Associations between metabolic syndrome components and prevalent ischemic h
eart disease (IHD) were investigated in a cross-sectional, community-based
study of elderly men (n = 1,015) and women (n = 1,259) in Rancho Bernardo,
California, in 1984-1987. In both sexes, there were significant positive as
sociations between IHD defined by resting electrocardiogram criteria and ag
e, systolic blood pressure, fasting and postchallenge hyperglycemia, total
cholesterol/high density lipoprotein cholesterol (HDL cholesterol) ratio, a
nd triglycerides and an inverse significant association with HDL cholestero
l. High collinearity and interactions between serum insulin and metabolic s
yndrome variables were accounted for by uncorrelated principal components i
dentified by factor analysis. In both men and women, three uncorrelated pri
ncipal components were identified, representing a central metabolic factor
(body mass index, fasting and 2-hour serum insulin, high serum triglyceride
s, and low HDL cholesterol), a glucose factor, and a blood pressure factor.
In a multivariate model with age and sex, all three factors were significa
ntly associated with IHD by electrocardiogram criteria; central metabolic f
actor (odds ratio (OR) = 1.6, p = 0.001), glucose factor (OR = 1.4, p < 0.0
01), blood pressure factor (OR = 1.2, p = 0.005), age (10 years) (OR = 1.8,
p < 0.001), and female sex (OR = 0.5, p < 0.02). Similar results were obta
ined in analyses using clinically manifest IHD as the outcome. These result
s support the thesis that the metabolic syndrome exerts effects through dif
ferent risk factors by different mechanisms.