Alternative biomarkers for assessing glycemic control in diabetes: fructosamine, glycated albumin, and 1,5-anhydroglucitol

Article information

Ann Pediatr Endocrinol Metab. 2015;20(2):74-78
Publication date (electronic) : 2015 June 30
doi : https://doi.org/10.6065/apem.2015.20.2.74
Department of Pediatrics, Inha University Hospital, Inha University Graduate School of Medicine, Incheon, Korea.
Address for correspondence: Ji-Eun Lee, MD, PhD. Department of Pediatrics, Inha University Hospital, Inha University Graduate School of medicine, 27 Inhang-ro, Jung-gu, Incheon 400-711, Korea. Tel: +82-32-890-3617, Fax: +82-32-890-3099, anicca@inha.ac.kr
Received 2015 June 26; Accepted 2015 June 26.

Abstract

The growing attention to alternative glycemic biomarkers including fructosamine, glycated albumin (GA), 1,5-anhydroglucitol (1,5-AG), is attributable to the limitations of the glycated hemoglobin (HbA1c) assay. It is important to recognize the conditions in which HbA1c levels may be difficult to interpret. Serum fructosamine and GA have been proposed useful tools for monitoring of short-term glycemic control. These biomarkers not only reflect well glycemic control in hematologic disorder, but also represent postprandial glucose fluctuation. Serum 1,5-AG may be useful for estimating within-day glucose variation. Use of these nontraditional tests can be more helpful in the management of diabetes as complement traditional measures. Further larger cohort studies are warranted to determine whether nontraditional biomarkers have potential utility for early diagnosis, management of diabetes, and prevention of diabetic complications.

Introduction

Diabetes mellitus (DM) is a chronic metabolic syndrome exhibiting hyperglycemia. Strict glycemic control is essential for preventing the complications of diabetes. Serum glycemic biomarkers have been effective measures used to monitor glycemic control in clinical practice1). Traditionally, glycated hemoglobin (HbA1c) has been used as the standard measure for long-term glucose control. In addition, the role of HbA1c was further broadened as the guidelines from the American Diabetes Association2) and the World Health Organization3) introduced HbA1c for the diagnosis of DM in 2009.

There has been increasing interest in nontraditional glycemic markers as alternatives to HbA1c45). Because of the situations that can be reduced the validity of HbA1c test, it is important to interpret HbA1c values in various conditions. This article will review the limitations of HbA1c measurement and the current knowledge about alternative glycemic biomarkers, including fructosamine, glycated albumin (GA), and 1,5-anhydroglucitol (1,5-AG).

Limitations of HbA1c

HbA1c are influenced by red blood cells (RBC) survival. Because the average lifespan of RBC is 120 days, HbA1c reflects mean glucose levels over the preceding two to three months. Falsely elevated HbA1c in relation to a mean blood glucose concentrations can be achieved when RBC turnover is decreased, resulting in a disproportionate number of older RBC. This problem can occur in patients with iron, vitamin B12, or folate deficiency anemia. Inversely, increased RBC turnover leads to a greater proportion of younger RBC and falsely lowed HbA1c values, such as in conditions with acute and chronic blood loss, hemolysis or pregnancy, anemia and patients treated for iron, vitamin B12, or folate deficiency, and treated with erythropoietin678). HbA1c values may be falsely high or low in those with end-stage renal disease9).

HbA1c cannot be used as a glycemic marker in neonatal DM. During the perinatal period, fetal hemoglobin (HbF) is the main component of hemoglobin and less than 10% is hemoglobin A. HbA1c values typically are low in relation to hyperglycemia in neonatal diabetes. HbA1c is influenced by changes according to age in HbF, and does not precisely reflect glycemic control in neonate1011).

In addition, HbA1c levels are no accurate in reflecting shortterm glycemic changes. While glycemic control changes rapidly, HbA1c changes gradually. As a result, measuring HbA1c to evaluate responses to glucose-lowering treatment in DM patients may be useful after twelve weeks12). In patients with fulminant type 1 DM (in which hyperglycemia rapidly occurs), HbA1c may not be a reliable indicator due to its normal or only slightly elevated levels13).

Mean HbA1c values are associated with the development and progression of diabetic complications141516). Several studies have noted the relationship between postprandial hyperglycemia and cardiovascular disease15). Better control of glycemic variability is one of the most important ways to prevent cardiovascular disease in diabetes. HbA1c is a measure that mainly reflects average serum glucose concentration, but it does not separately reflect postprandial hyperglycemia and fasting hyperglycemia1516).

