Racial/ethnic and sex differences in the ability of metabolic syndrome criteria to predict elevations in fasting insulin levels in adolescents

Abstract

Objective: To evaluate racial/ethnic and sex differences in the relationship between metabolic syndrome (MetS) diagnosis and fasting insulin in adolescents.

Study design: We analyzed data from the National Health and Nutrition Evaluation Survey 1999-2008 for 3693 non-Hispanic-white, non-Hispanic-black, and Hispanic adolescents (12 to 19 years of age). We used linear regression to evaluate differences in fasting insulin levels between those with and without an adolescent adaptation of ATPIII-MetS in a sex- and race/ethnicity-specific basis.

Results: Females had higher insulin levels than males, and non-Hispanic blacks and Hispanics had higher levels than non-Hispanic whites. Adolescents with MetS had higher insulin levels than those without MetS. The difference in insulin levels between those with and without MetS was greater in non-Hispanic blacks than in non-Hispanic whites (P < .05) but not Hispanics (P = .10). The sensitivity of MetS in detecting elevated insulin levels was lower in non-Hispanic blacks and females than in other ethnicities and males, respectively. Correlations between insulin and individual MetS components were similar among ethnicities.

Conclusion: MetS diagnosis performed more poorly in predicting elevated insulin levels in non-Hispanic blacks and in females. These data support the hypothesis that non-Hispanic blacks do not meet current criteria for MetS until they have reached a more advanced degree of insulin resistance.