Association between neutrophil-to-lymphocyte ratio and early renal function decline in patients with immunoglobulin a...

IgA nephropathy (IgAN) is a chronic immune-mediated progressive kidney disease. The Neutrophil-To-Lymphocyte Ratio (NLR) has emerged as a novel marker for systemic immune inflammation. This study aimed to explore the relationship between NLR and early renal function decline in patients with IgAN.

A real-world cross-sectional observational study was conducted on a cohort of 1073 patients diagnosed with IgAN. Patients were stratified into high and low NLR groups based on a predefined cut-off value. We examined the association between NLR levels and reduced renal function across these groups, defined as an estimated glomerular filtration rate (eGFR) of 60 mL/min·1.73 m² or less, using receiver operating characteristic (ROC) curve analysis and Logistic regression models.

Among the 1,073 patients evaluated, those with an eGFR ≤ 60 mL/min·1.73 m² had significantly higher NLR levels compared to those with eGFR > 60 mL/min·1.73 m² (Z = 9.598, p < 0.001). The area under the AUROC for NLR was 0.671 (p = 0.000, 95% CI: 0.638-0.703). The high NLR group showed significantly elevated levels of mean arterial pressure, 24-hour urinary protein and uric acid, along with lower hemoglobin, serum albumin, and eGFR (all p < 0.001). Multivariate logistic regression analysis revealed that high NLR was independently associated with reduced eGFR (≤ 60 mL/min·1.73 m²) (p = 0.009, OR = 2.110, 95% CI: 1.208-3.683). A nomogram was developed to identify IgAN patients with reduced eGFR (≤60 mL/min·1.73 m²).

IgAN patients with higher NLR levels exhibited more severe clinical manifestations. A high NLR may be associated with an increased risk of eGFR ≤ 60 mL/min·1.73 m² in patients with IgAN.