Alternative biomarkers

There are several alternative biomarkers to HbA1c in use today, including fructosamine, GA, 1,5-AG, and continuous glucose monitoring, described below.

1. Fructosamine

Fructosamine is a ketoamine formed from the binding of fructose to total serum protein, mostly albumin, through glycosylation17). The term fructosamine includes all glycated proteins. Fructosamine assays are cheaper and easier to perform than HbA1c assays. Serum fructosamine values reflect mean blood glucose concentrations over the previous two to three weeks, which can be used clinically as markers of recent changes in glycemic control. When used in combination with other measures, it may play a role in identifying fluctuating glucose levels in DM patients with stable HbA1c. There is a good correlation between HbA1c values and serum fructosamine1819).

There are also several limitations to the use of serum fructosamine measurements. The higher within-subject variation for fructosamine than that for HbA1c means that frequent measurements must be conducted20). Serum fructosamine values must be adjusted if the serum albumin concentration is abnormal21). Falsely low levels in relation to mean blood glucose levels will occur with rapid albumin turnover, such as in nephrotic syndrome, severe liver disease, or protein-losing enteropathy. The level of fructosamine in young children is lower than that in adults, which is also partly due to their lower serum protein concentration22).

2. Glycated albumin

GA is the proportion of the serum GA to the total albumin. GA is similar to serum fructosamine, except that is not affected by serum albumin levels23). The level of GA is approximately three times higher than that of HbA1c. Since the half-life of albumin is shorter than that of RBC, GA reflects a shorter duration, two to three weeks, of glycemic control, than that of HbA1c24). GA and fructosamine are strongly associated with HbA1c and fasting glucose252627).

1) Clinical usefulness of GA

GA has several advantages for monitoring for glucose control. The first is that it is not influenced by abnormal RBC lifespan or variant hemoglobin. GA is a particularly useful indicator of glycemic control in hematologic disorders, such as in anemia, hemorrhage, renal anemia, pregnancy, liver cirrhosis, and neonatal DM. The second advantage is that GA may be quite useful for conditions in which glycemia improves rapidly, or in which glycemia deteriorates rapidly, such as in fulminant type I DM. GA will provide a more accurate assessment of recent glycemia. Finally, when compared with HbA1c values, GA values have more correlation with postprandial glucose levels and glucose excursions2829). Because the glycation speed of GA is ten times faster than HbA1c, GA is likely to reflect variations in blood glucose and postprandial hyperglycemia in combination with HbA1c and its value30). It has been reported that GA is related to daily glucose fluctuation20).

2) Limitations of GA

GA has abnormal values in diseases that result in abnormal albumin metabolism. The rise of albumin metabolism leads to low GA levels in diseases including nephrotic syndrome, hyperthyroidism, glucocorticoid administration, Cushing's syndrome, and in neonates10313233). Whereas albumin metabolism decreases, high GA levels are seen in diseases such as liver cirrhosis and hypothyroidism34).

Unlike HbA1c, GA is inversely influenced by obesity. GA tends to be lower in obese subjects with a high percentage of body fat mass35). In addition, GA levels in infants significantly increase with age36). The serum glucose levels of infants are lower than that of adults, and higher albumin metabolism is associated with lower GA levels.

3. 1,5-anhydroglucitol

The 1-deoxy form of glucose known as 1,5-AG is a naturally occurring dietary polyol. During euglycemia, serum 1,5-AG concentrations are maintained at a constant steady state due to renal tubular reabsorption of all of the serum 1,5-AG. The normal serum concentration of 1,5-AG has been reported to be 12-40 µg/mL37). Serum 1,5-AG competes with very high levels of glucose for reabsorption into the kidney. Within 24 hours of a rise in serum glucose to >180 mg/dL, serum circulating 1,5-AG falls as urinary losses increase3839). Lower serum 1,5-AG levels reflect high circulating glucose and the occurrence of glycosuria over the past 1 to 2 weeks4041). Measurement of serum 1,5-AG may reflect postprandial glycemic excursion rather than HbA1c424344). While 1,5-AG may have clinical implications for the evaluation and treatment of glycemic excursions in type 1 diabetes45), this test is affected by alteration in renal hemodynamics.

