Relationship between neutrophil-lymphocyte ratio and severity of lower extremity peripheral artery disease

BACKGROUND:The aim of this study was to determine the association between neutrophil-lymphocyte ratio (NLR) and severity of lower extremity peripheral artery disease (PAD). METHODS:A retrospective chart review identified 928 patients referred for peripheral angiography. NLR was assessed from routine pre-procedural hemograms with automated differentials and available in 733 patients. Outcomes of interest were extent of disease on peripheral angiography and target vessel revascularization. Median follow-up was 10.4months. Odds ratio (OR) [95% confidence intervals] was assessed using a logistic regression model. RESULTS:There was a significant association between elevated NLR and presence of severe multi-level PAD versus isolated suprapopliteal or isolated infrapopliteal disease (OR 1.11 [1.03-1.19], p=0.007). This association remained significant even after adjustment for age (OR 1.09 [1.01-1.17], p=0.02); age, sex, race, and body mass index (OR 1.08 [1.00-1.16], p=0.046); and age, sex, race, body mass index, hypertension, diabetes mellitus, coronary artery disease, and creatinine (OR 1.07 [1.00-1.15], p=0.049). After additional adjustment for clinical presentation, there was a trend towards association between NLR and severe multi-level PAD (OR 1.07 [1.00-1.15], p=0.056), likely limited by sample size. In patients who underwent endovascular intervention (n=523), there was no significant difference in rate of target vessel revascularization across tertiles of NLR (1st tertile 14.8%, 2nd tertile 14.1%, 3rd tertile 20.1%; p=0.32). CONCLUSION:In a contemporary cohort of patients undergoing peripheral angiography with possible endovascular intervention, elevated NLR was independently associated with severe multi-level PAD. Larger studies evaluating the association between this inexpensive biomarker and clinical outcomes are warranted.