Clinical Utility of Assays of Glycosylated Haemoglobin and Serum Fructosamine Compared: Use of Data on Biological Variation

Abstract

Assessment of the relative clinical usefulness of glycosylated haemoglobin (HbA1) and serum fructosamine is complicated by their markedly different half-lives. They have therefore been compared using a number of indices derived from data on biological variation, as applied in a study of blood glucose control in newly diagnosed diabetic patients. The within-subject (CVI) and between-subject (CVG) variation of fructosamine and HbA1 were assessed in 8 stable diabetic patients. A slightly smaller relative change, or critical difference, is required between serial HbA1 results than between fructosamine results before a significant change can be said to have occurred. The heterogeneity of within-subject variance is also less for HbA1, rendering the critical difference more generally applicable. HbA1 may therefore be more appropriate for long-term monitoring. Monitoring of blood glucose control of a group of 26 newly diagnosed diabetic patients before the commencement of therapy and 1, 2, and 3 months later by serum fructosamine or HbA1 provided very similar information. Fructosamine responds more rapidly with changes of blood glucose control. However, whether this confers any clinical advantage will depend upon the frequency of testing.

Issues to consider when attempting to achieve the American Diabetes Association clinical quality requirement for haemoglobin A1c

“…Clinicians see the effects of total variation when treating patients, so the pathological variation must be included in the calculation of the quality requirement. This is in keeping with Fraser as 'there are some data derived from groups with specific disease in the literature' 19 , including diabetes [20][21][22][23][24] .…”

“…Combining a manufacturer's CV A of 2.14% 28 and CV I of 5.1%, results in a CV T of 5.5%. This is likely to be an underestimate as the listed CV A is often less than that found in routine practice 12 and higher CV I s have been reported [20][21][22]24 . Using the total error concept, this implies: TE < Bias + (1.65 × Total variation) (CV at any set point) 1% < Bias + (1.65 × 0.055 × 7.0)% (when using the general ADA A1C target of 7.0% Bias < 1 -0.64%, i.e.…”

“…However, lower values of A1C will produce higher CVs for a common variance (20). While CV B seems to be < 1% in euglycaemic individuals 18 , the intra-individual CV (CV I ) in patients with diabetes is 4.1-9.8% [20][21][22][23][24] . Therefore the CV I is larger than the analytical CV (CV A ).…”

Testes sanguíneos de biomarcadores para diagnóstico e tratamento de desordens mentais: foco em esquizofrenia

“…Her2 expression in breast cancer 43 Human chorionic gonadotropin protein and pregnancy 44 Triple Test/Quad Test in Down's syndrome 45 Estriol, b-HCG, alfa-fetoprotein Estriol, b-HCG, alfa-fetoprotein, inhibin Health OncoDx test for breast cancer 46 21 genes for prediction of best treatment Glycosylated haemoglobin and serum fructosamine in type II diabetes 47 One problem that we have faced in the development of this test relates to the fact that the targeted patient populations were selected and classified on the basis of DSM-IV criteria which is sometimes questionable, as discussed above. Therefore, our initial studies involved systematic selection of patients with regards to psychopathology and disease stage with a focus on paranoid schizophrenia patients who were mostly in the first episode of illness and drug naive.…”

The Association of Glycemic Markers with Plasma Adipocytokine Levels in Women with Gestational Diabetes

“…Therefore, the improvement or deteriation of blood glucose level in short period are not reflected exactly with HbA1C. However, fructosamine levels indicate all glycated proteins including albumin, lipoprotein and globulin and has been reported to show larger intra-individual variability compared with HbA1C [27]. Serum protein concentrations and dilutional anemia which may develop during pregnancy can affect fructosamine levels [28].…”