Association of neutrophil-lymphocyte ratio with cardiovascular and all-cause mortality in patients receiving chronic hemodialysis: Systematic review and meta-analysis

The neutrophil-lymphocyte ratio (NLR) has been proposed as a potential prognostic marker for mortality outcomes in various conditions, yet its association with chronic hemodialysis (HD) remains underexplored. We aim to study its utility by conducting a meta-analysis of this specific population. To determine whether elevated NLR is associated with all-cause mortality (ACM) and cardiovascular mortality (CVM) in patients undergoing chronic HD. A comprehensive search from PubMed, Google Scholar, and Scopus identified studies showing the association between NLR and mortality outcomes in patients with chronic HD. Random-effects models with 95%CIs were employed to pool adjusted hazard ratios (aHRs), odds ratios (ORs), and I² statistics for evaluating the heterogeneity of findings. Leave-one-out sensitivity and meta-regression analyses assessed changes in overall effects and identified confounders, respectively. The Joanna Briggs Institute (JBI) tool was used to assess the quality of studies. 19 studies comprising 9047 patients with a mean age of 59.5 ± 5.86 years and a mean follow-up duration of 46.7 months were included in our study. Our meta-analysis revealed a significant association between NLR > 2.5 and increased risks of ACM (aHR: 1.25, 95%CI: 1.14-1.37, P < 0.0001) and CVM (aHR: 1.24, 95%CI: 1.02-1.49, P = 0.03). Studies reporting outcomes in OR reported similar findings for ACM (OR: 4.59, 95%CI: 1.74-12.11, P = 0.002) and CVM (OR: 1.11, 95%CI: 1.01-1.23, P = 0.03). Sensitivity analysis revealed no variations. Meta-regression revealed increasing male proportion is positively associated with ACM. Pooled area under the curve (AUC) was 0.71 (95%CI: 0.63-0.80, P < 0.0001). The JBI tool revealed high-quality studies. This meta-analysis suggests that elevated NLR may serve as a useful prognostic marker for ACM and CVM in patients on chronic HD and can be useful in planning for the prevention of mortality-related strategies.