The Preoperative Lymphocyte-To-Monocyte Ratio Predicts Mortality Among Patients Undergoing Endovascular Aortic Repair for Abdominal Aortic Aneurysm

Abstract

Purpose The purpose of this study was to investigate the preoperative lymphocyte-to-monocyte ratio (LMR) as a potential surrogate biomarker predictive of overall mortality in patients undergoing endovascular aortic repair (EVAR) for abdominal aortic aneurysm (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 LMR was calculated by dividing the absolute lymphocyte count by the absolute monocyte count. Results One hundred seventy-six patients were included in this study after selection based on the exclusion criteria. The subjects consisted of 148 males and 28 females with a mean age of 78.5 years (range, 51-89 years). The median follow-up period was 4.98 years (range, .03-9.28). A receiver operating characteristic curve analysis determined the optimal cut-off value of the preoperative LMR for predicting overall mortality with 3.21 (area under the curve, .71; 95% confidence interval [CI], .62-.79; sensitivity, 57.4%; specificity, 77.0%; P < .001). On univariable and multivariable analyses, octogenarian (hazard ratio [HR], 1.89; 95%CI, 1.10-3.22; P = .020), poor nutritional status (HR, 2.95; 95%CI, 1.73-5.03; P < .001), chronic obstructive pulmonary disease (HR, 1.79; 95%CI, 1.06-3.03; P = .031), active cancer (HR, 2.60; 95%CI, 1.53-4.41; P < .001), and low preoperative LMR (HR, 2.56; 95%CI, 1.53-4.30; P < .001) were identified as independent predictors for overall mortality. Conclusion This study showed that a low preoperative LMR (<3.21) is an independent predictor of overall mortality after EVAR for AAA. The LMR may help in decision-making regarding the prediction of poor prognosis after EVAR.