The Predictive Role of NLR and PLR in Outcome and Patency of Lower Limb Revascularization in Patients with Femoropopliteal Disease

Background: Peripheral arterial disease (PAD) changes the arterial structure and function, and is the most common manifestation of the atherosclerotic process, except for the coronary and cerebral arterial systems. Inflammation is well known to have a role in the progression of atherosclerosis and, by extension, in PAD. Among the recently studied markers in the literature, we list the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR). This study aims to analyze the preoperative role of NLR and PLR in the medium-term outcome of patients surgically revascularized for femoropopliteal disease.

Methods: A retrospective study included patients admitted to the Vascular Surgery Clinic of the County Emergency Clinical Hospital of Târgu-Mureș, Romania, between January 2017 and December 2019, diagnosed with femoropopliteal disease and having presented an indication for surgical revascularization. The patients included in the study were classified according to the 12 months primary patency in two groups: "patency" and "nonpatency".

Results: Depending on the Rutherford classification (RC), there was a higher incidence of stages II and III in the patency group and a higher incidence of stage V in the nonpatency group. Depending on the optimal cut-off value according to ROC for the 12 months primary patency, obtained from Youden's index (3.95 for NLR (82.6% sensitivity and 89.9% specificity), and 142.13 for PLR (79.1% sensitivity and 82.6% specificity)), in all high-NLR and high-PLR groups, there was a higher incidence of all adverse outcomes. Moreover, a multivariate analysis showed that a high baseline value for NLR and PLR was an independent predictor of all outcomes for all recruited patients. Furthermore, for all hospitalized patients, RC 5 was an independent predictor of poor prognosis.

Conclusions: Our findings establish that a high value of preoperative NLR and PLR determined at hospital admission is strongly predictive of primary patency failure (12 months after revascularization). Additionally, elevated ratio values are an independent predictor for a higher amputation rate and death for all patients enrolled in the study, except for mortality in RC 2, and both amputation and mortality in RC 5.