INTRODUCTION/OBJECTIVES: Current screening guidelines for pre-diabetes and type 2 diabetes mellitus note that there are discrepancies in diagnosing the disease using the fasting plasma glucose test, oral glucose tolerance test, and HbA1c in high-risk populations. The objective of this study is to compare the effectiveness of screening methods for type 2 diabetes mellitus (T2DM) and pre-diabetes by race/ethnicity and gender. METHODS: Secondary analyses of the National Health and Nutrition Examination Survey (NHANES, 2005-2008) were performed using SPSS 19.0. Screening outcomes were assessed and compared for a sample of n=10,566, NHW, NHB, MA, and Multiracial/other men and women. Analyses included cross tabulations, ANOVA and partial correlations to establish disease prevalence, effectiveness of screenings, and statistical significance. RESULTS: It was found that the HbA1c test is comparable in precision, and is correlated with the FPG for racial and ethnic minorities. The specificities for detecting pre-diabetes using the HbA1c were higher (64-66%) for these groups than by using the standard, FPG screening method (42-49%). There were no strong, significant differences for screening effectiveness for men versus women. DISCUSSION: This study revealed that the HbA1c test might be an effective method for screening for pre-diabetes in racial and ethnic minorities instead of the FPG test alone. Screening in high-risk populations will help delay the onset of T2DM, with increased prevention during the pre-clinical phase.

Current screening tests for type 2 diabetes mellitus (T2DM) identify less than 50% of undiagnosed T2DM patients and provide no information about how the disease will develop in prediabetic patients. Here, twenty-nine protein glycation sites were quantified after tryptic digestion of plasma samples at the peptide level using tandem mass spectrometry and isotope-labelled peptides as internal standard. The glycation degrees were determined in three groups, i.e., 48 patients with a duration of T2DM exceeding ten years, 48 non-diabetic individuals matched for gender, BMI, and age, and 20 prediabetic men. In long-term controlled diabetic patients, 27 glycated peptides were detected at significantly higher levels, providing moderate diagnostic accuracies (ACCs) from 61 to 79%, allowing a subgrouping of patients in three distinct clusters. Moreover, a feature set of one glycated peptides and six established clinical parameters provided an ACC of 95%. The same number of clusters was identified in prediabetic males (ACC of 95%) using a set of eight glycation sites (mostly from serum albumin). All patients present in one cluster showed progression of prediabetic state or advanced towards diabetes in the following five years. Overall, the studied glycation sites appear to be promising biomarkers for subgrouping prediabetic patients to estimate their risk for the development of T2DM.