Neutrophil to Lymphocyte Ratio as a Predictor of Long‐term Mortality in African Americans Undergoing Percutaneous Coronary Intervention

Background Neutrophil to lymphocyte ratio (N/L ratio) has been shown to predict long‐term mortality in patients undergoing percutaneous coronary intervention (PCI). African Americans have been shown to have lower mean neutrophil counts compared to whites. The usefulness of the N/L ratio in predicting long‐term mortality in African Americans undergoing PCI is unknown. Methods We evaluated a total of 372 African American patients (327 patients with lower N/L ratio [<3.5] and 45 patients with higher N/L ratio [≥3.5]) who underwent PCI during January 2003 to August 2005. The primary endpoint was all‐cause mortality at a median follow‐up to 3.6 years. Results During the median ( ± SD) follow‐up period of 3.6 ± 1 years, there were a total of 48 deaths. The mortality rate was 10.4% in the group with a lower N/L ratio and 31.1% in the group with a higher N/L ratio (unadjusted p < 0.001). After adjustment for covariates with significant impact on mortality, N/L ratio was still a strong and independent predictor of long‐term mortality with a hazard ratio (HR) of 2.1 (95% confidence interval [CI]: 1.1–4; p = 0.02). N/L ratio was also found to be a strong and independent predictor of long‐term mortality even when analyzed as a categorical variable with 3 groups (HR of 0.39 for lower tertile compared to the upper tertile, 95% CI: 0.19–0.81; p = 0.012) and as a continuous variable (p = 0.002). Conclusion N/L ratio is a powerful independent predictor of long‐term mortality in African Americans undergoing PCI. Copyright © 2009 Wiley Periodicals, Inc.