Is There a Single Underlying Factor for the Metabolic Syndrome in Adolescents?
A confirmatory factor analysis
- Chaoyang Li, MD, PHD and
- Earl S. Ford, MD, MPH
- From the Division of Adult and Community Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
- Address correspondence and reprint requests to Chaoyang Li, MD, PhD, Centers for Disease Control and Prevention, 4770 Buford Highway, MS K66, Atlanta, GA 30341. E-mail: cli{at}cdc.gov
Abstract
OBJECTIVE—The lack of a universally applicable model for the metabolic syndrome in the pediatric population makes it difficult to define this syndrome and compare its prevalence across studies and diverse populations. We sought to assess whether a single underlying factor could represent the metabolic syndrome in adolescents.
RESEARCH DESIGN AND METHODS—Using data from the National Health and Nutrition Examination Survey (1999–2002), we conducted a confirmatory factor analysis to assess the validity of waist circumference, triglycerides, fasting insulin, and systolic blood pressure (SBP) as potential phenotypic traits for the metabolic syndrome in adolescents aged 12–17 years (n = 1,262). A multiple-group approach was used to test the invariance in factor loadings across sex and race/ethnicity.
RESULTS—The estimates of factor loadings for the total sample were 0.76, 0.46, 0.81, and 0.42 for waist circumference, triglycerides, fasting insulin, and SBP, respectively. The goodness-of-fit indexes were adequate for the total sample (comparative fit index, 0.99; standardized root mean square residual, 0.02), Caucasian boys (1.0; 0.01), African-American boys (0.99; 0.03), Mexican-American boys (1.0; 0.01), Mexican-American girls (1.0; 0.01), and Caucasian girls (0.95; 0.04) and acceptable for African-American girls (0.94; 0.05). There were no significant differences in factor loadings of the four measured variables between boys and girls and among the three racial or ethnic subgroups.
CONCLUSIONS—The metabolic syndrome as a single underlying factor for the four simple phenotypic traits may be plausible in adolescents. The proposed model appears to be generalizable across sex and race/ethnicity.
- CFA, confirmatory factor analysis
- CFI, comparative-fit index
- DBP, diastolic blood pressure
- HOMA-IR, homeostasis model assessment of insulin resistance
- MAP, mean arterial pressure
- SBP, systolic blood pressure
Footnotes
-
Published ahead or print at http://care.diabetesjournals.org on 15 March 2007. DOI: 10.2337/dc06-2481.
The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances.
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
-
- Accepted March 4, 2007.
- Received December 6, 2006.
- DIABETES CARE
