Neutrophil-to-lymphocyte ratio as a prognostic biomarker in patients with peripheral artery disease: A systematic review and meta-analysis
Roy Bagus Kurniawan, Paulus Parholong Siahaan, Pandit Bagus Tri Saputra, Jannatin Nisa Arnindita, Cornelia Ghea Savitri, Novia Nurul Faizah, Luqman Hakim Andira, Mario D’Oria, Johanes Nugroho, Firas Farisi Alkaff
Abstract
BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) is a simple and routinely obtained parameter reflecting systemic inflammation, including in peripheral artery disease (PAD). METHODS: This systematic review aimed to assess the role of NLR as a prognostic biomarker in patients with PAD. A systematic search was conducted across PubMed, ScienceDirect, Web of Science, Scopus, ProQuest, EBSCO, and Cochrane. Random-effects meta-analysis was used to pool risk ratios, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). A bivariate model was used to generate summary receiver operating characteristics with the corresponding area under the curve (AUC). RESULTS: This review included 5243 patients with PAD from nine eligible studies. High NLR corresponded to at least a twofold increased risk of all-cause mortality (ACM), major adverse limb events (MALE), and major adverse cardiovascular events (MACE). NLR's performance was good for predicting 1-year ACM (AUC 0.71 [95% CI: 0.59-0.79], sensitivity 58.2% [95% CI: 45.3-71.0], specificity 72.6% [95% CI: 65.6-79.62], PPV 41.0% [95% CI: 31.2-50.7], NPV 82.7% [95% CI: 74.1-91.3]) and 1-year MALE (AUC 0.78 [95% CI: 0.75-0.80], sensitivity 65.4% [95% CI: 41.6-89.2], specificity 77.7% [95% CI: 71.0-84.3], PPV 53.7% [95% CI: 47.3-60.1], NPV 83.91% [95% CI: 73.2-94.6]). However, these values tended to decrease as the follow-up duration extended, except for the pooled specificities, which exhibited the opposite pattern. CONCLUSION: .