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.
Keywords: abdominal aortic aneurysm; endovascular aortic repair; lymphocyte-monocyte ratio; survival.