Does Elevated Plasma Triglyceride Level Independently Predict Impaired Fasting Glucose?

OBJECTIVE Elevated plasma triglycerides (TGs) have been included in diabetes risk prediction models. This study examined whether elevated TGs predict risk for impaired fasting glucose (IFG). RESEARCH DESIGN AND METHODS This study used the baseline and longitudinal follow-up data from the Multi-Ethnic Study of Atherosclerosis (MESA). The analysis included non-Hispanic whites, African Americans, Hispanics, and Chinese Americans 45-84 years of age who had fasting glucose <100 mg/dL at baseline and who did not have clinically evident cardiovascular disease or diabetes. Cox proportional regression models were used to examine the association of elevated TGs with incidence of IFG adjusting for central obesity, low HDL cholesterol, elevated blood pressure, baseline fasting glucose, and BMI. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of elevated TGs in predicting IFG were calculated. RESULTS The incidence rate of developing IFG was 59.1 per 1,000 person-years during the median 4.75 years of follow-up. African Americans and Hispanics had a higher incidence rate of IFG compared with non-Hispanic whites among people with normal TG concentrations. Elevated TGs (>150 mg/dL) at baseline were independently associated with the incidence of IFG with an adjusted hazard ratio of 1.19 (95% CI 1.04-1.37). However, its predictive value for identifying people at risk for IFG was poor, with <57% AUC. Interactions of elevated TGs with race/ethnicity in predicting IFG were not statistically significant. CONCLUSIONS Elevated TGs were moderately associated with risk for IFG, and it was a poor risk prediction tool for IFG.