Background: Metabolic syndrome (MetS), a clustering of several prominent risk factors for atherosclerosis, is common among U.S. populations. The contribution of MetS to the prevalence of coronary heart disease (CHD) in different age-gender groups is currently unknown.
Methods: MetS was defined according to the definition of the National Cholesterol Education Program Adult Treatment Panel III. CHD was defined as having had a diagnosed heart attack in self-reported medical history. Data from the Third National Health and Nutrition Examination Survey (NHANES III) were used to evaluate the MetS-associated CHD prevalences in different age-gender subpopulations, which include 35- to 54-year-old women, 55- to 74-year-old women, 35- to 54-year-old men, and 55- to 74-year-old men.
Results: The prevalences of MetS in these 4 age-gender subpopulations are 21%, 24%, 39%, and 38%, respectively. The odds ratios (and the 95% confidence intervals) of MetS to increased CHD in each subpopulations are 1.05 (0.40-2.79), 1.95 (1.19-3.20), 2.22 (1.03-4.81), and 1.96 (1.41-2.70), respectively.
Conclusions: MetS-associated CHD prevalence in women aged 35-54 years is almost the same as in the control, whereas in women aged 55-74 and in men aged 35-54 or 55-74, this prevalence is about 2-fold that of the control. Endogenous estrogen may play a role in suppressing the pro-atherosclerotic effects of MetS-related risk factors, but further studies are needed for a more certain conclusion.