Post-partum reclassification of glucose tolerance in women previously diagnosed with gestational diabetes mellitus

Aims To re-evaluate post-partum screening; fasting plasma glucose (FPG) vs. oral glucose tolerance test (OGTT) in Caucasian women with previous gestat ional diabetes mellitus (GDM). Methods Once breast-feeding had finished, an OGTT was performed in 120 wome n with previous GDM. They were classified according to World Health Organiz ation (WHO) 1985 and American Diabetes Association (ADA) 1997 criteria. The kappa-statistic measure of agreement was used to compared both diagnostic categories. A receiver-operating characteristic (ROC) curve studied the FPG as a test to detect abnormal glucose tolerance. Results Identical diabetes prevalence (2%) but quite different intermediate categories (12% impaired glucose tolerance vs. 3% impaired fasting glucose ) were observed with both criteria. The kappa-statistic (scaled from 0 to 1 ) was 0.38 (fair agreement), P = 0.000. The ROC curve area of the FPG was 0 .65. Conclusions FPG is an unsatisfactory method of evaluating the glucose toler ance of Caucasian women with previous GDM. OGTT may be a better test for su ch a purpose.