4. Continuous glucose monitoring

Although the use of continuous glucose monitoring can accurately evaluate the glycemic variability of within-day and between-day, the current continuous glucose monitoring systems are expensive without national health insurance coverage and are not easily available in clinical practice. Furthermore, they are relatively inaccurate in the lower glucose range, and should be used in conjunction with self-monitoring of blood glucose46).

Conclusions

The growing attention to nontraditional glycemic biomarkers is attributable to the limitations of the HbA1c assay474849). It is important to recognize the conditions in which HbA1c levels may be difficult to interpret. Use of these alternative markers can be more helpful in the management of diabetes as complement standard measures. There are generally good correlations of HbA1c with serum fructosamine and GA. Fructosamine and GA have been proposed to be useful tools for monitoring short-term glycemic control. These biomarkers not only reflect well glycemic control in hematologic disorder, but also represent postprandial glucose fluctuation. Serum 1,5-AG may be useful for estimating within-day glycemic excursion. Nevertheless, there are no definitive guidelines for using alternative biomarkers as adjuncts to standard markers of glycemia, such as HbA1c, fasting glucose, or self-monitoring blood glucose measures49). Long-term prospective studies are still lacking. Further larger cohort studies are warranted to determine whether alternative biomarkers have potential utility for early diagnosis, management of diabetes, and prevention of diabetic complications.

Notes

Conflict of interest: No potential conflict of interest relevant to this article was reported.

