Added value of different metabolic syndrome definitions for predicting cardiovascular disease and mortality events among elderly population: Tehran Lipid and Glucose Study

Background/Objectives: To examine the association between the different definitions of metabolic syndrome (MetS) and the prediction of incident cardiovascular disease (CVD) and mortality events and to determine whether the concept of MetS adds to traditional risk factors among elderly Iranians. Subjects/Methods: The association between MetS and outcomes was examined in 922 adults aged ⩾65 years, free of CVD at baseline, using multivariate Cox proportional hazards models. To examine whether MetS could enhance prediction of outcomes beyond that achieved by risk factors; the net reclassification improvement index was used. Results: During a median follow-up of 9.9 years, 207 CVD events and 193 deaths (82 CVD deaths) occurred. World health organization (WHO) and the joint interim statement (JIS) definitions were shown to be the strongest predictors of CVD events. The WHO definition predicted CVD and all-cause mortality events (hazard ratio (HR)=1.55 (95% confidence interval (CI)=1.15–2.09) and 2.08 (95% CI=1.23–3.51), respectively) and the JIS definition showed a risk for CVD mortality (HR=1.65 (95% CI=1.03–2.65)). Different definitions of MetS did not add to traditional risk factors in the prediction of different outcomes. Conclusions: The WHO definition was the strongest predictor of CVD and mortality outcomes; however, none of the MetS definitions provided added value to traditional risk factors.