Background: The purpose of this study was to determine the predictive ability of neutrophilia, lymphocytopenia, and neutrophil-lymphocyte ratio (NLR) for overall mortality after EVAR for AAA.
Methods: Data on patients with AAA treated by EVAR between March 2012 and December 2016 were obtained from a prospectively maintained EVAR database at Tokyo Medical University Hospital, Tokyo, Japan. The NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. A cut-off value of total WBC count, neutrophil count, lymphocyte count, and NLR was determined according to a receiver operating characteristic (ROC) curve. Univariate and multivariate analyses were performed using the Cox proportional hazard analyses to account for the time at risk.
Results: One hundred seventy-eight patients were included in this study after selection based on the exclusion criteria. The subjects consisted of 150 men and 28 women with a mean age of 77.5 years (range: 51-89 years). A ROC curve analysis determined the optimal cut-off values of preoperative total WBC, neutrophils, lymphocytes, and NLR for predicting overall mortality with 7,050 /μL, 4,012 /μL, 1,312 /μL, and 3.19, respectively. On univariate and multivariate analyses, octogenarian, obesity, COPD, active cancer, and lymphocytopenia or NLR were detected as independent predictors for overall mortality.
Conclusions: Specific leukocyte populations, such as lymphocyte count and NLR, are useful biomarkers to predict overall mortality in patients undergoing EVAR for AAA, suggesting that WBC count and its subsets, which are easy to perform a test, may be used to stratify patients at risk for poor prognosis following EVAR.