References

1. Goldstein DE, Little RR, Lorenz RA, Malone JI, Nathan D, Peterson CM. Tests of glycemia in diabetes. Diabetes Care 1995;18:896–909. 7555528.
2. International Expert Committee. International Expert Committee report on the role of the A1C assay in the diagnosis of diabetes. Diabetes Care 2009;32:1327–1334. 19502545.
3. Use of glycated haemoglobin (HbA1c) in the diagnosis of diabetes mellitus: abbreviated report of a WHO Consultation Geneva: World Health Organization; 2011.
4. Radin MS. Pitfalls in hemoglobin A1c measurement: when results may be misleading. J Gen Intern Med 2014;29:388–394. 24002631.
5. Parrinello CM, Selvin E. Beyond HbA1c and glucose: the role of nontraditional glycemic markers in diabetes diagnosis, prognosis, and management. Curr Diab Rep 2014;14:548. 25249070.
6. National Glycohemoglobin Standardization Program (NGSP). Factors that Interfere with HbA1c test results [Internet] NGSP; c2011. cited 2015 May 20. Available from: http://www.ngsp.org/factors.asp.
7. Polgreen PM, Putz D, Stapleton JT. Inaccurate glycosylated hemoglobin A1C measurements in human immunodeficiency virus-positive patients with diabetes mellitus. Clin Infect Dis 2003;37:e53–e56. 12905153.
8. Brown JN, Kemp DW, Brice KR. Class effect of erythropoietin therapy on hemoglobin A(1c) in a patient with diabetes mellitus and chronic kidney disease not undergoing hemodialysis. Pharmacotherapy 2009;29:468–472. 19323622.
9. Ly J, Marticorena R, Donnelly S. Red blood cell survival in chronic renal failure. Am J Kidney Dis 2004;44:715–719. 15384023.
10. Suzuki S, Koga M, Niizeki N, Furuya A, Matsuo K, Tanahashi Y, et al. Evaluation of glycated hemoglobin and fetal hemoglobin-adjusted HbA1c measurements in infants. Pediatr Diabetes 2013;14:267–272. 23350671.
11. Suzuki S, Koga M, Amamiya S, Nakao A, Wada K, Okuhara K, et al. Glycated albumin but not HbA1c reflects glycaemic control in patients with neonatal diabetes mellitus. Diabetologia 2011;54:2247–2253. 21644010.
12. Koga M, Murai J, Saito H, Kasayama S. Prediction of near-future glycated hemoglobin levels using glycated albumin levels before and after treatment for diabetes. J Diabetes Investig 2011;2:304–309.
13. Imagawa A, Hanafusa T, Miyagawa J, Matsuzawa Y. Osaka IDDM Study Group. A novel subtype of type 1 diabetes mellitus characterized by a rapid onset and an absence of diabetes-related antibodies. N Engl J Med 2000;342:301–307. 10655528.
14. The Diabetes Control and Complications Trial Research Group. The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus. N Engl J Med 1993;329:977–986. 8366922.
15. Wang PH, Lau J, Chalmers TC. Meta-analysis of effects of intensive blood-glucose control on late complications of type I diabetes. Lancet 1993;341:1306–1309. 8098449.
16. Reichard P, Nilsson BY, Rosenqvist U. The effect of long-term intensified insulin treatment on the development of microvascular complications of diabetes mellitus. N Engl J Med 1993;329:304–309. 8147960.
17. Mosca A, Carenini A, Zoppi F, Carpinelli A, Banfi G, Ceriotti F, et al. Plasma protein glycation as measured by fructosamine assay. Clin Chem 1987;33:1141–1146. 3594841.
18. Pandya HC, Livingstone S, Colgan ME, Percy-Robb IW, Frier BM. Serum fructosamine as an index of glycaemia: comparison with glycated haemoglobin in diabetic and non-diabetic individuals. Pract Diabetes Int 1987;4:126–128.
19. Narbonne H, Renacco E, Pradel V, Portugal H, Vialettes B. Can fructosamine be a surrogate for HbA(1c) in evaluating the achievement of therapeutic goals in diabetes? Diabetes Metab 2001;27(5 Pt 1):598–603. 11694860.
20. Matsumoto H, Murase-Mishiba Y, Yamamoto N, Sugitatsu-Nakatsukasa S, Shibasaki S, Sano H, et al. Glycated albumin to glycated hemoglobin ratio is a sensitive indicator of blood glucose variability in patients with fulminant type 1 diabetes. Intern Med 2012;51:1315–1321. 22687835.
21. Howey JE, Browning MC, Fraser CG. Assay of serum fructosamine that minimizes standardization and matrix problems: use to assess components of biological variation. Clin Chem 1987;33(2 Pt 1):269–272. 3802511.
22. Miyazaki A, Kohzuma T, Kasayama S, Koga M. Classification of variant forms of haemoglobin according to the ratio of glycated haemoglobin to glycated albumin. Ann Clin Biochem 2012;49(Pt 5):441–444. 22715294.
23. Kim D, Kim KJ, Huh JH, Lee BW, Kang ES, Cha BS, et al. The ratio of glycated albumin to glycated haemoglobin correlates with insulin secretory function. Clin Endocrinol (Oxf) 2012;77:679–683. 22150917.
24. Koga M, Hashimoto K, Murai J, Saito H, Mukai M, Ikegame K, et al. Usefulness of glycated albumin as an indicator of glycemic control status in patients with hemolytic anemia. Clin Chim Acta 2011;412:253–257. 20965159.
