Accurate diagnosis and monitoring are crucial for managing diabetes and reducing complications. The two main tests run are those for plasma glucose and glycated hemoglobin (HbA1c). However, these are subject to a number of clinical and analytical aspects that can render them unreliable in some situations, such as in individuals suffering from kidney or red blood cell diseases. In these particular clinical scenarios, alternatives like fructosamine and glycated albumin are not only viable but also dependable, particularly in cases where glycated hemoglobin (HbA1c) is imprecise. Albumin is the primary glycated serum protein measured by fructosamine. It can be useful for monitoring and managing diabetes, especially in certain particular patient populations (Neelofar K, et al., 2019; Garrahy A., 2019; Pedrosa W, 2019).
Red blood cells' non-enzymatic hemoglobin glycation produces HbA1c, which represents the average blood glucose levels for the course of the cells' 90–120-day lifespan. Conditions impacting red blood cell turnover, however, can change glycated hemoglobin (HbA1c) readings. For example, high turnover (e.g., hemolytic anemia in patients treated for iron, vitamin B12, or folate deficiencies, as well as in patients treated with erythropoietin like in chronic kidney disease) lowers HbA1c, whereas low turnover (e.g., untreated iron deficiency anemia, folic acid, or vitamin B12 deficiencies) falsely elevates it. This uncertainty suggests that a more reliable marker is required. The synthesis of fructosamine, which happens when glucose interacts with proteins like albumin, is one such indication. In two to three weeks, it offers a replacement indication that makes blood sugar monitoring possible (Roohk HV et al., 2008). Because of its higher glycation rate, it is more effective than HbA1c for monitoring short-term glucose control (Munoz-Prieto, A., 2019; Gingras V, 2018).
Fructosamine tests can be affected by temperature variations as well as high amounts of reducing agents, such as bilirubin and vitamin C. Assays for fructosamine and glycated albumin are not standardized, and circumstances that change serum albumin levels can impact both. Since glycated albumin is represented as a percentage of total albumin, it is less affected. Serum albumin values below 3.0 g/dl make fructosamine unreliable, especially in liver cirrhosis or nephrotic syndrome. Increased protein levels in multiple myeloma (because of elevated immunoglobulins) and polyclonal gammopathies can also adversely impact fructosamine levels.
Fructosamine and glycated albumin can be used to detect prediabetes, manage diabetes, and predict issues without requiring a fasting sample. Both markers have a good connection with HbA1c and can be used as accurate, short-term indicators of glucose control. Because albumin has a naturally shorter half-life than hemoglobin in erythrocytes, fructosamine indicates glucose management over the last two to three weeks, whereas HbA1c shows glycemia over the previous eight to twelve weeks. Fructosamine and glycated albumin are safe substitutes for hemoglobin in disorders such as sickle cell anemia, iron deficiency anemia, folate and vitamin B12 deficiency anemia, and many hemoglobinopathies because they are not impacted by hemoglobin levels or problems with red blood cells, unlike HbA1c.
When modifying medication or in conditions like pregnancy where short-term glucose management is required, fructosamine is very helpful. Fructosamine and glycated albumin are both useful for tracking diabetics whose blood sugar levels are erratic or poorly controlled. In addition, they offer faster assessment of glycemic control than HbA1c, which makes them perfect for several clinical scenarios (Kohzuma T, et al, 2010). However, there are currently no guidelines that support their use for diagnosis of diabetes (Selvin E, et al., 2014).
References
Neelofar K, Ahmad J. A comparative analysis of fructosamine with other risk factors for kidney dysfunction in diabetic patients with or without chronic kidney disease. Diabetes Metab Syndr. 2019 Jan-Feb;13(1):240-244.
Garrahy A, Mijares Zamuner MB, Byrne MM. An evolving spectrum of diabetes in a woman with GCK-MODY. Endocrinol Diabetes Metab Case Rep. 2019 Jan 03;2019.
Pedrosa W, Sander Diniz MFH, Barreto SM, Vidigal PG. Establishing a blood fructosamine reference range for the Brazilian population based on data from ELSA - Brasil. Pract Lab Med. 2019 Jan;13: e00111.
Roohk HV, Zaidi AR. A review of glycated albumin as an intermediate glycation index for controlling diabetes. J Diabetes Sci Technol. 2008 Nov;2(6):1114-21.
Muñoz-Prieto A, Escribano D, Cerón JJ, Martínez-Subiela S, Tvarijonaviciute A. Glucose, fructosamine, and insulin measurements in saliva of dogs: variations after an experimental glucose administration. Domest Anim Endocrinol. 2019 Jan; 66:64-71.
Gingras V, Rifas-Shiman SL, Switkowski KM, Oken E, Hivert MF. Mid-Pregnancy Fructosamine Measurement-Predictive Value for Gestational Diabetes and Association with Postpartum Glycemic Indices. Nutrients. 2018 Dec 18;10(12).
Selvin E, Rawlings AM, Grams M, Klein R, Sharrett AR, Steffes M, Coresh J. Fructosamine and glycated albumin for risk stratification and prediction of incident diabetes and microvascular complications: a prospective cohort analysis of the Atherosclerosis Risk in Communities (ARIC) study. Lancet Diabetes Endocrinol. 2014 Apr;2(4):279-288.
Kohzuma T, Koga M. Lucica GA-L Glycated albumin assay kit: a new diagnostic test for diabetes mellitus. Mol Diagn Ther. 2010 Feb 01;14(1):49-51. Assessed and Endorsed by the MedReport Medical Review Board