Clustering of Long-term Trends in Metabolic Syndrome Variables from Childhood to Adulthood in Blacks and Whites: The Bogalusa Heart Study

Abstract

Clustering of long-term rates of change in metabolic syndrome variables (body mass index, homeostasis model assessment of insulin resistance, ratio of triglycerides to high-density lipoprotein cholesterol, and mean arterial pressure) from childhood to adulthood was evaluated longitudinally (1982–2003) in a cohort of 389 Blacks and 631 Whites who were examined 3–6 times both as children (ages 4–17 years) and as adults (ages 18–38 years) over an average of 16 years (3,874 observations). The incremental area under the growth curve was used as a measure of long-term rates of change in risk variables since childhood. Intraclass correlations, a measure of the degree of clustering, among the four variables were significant (p < 0.001) for childhood, adulthood, and incremental area values and were higher in adulthood than in childhood. Blacks showed a higher degree of clustering of long-term rates of change in risk variables than did Whites. Adjustment for body mass index reduced the degree of clustering by approximately 50%. These results show that metabolic syndrome variables coexist in terms not only of their levels in childhood and adulthood but also of long-term rates of change. Obesity is of critical importance in the development of metabolic syndrome, and its prevention beginning in childhood needs to be addressed.