Abstract:

Objective    To evaluate effects of five screening methods for asymptomatic type 2 diabetes, i.e. fasting capillary blood glucose (FCBG), fasting plasma glucose (FPG),  2hour plasma glucose (2HPG), glycosylated haemoglobin (HbA1c) and Diabetes Risk Score (DRS) by establishing receiver operating characteristic (ROC) curve models.  Methods    Data from a cross-sectional survey of 4070 subjects who underwent the oral glucose tolerance tests (OGTT) for type 2 diabetes screening in the Qingdao Diabetes Prevention Program in 2006 were analyzed. All the subjects had no history of diabetes and were required to test FCBG， FPG， 2HPG， HbA1c and finished the DRS designed for the program at the same time. The sensitivity, specificity, and the area under the ROC curve (AUROC) of the five methods for detecting asymptomatic diabetes were calculated to evaluate their effects.  Results    The sensitivity, specificity and  AUROC of the five methods were as follows:① FCBG： 64.08%， 69.81% and 0.712; ② FPG:60.10%，100.00% and 0.896； ③ 2HPG: 67.12%，100.00% and 0.898； ④ HbA1c: 40.21%， 81.96% and 0.673； and  ⑤ DRS: 61.50%， 63.72 and 0.679.  FPG and 2HPG had significant differences in AUROC from the other three screening methods (P＜0.001).  The difference of AUROC between FPG and 2HPG and the differences of AUROC between FCBG, HbA1c and DRS were not significant (P＞0.05).  Conclusion    FCBG and DRS may be simple and effective methods in primary detection for symptomless diabetics. HbA1c is not suitable for screening T2DM at present in the community until conditions permit. If the diagnosis thresholds of FPG and 2HPG are properly lowered, their diagnostic sensitivity will be enhanced and the rate of missed diagnosis reduced.

Key words: Type 2 diabetes mellitus; Screening; Fasting capillary blood glucose; Fasting plasma glucose； 2-hour plasma glucose； Glycosylated haemoglobin； Diabetes risk score; Receiver operating characteristic