Metabolic syndrome vs. its components for prediction of cardiovascular mortality: A cohort study in Chinese elderly adults

Objective The predictive value of the metabolic syndrome (MetS) for mortality from all-cause and cardiovascular disease (CVD) in the Chinese population is unclear. The aim of this present study was to compare MetS with its individual components as predictors of mortality in Chinese elderly adults. Methods A cohort of 1,535 subjects (994 men and 541 women) aged 50 years or older was selected from employees of a machinery factory in 1994 and followed until 2009. Cox models were used to estimate the hazard ratios (HRs) predicted by MetS according to the harmonized definition and by its individual components. Results The baseline prevalence of MetS was 28.0% in men and 48.4% in women. During a median follow-up of 15 years, 414 deaths occurred, of these, 153 participants died from CVD. Adjusted for age and gender, the HRs of mortality from all-cause and CVD in participants with MetS were 1.47 (95% confidence interval (CI): 1.20-1.80) and 1.96 (95% CI: 1.42-2.72), respectively, compared with those without MetS. Non-significant higher risk of CVD mortality was seen in those with one or two individual components (HR = 1.22, 95%CI: 0.59-2.50; HR = 1.82, 95%CI: 0.91-3.64, respectively), while a substantially higher risk of CVD mortality only appeared in those with 3, 4, or 5 components (HR = 2.81-3.72), compared with those with no components. On evaluating the MetS components individually, we found that, independent of MetS, only hypertension and impaired glucose predicted higher mortality. Conclusions The number of positive MetS components seems no more informative than classifying (dichotomous) MetS for CVD risks assessment in this Chinese cohort.