Abstract 16797: Red Cell Distribution Width and Risk of Coronary Heart Disease Among Low Risk Healthy Representative US Adults
Objective: Evaluate the risk reclassification properties of red cell distribution width (RDW) in low risk healthy population free of prior cardiovascular disease (CVD) and diabetes.
Background: Red cell distribution width (RDW) is an independent predictor of future CVD events. No prior study has evaluated whether addition of RDW to traditional cardiovascular risk factors (CVRF) (age, male sex, hypertension, dyslipidemia and smoking) improves risk reclassification, especially for those at intermediate risk of CVD events.
Study Type: Prospective observational
Methods: 15,460 participants aged ≥20 years of National Health and Nutrition Examination Survey (1988 to 1994) were evaluated. Adjusted Cox-proportional hazard analyses were performed to evaluate independent association between RDW and cardiovascular deaths (CVD and coronary heart disease (CHD)) beyond traditional CVRF, C-reactive protein, estimated glomerular filtration rate, hemoglobin, mean corpuscular volume and deficiency of nutritional factors like iron, folate and vitamin B12. Various calibrative and discriminatory methods were used to evaluate model with RDW and CVRF compared to model with CVRF alone. Newer reclassification index, category-less net reclassification improvement (NRI), was computed to analyze reclassification properties of RDW over traditional CVRF.
Results: RDW independently predicted CVD (adjusted hazard ratio (aHR): 2.18, 95% Confidence interval (CI) - 1.70 to 2.82, p<0.001) and CHD (aHR 2.15, 95% CI - 1.61 to 2.88, p<0.001) mortality after adjustments. Statistically favored model including RDW and traditional CVRF reclassified 74% of overall population (95% CI - 65% to 85%, p<0.001) based on category-less NRI. Nearly 35% of those classified to have intermediate risk by traditional CVRF were reclassified into higher or lower risk categories by addition of RDW.
Conclusion: In this nationally representative adult US population, RDW significantly improves risk reclassification beyond traditional CVRF.
- © 2011 by American Heart Association, Inc.