Receiver Operating Characteristic Analysis on Fasting Plasma Glucose, HbA1c, and Fructosamine on Diabetes Screening

Abstract

Objective To determine the efficacy of HbA1c and fructosamine as alternatives to fasting plasma glucose (FPG) for diabetes screening. Research Design and Methods Receiver operating characteristic (ROC) analysis was conducted on the above tests. Comparison among tests was based on the area under ROC curve of a test. World Health Organization criteria for classifying glucose tolerance status of the subjects was used. The study consisted of subjects (n = 583) who visited the clinic from September to October 1989 and all diabetic cases (n = 36) from November 1989 to March 1990, after excluding those < 40 yr of age or with hypoglycemic therapies (469 were normal, 88 with impaired glucose tolerance [IGT], and 62 with diabetes). Results Area under ROC curve of HbA1c was not different from that of FPG. Area under curve of fructosamine was significantly smaller than that of FPG. For all tests, overall efficacy of a test to detect IGT and diabetes was considerably diminished compared with detection of diabetes alone. Conclusions The discriminating ability of HbA1c is almost the same as that of FPG, therefore HbA1c is a good alternative to FPG. Fructosamine is not suitable for diabetes screening.