Agreement of two metabolic syndrome definitions and their association with subclinical atherosclerosis: multi-ethnic study of atherosclerosis cross sectional study.
BACKGROUND
The metabolic syndrome (MetS) is a cluster of abnormalities that increases cardiovascular risk. Two different current clinical definitions of MetS, World Health Organization (WHO) and National Cholesterol Education Program (NCEP) Adult Treatment Panel 3 (ATPIII) may differ in association with the atherosclerotic process. We quantified the agreement between the WHO and NCEP definitions and their association with subclinical atherosclerosis in the Multi-Ethnic Study of Atherosclerosis (MESA).


METHODS
We analyzed 2601 Caucasian-Americans (C), 800 Chinese-Americans (Ch), 1864 African-Americans (A), and 1483 Hispanic-Americans (H) with complete data for MetS classification from the baseline of the population-based study MESA. Coronary artery calcification (CAC, Agatston score) was quantified by electron beam or helical computed tomography (CT), and intimal-medial thickness of internal and common carotid arteries (IIMT, CIMT) by B-mode ultrasound.


RESULTS
The percentage positive agreement differed by ethnicity (Men: C, 65%; Ch, 58%; B, 67%; H, 74%. Women: C, 58%; Ch, 67%; A, 69%; H, 71%; P < .001). Fasting insulin measurement added to the association of the NCEP definition with presence of CAC (P < .001) and CIMT (P < .001, men; P < .002, women), while the waist-hip ratio metric of obesity adds to the association with CIMT (P < .001, men; .003, women). The NCEP threshold for low HDL was associated with CIMT independent of the WHO definition (men, P = .035; women, P = .043). These independent associations did not differ by ethnicity.


CONCLUSIONS
Metabolic risk factors that differ between the NCEP and WHO MetS definitions are useful in combination to assess the presence of subclinical atherosclerosis.
Vaidya
Dhananjay
D
Johns Hopkins University, School of Medicine, Baltimore, MD.
Szklo
Moyses
M
Ding
Jingzhong
J
Tracy
Russell
R
Liu
Kiang
K
Saad
Mohammed
M
Ouyang
Pamela
P