Poor performance of HbA1C in diagnosis of pre-diabetes in Chinese adolescents / 中华内分泌代谢杂志

ABSTRACT

Objective To evaluate the performance of HbA1C in diagnosis of pre-diabetes in Chinese adolescents.Methods A total of 933 students(aged 13-16 year,46.5% female)without known history of diabetes were selected from junior and senior middle schools in Liaoyang city.HbA1C and fasting plasma glucose(FPG)levels were determined in all participants.Pre-diabetes was diagnosed as according to 2010 American Diabetes Association (ADA)criteria[HbA1C 5.7%-6.4%,FPG(5.6-6.9)mmol/L].The individuals with HbA1C ≥5.7% underwent oral glucose tolerance test(OGTT)and were classified into impaired glucose tolerance(IGT)and impaired fasting glucose(IFG)according to 1999 World Health Organization(WHO)criteria.The performance of HbA1C in diagnosing pre-diabetes by the new criteria was evaluated by the traditional OGTT results based on receiver operating characteristic(ROC)curves.Results Among all participants,213(22.8%)individuals were diagnosed as prediabetic subjects.72.3% of individuals with pre-diabetes were identified by HbA1C alone,23.0% by FPG alone,and only 4.7% by both tests simultaneously.The ROC curve for HbA1C to identify impaired fasting glucose diagnosed by new criteria had an area under the curve(AUC)of 0.50 without statistical significance(P = 0.97).Of the 164 participants with HbA1C 5.7% -6.4%,68 individuals received OGTT,among which 18 subjects were diagnosed as IGT(n= 14)or IFG(n = 4).The ROC curve for HbA1C to identify pre-diabetes diagnosed by OGTT had an AUC of 0.53,without statistical significance(P = 0.69).Conclusion In Chinese adolescents,HbA1C is not suitable for diagnosis or screening of pre-diabetes.