Purpose: The purposes of this observational prospective study were (a) to identify the prevalence of undiagnosed impaired glucose metabolism (IGM) including impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (T2DM) in 55 Hispanic subjects with two or more risk factors for the metabolic syndrome, (b) to examine the association between glucose metabolism and cardiometabolic risk factors (CMRF), including metabolic syndrome components, and (c) to identify predictors of IGM.
Data sources: Subjects underwent a physical examination and a 2-h 75-g oral glucose tolerance test. Data were analyzed using SAS v9.1 with p < or = .05 considered significant. Nonparametric tests were applied including Mann-Whitney-Wilcoxon test and Spearman correlation coefficient. Stepwise logistic multiple regression was used to predict IGM.
Conclusions: Twenty-five patients (46%) had IGM (18% IFG, 15% IGT, and 13%T2DM). Normal fasting glucose was found in 48% of subjects who had IGM. Lipid abnormalities were present in 98% including elevated triglycerides (TG 66%), total cholesterol (48%), low-density lipoprotein (68.8%), and low high-density lipoprotein (67.9%). Twenty-nine percent had body mass index (BMI) >25 kg/m(2) and 62% had BMI >30 kg/m, hypertension (24%), and elevated high-sensitivity C-reactive protein (63%), and mean number of cardiometabolic risk factors (#CMRF) was 4.5. Mean values for each risk factor were no different between groups except for #CMRF (p = .0001) and TG (p = .0001). Total #CMRF was the best predictor of IGM.
Implications for practice: The prevalence of IGM is extremely high in Hispanics with metabolic syndrome. Screening for IGM with fasting blood glucose alone underestimates the prevalence of IGM in this population. In subjects with multiple CMRF, screening at lower levels of BMI is warranted.