Purpose: ATP III defined metabolic syndrome (MetS) as at least three of five criteria (waist circumference [WC], elevated fasting glucose [FG], low HDL [HDL], high triglycerides [TG], elevated blood pressure [BP]). We developed a novel score to account for the differing all-cause mortality hazards of individual criteria and to better reflect the increased mortality with increasing number of criteria.
Methods: A population of 2,392 non-pregnant individuals >20 years with data on demographics, MetS criteria, smoking status, and mortality were included in this secondary analysis of NHANES III (1988-1994). Outcomes included all-cause mortality as of Dec. 31st, 2011. Cox hazard models were run adjusting for potential confounders and accounting for the complex survey design. Hazard weights for each criterion were developed using univariate Cox models and summed for an overall score.
Results: There were 991 deaths from all causes among the 2,393 individuals over 250-months. Among those with MetS, increasing number of criteria coincided with increasing mortality hazards compared to those with 0 criteria (3: aHR=1.47, 95% CI [1.18, 1.83]; 4: aHR=1.77 [1.42, 2.21]; 5: aHR=2.39 [1.89, 3.02]). In our model individual criterion mortality hazards were rounded and assigned as points. The sum of the points of the criteria formed a weighted score. From highest to lowest hazard, the criteria hierarchy was BP (5 points), FG (3), WC (2), TG (1), and HDL (1) for a total possible score of 12 points. Scores 6 points and above had similar or higher hazard to those with traditional MetS when compared to normals (Score of 6: aHR= 1.50 [1.20, 1.88] vs. MetS: aHR: 1.29 [1.17, 1.42]). Increasing points corresponded to increasing mortality hazard; those with 10-12 points had nearly double the hazard as normals (aHR= 2.07 [1.54, 2.79]).
Conclusion: The developed weighted score is a more comprehensive ranking which assesses aggregate mortality hazard and may better assess all-cause mortality hazard in U.S. adults than current MetS diagnostic criteria.
A. Visaria: None. L.F. Amorosa: None.