25. Juraschek SP, Steffes MW, Selvin E. Associations of alternative markers of glycemia with hemoglobin A(1c) and fasting glucose. Clin Chem 2012;58:1648–1655. 23019309.
26. Lee JW, Kim HJ, Kwon YS, Jun YH, Kim SK, Choi JW, et al. Serum glycated albumin as a new glycemic marker in pediatric diabetes. Ann Pediatr Endocrinol Metab 2013;18:208–213. 24904879.
27. Shin YS, Park J, Kang DS, Yu J. Significance of the measurement of serum fructosamine in the management of childhood diabetes. Int J Pediatr Endocrinol 2013;2013(Suppl 1):P36.
28. Koga M, Murai J, Morita S, Saito H, Kasayama S. Comparison of annual variability in HbA1c and glycated albumin in patients with type 1 vs. type 2 diabetes mellitus. J Diabetes Complications 2013;27:211–213. 23312788.
29. Hirsch IB, Brownlee M. Beyond hemoglobin A1c--need for additional markers of risk for diabetic microvascular complications. JAMA 2010;303:2291–2292. 20530784.
30. Chon S, Lee YJ, Fraterrigo G, Pozzilli P, Choi MC, Kwon MK, et al. Evaluation of glycemic variability in well-controlled type 2 diabetes mellitus. Diabetes Technol Ther 2013;15:455–460. 23617251.
31. Koga M, Murai J, Saito H, Otsuki M, Kasayama S. Evaluation of the glycated albumin/HbA1c ratio by stage of diabetic nephropathy. Diabetol Int 2011;2:141–145.
32. Koga M, Murai J, Saito H, Matsumoto S, Kasayama S. Effects of thyroid hormone on serum glycated albumin levels: study on non-diabetic subjects. Diabetes Res Clin Pract 2009;84:163–167. 19243849.
33. Suzuki S, Koga M, Takahashi H, Matsuo K, Tanahashi Y, Azuma H. Glycated albumin in patients with neonatal diabetes mellitus is apparently low in relation to glycemia compared with that in patients with type 1 diabetes mellitus. Horm Res Paediatr 2012;77:273–276. 22538993.
34. Koga M. Glycated albumin: clinical usefulness. Clin Chim Acta 2014;433:96–104. 24631132.
35. Koga M, Matsumoto S, Saito H, Kasayama S. Body mass index negatively influences glycated albumin, but not glycated hemoglobin, in diabetic patients. Endocr J 2006;53:387–391. 16717395.
36. Suzuki S, Koga M, Niizeki N, Furuya A, Takahashi H, Matsuo K, et al. Glycated albumin is lower in infants than in adults and correlated with both age and serum albumin. Pediatr Diabetes 2013;14:25–30. 22816963.
37. Yamanouchi T, Akanuma Y. Serum 1,5-anhydroglucitol (1,5 AG): new clinical marker for glycemic control. Diabetes Res Clin Pract 1994;24(Suppl):S261–S268. 7859616.
38. Buse JB, Freeman JL, Edelman SV, Jovanovic L, McGill JB. Serum 1,5-anhydroglucitol (GlycoMark ): a short-term glycemic marker. Diabetes Technol Ther 2003;5:355–363. 12828817.
39. Dungan KM. 1,5-anhydroglucitol (GlycoMark) as a marker of short-term glycemic control and glycemic excursions. Expert Rev Mol Diagn 2008;8:9–19. 18088226.
40. Yamanouchi T, Minoda S, Yabuuchi M, Akanuma Y, Akanuma H, Miyashita H, et al. Plasma 1,5-anhydro-D-glucitol as new clinical marker of glycemic control in NIDDM patients. Diabetes 1989;38:723–729. 2656341.
41. Stettler C, Stahl M, Allemann S, Diem P, Schmidlin K, Zwahlen M, et al. Association of 1,5-anhydroglucitol and 2-h postprandial blood glucose in type 2 diabetic patients. Diabetes Care 2008;31:1534–1535. 18426859.
42. Kishimoto M, Yamasaki Y, Kubota M, Arai K, Morishima T, Kawamori R, et al. 1,5-Anhydro-D-glucitol evaluates daily glycemic excursions in well-controlled NIDDM. Diabetes Care 1995;18:1156–1159. 7587851.
43. McGill JB, Cole TG, Nowatzke W, Houghton S, Ammirati EB, Gautille T, et al. Circulating 1,5-anhydroglucitol levels in adult patients with diabetes reflect longitudinal changes of glycemia: a U.S. trial of the GlycoMark assay. Diabetes Care 2004;27:1859–1865. 15277408.
44. Dungan KM, Buse JB, Largay J, Kelly MM, Button EA, Kato S, et al. 1,5-anhydroglucitol and postprandial hyperglycemia as measured by continuous glucose monitoring system in moderately controlled patients with diabetes. Diabetes Care 2006;29:1214–1219. 16731998.
45. Seok H, Huh JH, Kim HM, Lee BW, Kang ES, Lee HC, et al. 1,5-anhydroglucitol as a useful marker for assessing short-term glycemic excursions in type 1 diabetes. Diabetes Metab J 2015;39:164–170. 25922811.
46. Chiang JL, Kirkman MS, Laffel LM, Peters AL. Type 1 Diabetes Sourcebook Authors. Type 1 diabetes through the life span: a position statement of the American Diabetes Association. Diabetes Care 2014;37:2034–2054. 24935775.
47. Juraschek SP, Steffes MW, Miller ER 3rd, Selvin E. Alternative markers of hyperglycemia and risk of diabetes. Diabetes Care 2012;35:2265–2270. 22875225.
48. Rondeau P, Bourdon E. The glycation of albumin: structural and functional impacts. Biochimie 2011;93:645–658. 21167901.
49. Goldstein DE, Little RR, Lorenz RA, Malone JI, Nathan D, Peterson CM, et al. Tests of glycemia in diabetes. Diabetes Care 2004;27:1761–1773. 15220264.

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