Cardiovascular risk factors clustering features of insulin resistance syndrome (Syndrome X) in a biracial (Black-White) population of children, adolescents, and young adults - The Bogalusa Heart Study

Recently, independent factors representing different features of insulin re sistance syndrome (Syndrome X) have been identified by factor analysis in m iddle-aged and elderly adult populations. In this study, factor analysis wa s applied to the clustering characteristics of Syndrome X in a biracial (Bl ack-White) community-based population of 4,522 children (ages 5-11 years), adolescents (ages 12-17 years), and young adults (ages 18-38 years) from th e Bogalusa Heart Study who were screened during 1988-1996. Ponderal index ( weight (kg)/height (m)(3)), levels of insulin, glucose, triglycerides, and high density lipoprotein cholesterol, and systolic and diastolic blood pres sure were used as measures of components of Syndrome X, No evidence was fou nd to support a one-factor hypothesis for this syndrome, but factor analysi s yielded two uncorrelated factors (factor I: insulin/lipids/glucose/ponder al index; factor 2: insulin/blood pressure). These two factors explained 54 .6% of the total variance in the entire sample. The factor loading patterns were very similar in all race and age groups, based on high values of coef ficients of congruence (0.89-1.0). These results suggest that Syndrome X is characterized by the linking of a metabolic entity (hyperinsulinemia/insul in resistance, dyslipidemia, and obesity) to a hemodynamic factor (hyperten sion) through shared correlation with hyperinsulinemia/insulin resistance, and that the clustering features are independent of sex and age in both Bla ck and White populations.