AN INSIGHTFUL systematic review and meta-analysis suggests that the neutrophil-to-lymphocyte ratio (NLR) may serve as a useful inflammatory biomarker for identifying patients at increased risk of diabetic nephropathy (DN) and its progression.
DN is one of the most serious complications of diabetes and a leading cause of chronic kidney disease and end-stage renal failure worldwide. Early identification of patients at risk remains challenging, driving interest in simple, cost-effective biomarkers that can support risk stratification. NLR, derived from routine blood counts, reflects systemic inflammation and has gained attention in a range of chronic diseases.
In this comprehensive analysis, researchers reviewed 39 cohort and case–control studies involving 14,300 participants, assessing the association between NLR and DN occurrence, disease progression, and mortality. Studies published up to May 28, 2025 were included, and the review was prospectively registered in PROSPERO.
Link Between Elevated NLR and Diabetic Nephropathy Risk
The findings demonstrated a strong association between elevated NLR and the presence of diabetic nephropathy. Patients with DN had significantly higher NLR levels than diabetic controls without nephropathy, with pooled analyses showing more than a twofold increased odd of DN occurrence. This association remained robust across multiple analytical approaches.
Among patients already diagnosed with DN, higher NLR values were also linked to worsening kidney function. Individuals who experienced renal deterioration showed significantly elevated NLR compared with those whose kidney function remained stable, indicating that NLR may have prognostic value for disease progression.
The association between NLR and mortality in DN patients was less clear. Although a trend toward increased mortality risk was observed with higher NLR, the pooled result did not reach statistical significance. Subgroup analyses suggested that the predictive value of NLR was stronger in patients aged 60 years or older and in those with a body mass index of at least 25 kg/m².
Clinical Implications of NLR in Diabetic Nephropathy
Despite the promising findings, the authors cautioned that substantial heterogeneity and possible publication bias were present across studies. Differences in study design, patient populations, and NLR cut-off values may have influenced results.
Overall, the study supports NLR as a potentially valuable, accessible biomarker for identifying patients at higher risk of DN onset and progression. The authors emphasised the need for large, well-designed prospective studies to standardise measurement and confirm its clinical utility.
Reference
Liu H et al. The predictive value of neutrophil-to-lymphocyte ratio for the occurrence, progression, and mortality of diabetic nephropathy: a systematic review and meta-analysis. Sci Rep. 2026.doi: 10.1038/s41598-025-30680-4.
