Should triglycerides and the triglycerides to high-density lipoprotein cholesterol ratio be used as surrogates for insulin resistance?

The aims of the present study were to examine whether triglycerides (TG) and the triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C) could predict insulin resistance in healthy African Americans and whites This cross-sectional study included 99 African American and 50 white men and women between 18 and 45 years of age with body mass indexes between 18 5 and 38 0 kg/m(2). Anthropometric measures were obtained, and overnight fasting blood was collected for TG, HDL-C, glucose, and insulin Insulin resistance was defined by fasting insulin concentration of at least 13.13 mu U/mL and homeostasis model assessment of insulin resistance (HOMA-IR) of at least 2 5 Receiver operating characteristic curves were used to analyze the data African Americans and whites had comparable demographic and anthropometric measures. Fasting insulin was higher in African Americans (12 4 7 8 mu U/mL) than whites (10 2 7 5 mu U/mL). but HOMA-IR did not differ significantly (African Americans, 2 9 2 0, whites, 2 4 :1: I 9) Triglycerides and TG/HDL-C were significantly lower in African Americans (TG, 68.2 +/- 43.3 mg/dL, TG/HDL-C, 1.8 +/- 2.1) compared with whites (TG, 105.4 +/- 55.2 mg/dL, TG/HDL-C, 2 8 1 8). Area under the receiver operating characteristic curves revealed that both TG and TG/HDL-C were acceptable markers of insulin resistance, as defined by fasting insulin concentration, in whites, 0 770 and 0 765, respectively, but poor predictors in African Americans, 0.633 and 0.651, respectively Similarly. TG and TG/HDL-C were acceptable in predicting insulin resistance, as measured by HOMA-IR, in whites, 0.763 and 0.770, respectively, but poor in predicting HOMA-IR in African Americans, with areas of 0.625 and 0.639, respectively In conclusion, the relationship between TO and TG/HDL-C with insulin resistance differs by ethnicity, and using TG and TG/HDL-C to predict insulin resistance in African Americans would not be appropriate (C) 2010 Elsevier Inc All rights reserved