Prognostic significance of an elevated neutrophil-lymphocyte ratio in the amputation-free survival of patients with chronic critical limb ischemia.

BACKGROUND

The aim of this study was to investigate the utility of admission neutrophil-lymphocyte ratio (NLR) in predicting the amputation-free survival (AFS) of patients with critical limb ischemia (CLI) who underwent an elective infrainguinal therapeutic intervention.

METHODS

All patients with CLI undergoing elective infrainguinal vascular surgery (open or endovascular) at a single university teaching hospital between January 2005 and December 2009 were retrospectively identified from a prospectively maintained database. The primary end point was AFS. The cut-off of NLR >5 was used to categorize patients into low- and high-NLR groups. Kaplan-Meier analysis and long-rank test were used to compare survival between both groups. Cox regression analysis was conducted to determine independent factors affecting the AFS.

RESULTS

During a median follow-up of 31 months, 561 patients with chronic CLI underwent infrainguinal revascularization. Five-year mortality was lower in the NLR <5 group (33%) than in the NLR >5 group (49%) (P ≤ 0.001), and the AFS was significantly higher in the NLR <5 group (50%) than in the NLR >5 group (26%) (P ≤ 0.001). In a multivariate analysis, preoperative NLR >5 was independently associated with 5-year AFS (hazard ratio 2.325, 95% CI 1.732-3.121).

CONCLUSIONS

Elevated NLR predicts a worse AFS in patients undergoing infrainguinal vascular revascularization with chronic CLI, suggesting that the NLR conveys powerful prognostic information that is independent of other conventional clinical risk factors.