Prognostic value of neutrophil-to-lymphocyte ratio for the clinical outcomes of chronic kidney diseases: an update systematic review and meta-analysis.

backgroundThe correlation between the neutrophil-to-lymphocyte ratio (NLR) and clinical outcomes in patients with chronic kidney disease (CKD) remains inconsistent.

methodsPubMed, Embase, Web of Science, and the Cochrane Library were searched for relevant literature through March 8, 2025. All-cause mortality, major adverse cardiovascular events (MACE), cardiovascular death, and progression to end-stage renal disease (ESRD) or dialysis were evaluated. Odds ratios (OR) and 95% confidence intervals (CI) were used for effect estimation.

resultsThirty-six studies involving 26,074 patients were included. Meta-analysis indicated that high NLR was significantly associated with an increased risk of all-cause mortality (OR = 1.22, 95% CI: 1.15-1.29; p < 0.00001), MACE (OR = 1.42, 95% CI: 1.14-1.77; p = 0.002), cardiovascular mortality (OR = 1.21, 95% CI: 1.09-1.35; p = 0.0004), and ESRD (OR = 1.68, 95% CI: 1.17-2.43; p = 0.005). NLR levels were significantly higher in patients who died from all causes (SMD = 0.84, 95% CI: 0.58-1.11; p < 0.00001) and cardiovascular causes (SMD = 1.44, 95% CI: 0.77-2.11; p < 0.0001) compared to survivors. Sensitivity and subgroup analyses affirmed the robustness of the results. All indicators were rated as very low in the GRADE system.

conclusionNLR is significantly associated with all-cause mortality, MACE, cardiovascular mortality, and adverse renal outcomes in CKD. The results are relatively stable, but due to high heterogeneity and publication bias, its clinical application should be approached with caution. Given the study's limitations, further large-scale prospective studies are required to confirm the association between NLR and CKD prognosis. CLINICAL TRIAL NUMBER: Not applicable.