Prevalence of the metabolic syndrome among a racially/ethnically diverse group of U.S eighth-grade adolescents and associations with fasting insulin and homeostasis model assessment of insulin resistance levels

OBJECTIVE—The purpose of this study was to report the prevalence of the International Diabetes Federation (IDF)–defined metabolic syndrome and its components among a cross-sectional sample of racially/ethnically diverse eighth grade youths and examine the association between the presence of the syndrome and participant fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) levels. RESEARCH DESIGN AND METHODS—Data were from a cross-sectional study with 1,453 racially/ethnically diverse eighth grade students from 12 middle schools in three U.S. states (Texas, North Carolina, and California). Height, weight, waist circumference, and blood pressure were recorded. Fasting blood samples were analyzed for triglycerides, HDL cholesterol, glucose, and insulin; HOMA-IR was calculated. Sex, race/ethnicity, and pubertal stage were self-reported. IDF criteria were used to determine the prevalence of the metabolic syndrome. The odds ratio for being classified with the syndrome was calculated by quintiles of fasting insulin and HOMA-IR. RESULTS—Of the sample, 138 students (9.5%) were classified with metabolic syndrome. Hispanics were more likely to have high abdominal adiposity and high triglycerides. Male adolescents were more likely to have high triglycerides, low HDL cholesterol, high blood pressure, and high fasting glucose. Participants in the highest insulin quintile were almost 200 times more likely to be classified with the syndrome than participants in the lowest quintile with comparable associations for HOMA-IR quintiles. CONCLUSIONS—In a racially/ethnically diverse sample of U.S. adolescents, 9.5% of participants were identified with the metabolic syndrome using the IDF criteria. The likelihood of metabolic syndrome classification significantly increased with higher insulin and HOMA-IR values.