Analysis of the Predictive Value of Neutrophil-to-Lymphocyte Ratio for Long-term Survival After Endovascular Abdominal Aortic Aneurysm Repair: A Single-Center Retrospective Study and Propensity Score Matching Validation.

OBJECTIVE: To investigate factors influencing long-term survival in abdominal aortic aneurysm (AAA) patients following endovascular aneurysm repair (EVAR), and analyze the predictive value of the neutrophil-to-lymphocyte ratio (NLR). METHODS: A retrospective study was conducted on patients who underwent elective EVAR at our hospital between 2012 and 2021. Included patients had complete preoperative hematologic examinations, available postoperative follow-up data, and were excluded if they had symptomatic, infected/ruptured aneurysms or an American Society of Anesthesiologists (ASA) class five. Kaplan-Meier curves with log-rank test, Cox proportional hazards regression, ROC curves and propensity score matching (PSM) were adopted for survival analysis, risk factor identification, optimal NLR cutoff determination and confounding control, respectively. RESULTS: A study was conducted with a total of 537 participants, and 84% were male. During follow-up, 140 individuals (26%) died. Cox regression identified independent survival predictors: age (HR, 1.060; 95%CI, 1.038-1.081; P<0.001), peripheral artery disease (PAD) (HR, 3.133; 95%CI, 1.629-6.025; P=0.001), smoking (HR, 1.528; 95%CI, 1.010-2.311; P=0.045), ASA classification (HR, 2.931; 95%CI, 1.906-4.507; P=0.001), aneurysm diameter (HR, 1.181; 95%CI, 1.064-1.312; P=0.002), and NLR (HR, 1.103; 95%CI, 1.061-1.147; P<0.001). The NLR had an optimal cutoff value of 3.89 based on the ROC curve analysis. Patients in the high NLR group had significantly lower overall survival time. This difference remained statistically significant after controlling for confounding variables through PSM (P<0.001). CONCLUSION: Age, smoking, PAD, aneurysm diameter, ASA classification, and NLR are associated with long-term survival rates in AAA patients following EVAR. NLR holds significant value in post-EVAR prognostic assessment.