Usefulness of red cell distribution width in predicting all-cause long-term mortality after non-ST-elevation myocardial infarction.

BACKGROUND: Red blood cell distribution width (RDW) is a strong predictor of adverse outcomes in patients with heart failure, stable coronary artery disease, stroke and acute myocardial infarction. The aim of our study was to explore the predictive value of RDW on all-cause mortality in patients with non-ST-segment elevation myocardial infarction (NSTEMI).

METHOD: This observational study includes 619 NSTEMI patients, discharged from Staten Island University Hospital between September 2004 and December 2006. Patients were divided into equal RDW tertiles and survival was evaluated in each tertile.

RESULT: Patients in the highest RDW tertile (RDW >14) had higher in-patient (7 vs. 1%) and 4-year (30 vs. 7%) mortality rates compared to those in the lowest tertile (RDW <13) (Wilcoxon χ(2) = 34.64, p < 0.0001). After controlling for Global Registry of Acute Coronary Events risk profile scores and other confounding variables, the RDW adjusted hazard ratio for 4-year all-cause mortality increased by 1.10 for each one unit increase in RDW (confidence interval 1.004-1.213, p = 0.042).

CONCLUSION: RDW is an independent predictor of all-cause long-term mortality in NSTEMI patients. Further studies are needed to clarify the mechanisms of this association between RDW and adverse outcomes in patients with coronary artery disease.