Objective: This study assessed the mortality risk associated with metabolic syndrome (MetS) for participants from the Third National Health and Nutrition Examination Survey.
Design, setting, and patients: The study analyzed mortality data from 1364 men and 1321 women aged 40 yr and older based on their MetS status defined by National Cholesterol Education Program Adult Treatment Panel III. Subjects initially using insulin, oral hypoglycemic, antihypertensive, or lipid-lowering medications were excluded.
Main outcome measures: All-cause, cardiovascular, cardiac, and noncardiovascular mortality were obtained from the Third National Health and Nutrition Examination Survey-linked mortality follow-up file through December 31, 2000.
Results: The prevalence of MetS was 33 and 29% for men and women, respectively. In the male subjects, there was no significant association between MetS and mortality. In the women, MetS was an independent risk factor for all-cause mortality [hazard ratio (HR) 1.84, 95% confidence interval (CI) 1.29-2.64, P = 0.001], cardiovascular mortality (HR 1.96, 95% CI 1.21-3.17, P = 0.007), cardiac mortality (HR 1.88, 95% CI 1.15-3.09, P = 0.01), and noncardiovascular mortality (HR 1.80, 95% CI 1.13-2.87, P = 0.01). The HR was stronger when postmenopausal women were analyzed separately and became nonsignificant in the premenopausal cohort. The sex-specific HR remained unchanged, regardless of the MetS criteria used or the inclusion of actively treated subjects.
Conclusions: MetS poses a significant increase in mortality risk through an observation period as long as 12 yr, primarily in postmenopausal women, that is not apparent in men and premenopausal women. Sex is an important effect modifier of all-cause and cause-specific death.