Correlation of glycosylated hemoglobin and blood glucose levels of impaired glucose regulation

Abstract

Objective To investigate the correlation of glycosylated hemoglobin (HbA1c) and impaired glucose regulation(IGR). Methods Seventy-five g oral glucose tolerance test(OGTT)and HbA1c levels were carried out among our hospital staffs. The subjects were determined fasting plasma glucose(FPG), oral glucose 2 h plasma glucose(2 h PG)and HbA1c, plasma glucose levels and HbA1c levels were determined by glucose oxidase method and high performance liquid chromatogram(HPLC). The inclusion criteria of subjects was FPG<7.0 mmol/L and 2 h PG<11.1 mmol/L, without diabetes, hemoglobin disease, hepatopathy and renopathy. The selected object contained 726 subjects (197 male, 529 female, mean age (39±10)), including NGT 636 subjects(87.6%), IGR 90 subjects(12.4%). The diagnostic criteria of IGR selected 1999 WHO diagnostic criteria for diabetes.χ2 test was used for rate comparison. Pearson correlation analysis was used for bivariate analysis selected. Results (1)2.3% occurred IGR among HbA1c≤5.7% subjects, while 89.3% occurred IGR among HbA1c≥5.8% subjects. When HbA1c ≥ 5.8%, the sensibility, specificity, PV+ , and PV-were 83%, 99%, 0.89, 0.98, respectively. (2)Between HbA1c level 5.8% group and HbA1c 5.7% group, the difference of prevalence of the OGTT diagnosed IFG, IGT, IGR had statistically significance(χ2 value was 10.077, 22.219 and 27.780, P<0.01 or P<0.001), (3)HbA1c levels was significant positive correlation with the prevalence of IFG, IGT, IGR(r ralue was 0.957, 0.928 and 0.936, all P<0.01). Conclusions (1)Compared with OGTT, HbA1c had consistency for predicting IGR, and the optimal critical value of HbA1c with OGTT diagnosed IGR was 5.8%.(2)HbA1c levels was significant positive correlation with the blood sugar level of the OGTT diagnosed IFG, IGT, IGR, and when HbA1c=5.8%, its relevance is most closely. The present study suggests that the HbA1c≥5.8% patients should be examined OGTT in order to identify whether the IGR. Key words: Glycosylated hemoglobin; Impaired glucose regulation; Oral glucose tolerance test