistry, North DMC Medical College and Hindu Rao Hospital, Delhi, India
› Author Affiliations
Funding None.

Abstract

Objective Hemoglobin A1c (HbA1c) level remains the gold standard test for the assessment of glycemic control, and it reflects the mean glucose values in the previous 3-month period. HbA1c is expressed as a percentage, whereas the monitoring and treatment of diabetes are based on blood glucose levels expressed as mg/dL. It is appropriate to make it easy for the patient to understand both random blood sugar (RBS) and estimated average glucose (eAG) expressed with the same units. This will enhance the usefulness of eAG. This article determines the statistical correlation between eAG derived from HBA1C with RBS values both in diabetic and prediabetic subjects.

Methods The RBS and HbA1c levels of 178 males and 283 females (12–90 years) were obtained and the eAG levels were calculated using Nathan's regression equation. The samples were divided into four groups based on HbA1c levels—group 1: HbA1c greater than 9%, group 2: HbA1c 6.5 to 9%, group 3: HbA1c 5.7 to 6.4%; and group 4: HbA1c less than 5.7%.

Results There was a statistically significant positive correlation between RBS and eAG values for the study group 1 and 2. Also, the median values of RBS and eAG showed a significant difference (p < 0.001).

Conclusion As the association between the RBS and eAG levels is strong in a fairly and poorly controlled diabetic population, reporting the eAG level together with the HbA1c level at no additional cost may assist in effective blood glucose control in clinical care. However, eAG and RBS values cannot be used interchangeably.



Publication History

Article published online:
20 October 2022

© 2022. The Indian Association of Laboratory Physicians. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India

 
  • References

  • 1 International Diabetes Federation. IDF Diabetes Atlas. 9th ed.. Brussels, Belgium: International Diabetes Federation; 2019
  • 2 Deepa M, Grace M, Binukumar B. et al; CARRS Surveillance Research Group. High burden of prediabetes and diabetes in three large cities in South Asia: the Center for cArdio-metabolic Risk Reduction in South Asia (CARRS) study. Diabetes Res Clin Pract 2015; 110 (02) 172-182
  • 3 Gupta S, Jain U, Chauhan N. Laboratory diagnosis of HbA1c: a review. J Nanomed Res 2017; 5: 00120
  • 4 UK Prospective Diabetes Study (UKPDS) Group. Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet 1998; 352 (9131): 837-853
  • 5 American Diabetes Association. Standards of medical care in diabetes–2010. Diabetes Care 2010; 33 (Suppl. 01) S11-S61
  • 6 Wang D, Chen Y. Usefulness of estimated average glucose (eAG) in glycemic control and cardiovascular risk reduction. Clin Biochem 2020; 84: 45-50
  • 7 Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ. A1c-Derived Average Glucose Study Group. Translating the A1C assay into estimated average glucose values. Diabetes Care 2008; 31 (08) 1473-1478
  • 8 Chawla R, Madhu SV, Makkar BM, Ghosh S, Saboo B, Kalra S. RSSDI-ESI Consensus Group. RSSDI-ESI clinical practice recommendations for the management of type 2 diabetes mellitus 2020. Indian J Endocrinol Metab 2020; 24 (01) 1-122
  • 9 Kariyawasan CC. The association between Hba1c-derived estimated average glucose (eAG) with fasting blood sugar (FBS) and post prandial blood sugar (PPBS) in patients with type 2 diabetes in a cohort of patients in a tertiary care hospital in Sri Lanka. Clinics (São Paulo) 2021; 3 (02) x
  • 10 Bozkaya G, Ozgu E, Karaca B. The association between estimated average glucose levels and fasting plasma glucose levels. Clinics (São Paulo) 2010; 65 (11) 1077-1080
  • 11 Law GR, Gilthorpe MS, Secher AL. et al. Translating HbA1c measurements into estimated average glucose values in pregnant women with diabetes. Diabetologia 2017; 60 (04) 618-624
  • 12 Young IS. Counterpoint: The reporting of estimated glucose with hemoglobin A1c. Clin Chem 2010; 56 (04) 547-549
  • 13 Rosediani M, Azidah AK, Mafauzy M. Correlation between fasting plasma glucose, post prandial glucose and glycated haemoglobin and fructosamine. Med J Malaysia 2006; 61 (01) 67-71
  • 14 Mahato RV, Nepal AK, Gelal B. et al. Association of estimated average glucose (eAG) with fasting, postprandial and average of fasting and PP serum glucose levels. Journal of Nepal Association for Medical Laboratory Sciences. 2012; 11 (01) 14-18
  • 15 Kim HY, Lee SY, Suh S, Kim JH, Lee MK, Park HD. The relationship between estimated average glucose and fasting plasma glucose. Clin Chem Lab Med 2013; 51 (11) 2195-2200
  • 16 Guan X, Zheng L, Sun G. et al. The changing relationship between HbA1c and FPG according to different FPG ranges. J Endocrinol Invest 2016; 39 (05) 523-528
  • 17 Azim W, Omair M, Khan MQA, Shaheen N, Azim S. Correlation between glycated haemoglobin and random plasma glucose levels for the screening of diabetes mellitus. Int J Pathol 2010; 8 (02) 59-62
  • 18 Ram N, Ahmed S, Sattar S, Furqan S, Islam N. Relationship between estimated average glucose (eAG) and fasting plasma glucose in a cohort of Pakistani diabetic subjects. Cureus 2021; 13 (10) e18435
  • 19 Nkoana MK, Khine AA. Correlation between self-monitored mean blood glucose and average plasma glucose estimated from glycated haemoglobin in patients attending the diabetes clinic at Dr George Mukhari Academic Hospital, Pretoria, South Africa. S Afr Med J 2020; 110 (05) 416-421