An Exploratory Analysis of Criteria for the Metabolic Syndrome and Its Prediction of Long-term Cardiovascular Outcomes

Cynthia J. Girman, Jacqueline M. Dekker, Thomas Rhodes, Giel Nijpels, Coen D. A. Stehouwer, Lex M. Bouter, Robert J. Heine
2005 American Journal of Epidemiology  
Studies have shown an increased risk of cardiovascular outcomes with the metabolic syndrome, but information on predictive properties of the National Cholesterol Education Program Adult Treatment Panel 3 (NCEP) criteria is sparse. The authors used data from the Hoorn population-based study in the Netherlands including 2,484 participants aged 50-75 years examined in 1989 and followed for cardiovascular morbidity and mortality through 2000 to assess NCEP criteria, excluding known diabetes or
more » ... wn diabetes or cardiovascular disease. Cluster analyses explored whether NCEP identifies a mixture of heterogeneous groups. For each gender, participants meeting NCEP criteria seemed to be divided into clusters distinguished primarily by triglycerides or high density lipoprotein cholesterol. Cutpoints for components predicting cardiovascular events using classification and survival tree methodology varied by endpoint and gender, but Cox model hazards ratios were relatively comparable regardless of cutpoints (range: 1.3-2.5). Clear gradation in risk of cardiovascular outcomes was evident with increasing number of components, with statistically elevated risk for 3 (NCEP) components in men but for 2 components in women. Exploratory analyses of alternative metabolic syndrome criteria suggest cardiovascular risk estimates comparable to those derived by using NCEP, but criteria evaluating risk on more of a continuum would potentially allow consideration of alternative definitions by gender or for patients with other risk factors. aje.oxfordjournals.org Downloaded from Metabolic Syndrome and Cardiovascular Outcomes 441 Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from * Significant nonlinearity in relation to the endpoint. y The value following / was a secondary cut. z HDL, high density lipoprotein. § Subscripts for models with all components considered simultaneously (bottom half of the table) refer to order of entry in the tree-based model. { Not entered into the model (cutpoint not identified). 442 Girman et al. Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from * Comparable results were found for cardiovascular mortality. y HR, hazard ratio; CI, confidence interval; NCEP, National Cholesterol Education Program Adult Treatment Panel 3. z Adjusted for age and smoking. § Hazard ratio is per-unit increase in score, except for the score collapsed into three categories, where the lowest category serves as the reference for the hazard ratio. { A weighted score of the number of components, with waist circumference and hypertension in men or hypertension and high density lipoprotein cholesterol in women weighted twice as much as the other components. Metabolic Syndrome and Cardiovascular Outcomes 443 Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from FIGURE 2. Kaplan-Meier survival curves for the composite cardiovascular endpoint: a) men by metabolic syndrome (no/yes), b) men by number of components of the syndrome (0, 1, 2, 3, 4þ), c) women by metabolic syndrome (no/yes), and d) women by number of components of the syndrome (0, 1, 2, 3, 4þ), Hoorn population-based study initiated in the Netherlands in 1989 with follow-up through 2000. 444 Girman et al. Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from Metabolic Syndrome and Cardiovascular Outcomes 445 Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from Metabolic Syndrome and Cardiovascular Outcomes 447 Am J Epidemiol 2005;162:438-447 at Vrije Universiteit -Library on April 17, 2011 aje.oxfordjournals.org Downloaded from
doi:10.1093/aje/kwi229 pmid:16076828 fatcat:abiody3tnbhmrhm3tmw25wmfui