Evaluation of 1, 5 -Anhydroglucitol as a Biomarker for Type 2 Diabetes Mellitus in Patients without Overt Nephropathy

1,5-Anhydroglucitol (1,5-AG) is a non-fasting glycemic marker that responds to hyperglycemia excursions. The reduction in serum levels of 1,5-AG is associated with an increase in postprandial glycemia and glycosuria, phenomena that increase the risk and severity of diabetic complications. The objective is to assess the ability of 1,5-AG to discriminate type 2 diabetes (T2D) patients without overt kidney disease, for screening or diagnostic purposes. The Human Research Ethics Committee of Universidade Federal do Paraná (UFPR) approved the project. Serum samples from 567 individuals classified as healthy subjects (n = 291) and T2D (n = 276) with moderate glycemic control (HbA1c of 7-8%), matched by gender, were analyzed. Serum 1,5-AG levels were measured using an automated enzymatic method (GlycoMark, Inc.). Receiver Operating Characteristic (ROC) curve analysis for 1,5-AG showed sensibility of 65.3% and specificity of 91.1% to detect T2D at cut-off point of 92 µmol/L. The results were similar to the groups' discrimination by glycemia (sensibility/specificity, 62.2%; 89.0%) at cut-off point of 6.3 mmol/L. HbA1c was the best discriminator (sensibility/specificity, 87.4%; 94.2%) at a cut-off point of 5.8% (40 mmol/mol). The serum 1,5-AG concentration was not able to discriminate T2D in the presence of moderate glycemic control with no overt nephropathy.

Efficiency comparison of fasting plasma glucose combined with 1,5-anhydroglucitol and combined with glycated albumin in diabetes mellitus screening / 上海交通大学学报（医学版）

Objective: To analyze and compare the clinical value of serum 1,5-anhydroglucitol (1,5-AG) with glycated albumin (GA) combined with fasting plasma glucose (FPG),respectively,in screening diabetes mellitus in Chinese population at the risk of diabetes mellitus. Methods: A total of 701 subjects with high risk of diabetes were enrolled in this study,including 324 males and 377 females. All subjects underwent 75 g oral glucose tolerance test (OGTT). Diabetes was diagnosed according to the cut-off points of 2010 American Diabetes Association standards. The sensitivity,specificity and area under ROC curve (AUC) of GA combined with FPG and 1,5-AG combined with FPG in screening diabetes mellitus were analyzed. Results: Among 701 subjects,350 (49.93%) cases were diagnosed as having diabetes mellitus. The sensitivity,specificity,and AUC of 1,5-AG combined with FPG were 84.29%,91.45% and 0.939,respectively. The sensitivity of GA combined with FPG was 77.71%,and the specificity and AUC were 90.88% and 0.932,respectively. There was no significant difference in AUC between the two screening methods (P>0.05),but the sensitivity of 1,5-AG combined with FPG was higher than that of GA combined with FPG (P=0.001). The proportion of the subjects in need of further OGTT judged by 1,5-AG combined with FPG was 27.82%,which was 11.27% lower than that judged by FPG alone,and 2.57% lower than that judged by GA combined with FPG. Conclusion: In Chinese population with high risk of diabetes mellitus,serum 1,5-AG or GA combined with FPG can improve the efficiency of diabetes screening. Compared with GA combined with FPG,1,5-AG combined with FPG may have more clinical value.

1,5-Anhydroglucitol as a Marker of Glycemic Control / 대한임상병리학회지

BACKGROUND: 1,5-Anhydroglucitol(1,5-AG) has shown to be a better indicator for current status of glycemia than HbA1c or fructosamine. The concentration of 1,5-AG is stable because of large storage pool and metabolic inertness, little influenced by assay variation with broad range of values. Since its reabsorption is competitively inhibited by glucosuria, plasma 1,5-AG decreases with increasing hyperglycemia in diabetic patients. But impairment of renal function may also affect its concentration. We introduced 1,5-AG as a new marker of glycemic control and evaluated the clinical usefulness and the effect of renal function. METHODS: We assayed plasma concentration of 1,5-AG using gas chromatography mass spectrometry in 36 healthy controls, 39 diabetic patients with normal renal function, 19 nondiabetic patients with chronic renal failure. We examined the relationship bewteen 1,5-AG and HbA1c or glucose. Correlation between 1,5-AG and serum creatinine was also investigated. RESULTS: 1,5-AG concentrations were significantly reduced in diabetic patients and in patients with chronic renal failure, compared to healthy controls. 1,5-AG had negative correlation with plasma glucose and HbA1c in healthy controls and diabetic patients with normal renal function, but not in patients with chronic renal failure. The value of 1,5-AG varies wider than that of HbA1c. CONCLUSIONS: 1,5-AG showed close correlation with glucose and HbA1c and detected subtle changes in glycemia. Therefore, measurement of 1,5-AG would be useful in monitoring glycemic control in diabetic patients with normal renal fucntion. But it would be inappropriate to use 1,5-AG for the evaluation of glycemic control in patients with renal failure.