The value of HbA1c for diagnosing type 2 diabetes mellitus between Chinese Uyghurs and Hans in Xinjiang.

OBJECTIVE To compare the difference of glycosylated hemoglobin (HbA1c) for diagnosing type 2 diabetes mellitus (T2DM) between Chinese Uyghurs and Hans in xinjiang. METHODS we collected 707 subjects, including 456 Uyghurs and 251 Hans in Xinjiang Kashi region. All the subjects were underwent oral glucose tolerance test (OGTT) for diagnosing T2DM, at the same time their clinical biochemical markers and HbA1c levels were also measured. Then the data were analyzed, the receiver operating characteristic (ROC) curve was plotted and correlation analysis were made by SPSS 19.0 software. RESULTS 1. The levels of body mess index (BMI), 2-hour plasma glucose (2 h PG), diastolic blood pressure (DBP) total cholestero (TC) and triglycerides (TG) were 26.6±4.75 kg/m(2), 14.3±6.2 mmol/l, 81.6±13.4 mmHg, 4.5±1.3 mmol/l and 4.3±2.8 mmol/l in Uyghurs, moreover those were higher than Hans [25.4±13.3 kg/m(2), 13.1±6.9 mmol/l, 78.4±9.9 mmHg, 2.3±2.1 mmol/l and 2.0±1.4 mmol/l, (P<0.05)]. 2. Otherwise, the optimal cut-off value for HbA1c to diagnose T2DM was 6.95% in Uyghurs. At this cut-off value, the sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (-LR) and the area under the ROC curve (AUC) were 98.3%, 97.7%, 43.64, 0.017 and 0.997. While the optimal cut-off value was 7.05% in Hans, and, the sensitivity, specificity, +LR, -LR and AUC separately were 91.1%, 92.8%, 0.971, 12.6, 0.096 and 0.971. 3. The correlation analysis was made in two populations. It demonstrated that HbA1c was positively correlated with BMI, TC and TG in Uyghurs (r=0.138, 0.273, 0.482, P<0.05). However, in Hans, the HbA1c only was positively correlated with TG (r=0.178, P<0.05). CONCLUSION The Uyghurs have higher metabolic markers, for example, BMI, TC, DBP and TG. It reveals that Uyghurs may have more severe insulin resistance (IR) comparing with Hans. And then, the cut-off value of HbA1c for diagnosing and screening T2DM is different between Uyghurs and Hans in Xinjiang.