Increased cardiovascular mortality in subjects with metabolic syndrome is largely attributable to diabetes and hypertension in 159 971 Korean adults

Context: Metabolic syndrome (MetS) is a risk factor for cardiovascular disease (CVD) mortality. Objective: This study aimed to evaluate the association of MetS with all-cause and cardiovascular mortality in apparently healthy young Korean subjects. Design: A retrospective study of 155 971 participants (mean age, 41.8 y) in a health screening program, followed up for 3.7 years (597 628.2 person-years). The risk for all-cause mortality and CVD mortality were analyzed according to the presence or absence of MetS. Main Outcomes: A total of 542 subjects died during followup. Women with MetS showed a significantly increased age-adjusted hazard ratio (HR) for all-cause mortality compared with women without MetS, even after adjustment for confounding factors (HR, 1.82; 95% confidence interval [CI], 1.15-2.88). Subjects with MetS showed a significantly increased risk for CVD mortality compared with those without MetS, even after adjustment for confounding factors (HR, 1.60; 95% CI, 1.02-2.20), of which significance disappeared when subjects with diabetes or hypertension at baseline were excluded from the analysis (HR, 0.95; 95% CI, 0.29-3.12). Conclusions: The presence of MetS increased the risk for all-cause mortality in women and the risk for CVD mortality in total population. These increased HR attributed to the pre-existing diabetes or hypertension in this population.