High Neutrophil-To-Lymphocyte Ratio Linked to Early Renal Function Decline in IgAN

Findings from a recent study show an association between elevated neutrophil-to-lymphocyte ratio (NLR) levels and reduced renal function in patients with IgA nephropathy (IgAN).1

Investigators gathered data from the Yidu Cloud Research Collaboration Platform to explore the relationship between higher NLR, ≥ 2.375, and early renal decline, defined as an estimated glomerular filtration rate (eGFR) ≤ 60 mL/min·1.73 m2, in patients with IgAN.

“In clinical settings, it has been observed that some IgAN patients exhibit a progressive decline in renal function despite well-managed proteinuria and blood pressure,” wrote Wenjing Zhao MD, Beijing Hospital of Traditional Chinese Medicine, and colleagues. “Extensive research has focused on developing risk models for predicting progression to ESRD in IgAN, but models for early renal function decline, specifically to eGFR ≤ 60 mL/min·1.73 m2, have received less attention.”

Previous retrospective analyses and cohort studies have reported a greater risk for end-stage renal disease in patients with higher NLR, particularly stage 3-4 CKD or 24-hour urinary protein 1/g or more a day. Still, further clinical studies have not addressed the association between NLR and reduced eGFR in IgAN.2

To address this gap in research, investigators conducted a retrospective cross-sectional study to determine whether adding NLR to an IgAN clinical risk model might improve the baseline assessment of early renal function.

The real-world, cross-sectional observational study stratified patients into high and low NLR groups using a cut-off value derived from the Youden Index. The high NLR group was determined as ≥ 2.375, and the low NLR group at ≤ 2.375. During the initial patient encounter, eGFR was calculated, and patients were stratified into 2 groups: a reduced renal function group and those measuring > 60 mL/min·1.73 m2.

The Ethics Committee of Beijing Hospital of Traditional Chinese Medicine approved the study’s inclusion of 1277 biopsy-diagnosed primary IgAN patients from January 2010 to December 2023. The reduced renal function group included 469 patients (43.6%), and the group with standard renal function had 604 patients (56.3%).

Investigators leveraged receiver operating characteristic (ROC) curve analysis and logistic regression models to understand the association between NLR levels and renal function. Then, they computed the NLR, Platelet to Lymphocyte Ratio (PLR), and Systemic Immune-Inflammation Index (SII). The AUCs for each datapoint were: NLR at 0.671 (95% CI, 0.638–0.703; P = .000), PLR at 0.578 (95% CI, 0.544–0.612; P = .000), and SII at 0.568 (95% CI, 0.533–0.602; P = .000). Further exploration of higher NLR and IgAN clinical manifestations revealed mean arterial pressure (P <.001), lower hemoglobin (P <.001), higher 24-hour urinary protein (P <.001), lower serum albumin (P <.001), higher uric acid (P <.001), and lower eGFR (P <.001). High NLR was associated with reduced eGFR (OR, 2.110; 95% CI, 1.208–3.683; P = .009).

Further analysis revealed key characteristics, such as age, MAP, 24-hour urinary protein, hemoglobin, uric acid, and NLR, are independently associated with reduced renal function and lower levels of eGFR. Additionally, patients in the high NLR group demonstrated more severe clinical outcomes, such as significantly lower eGFR, higher proteinuria, lower serum albumin, higher uric acid, higher blood pressure, and lower hemoglobin.

“Our findings suggest that while NLR has moderate predictive value alone, its integration into comprehensive assessment models significantly improves individualized risk stratification for early renal function decline in IgAN patients,” concluded investigators.1 “This supports the potential clinical utility of NLR as part of a multi-parameter evaluation system rather than as an isolated biomarker. Addressing the critical need for early identification of high-risk patients while utilizing readily available clinical data. This approach successfully balances scientific innovation with practical clinical application.”

References

Shen C, Liu M, Cai Z, et al. Association between neutrophil-to-lymphocyte ratio and early renal function decline in patients with immunoglobulin a nephropathy. Annals of Medicine. 2025;57(1). https://doi.org/10.1080/07853890.2025.2559133

Wang S, Dong L, Pei G, et al. High Neutrophil-To-Lymphocyte Ratio Is an Independent Risk Factor for End Stage Renal Diseases in IgA Nephropathy. Frontiers in Immunology. 2021;12. https://doi.org/10.3389/fimmu.2021.700224