The Neutrophil‐To‐Lymphocyte Ratio as an Associated Biomarker of Diabetic Nephropathy in Type 2 Diabetes Mellitus

BACKGROUND AND OBJECTIVE: Chronic low-grade inflammation drives the development and progression of type 2 diabetes mellitus (T2DM) and microvascular complications, including diabetic kidney disease. The neutrophil-to-lymphocyte ratio (NLR) is a routine hematological index reflecting systemic inflammatory activity. This study evaluated NLR's association with T2DM, glycemic control, and renal function in a Hodeidah City cohort, assessing renal function via the CKD-EPI creatinine equation. METHODS: Continuous variables were expressed as medians (interquartile ranges) and analyzed using nonparametric tests. Associations were evaluated via Spearman correlation and exploratory linear regression. RESULTS: Primary comparisons revealed that T2DM patients possessed a significantly higher NLR than healthy controls, confirming a systemic inflammatory phenotype. Within the T2DM group, NLR did not differ significantly across HbA1c (p = 0.066) or eGFR categories (p = 0.328). However, NLR positively correlated with serum creatinine (Spearman ρ = 0.352, p = 0.022) and demonstrated an inverse, nonsignificant association with eGFR (ρ = -0.275, p = 0.078). CONCLUSIONS: NLR may serve as a practical adjunctive inflammatory biomarker in T2DM. Nevertheless, accurate clinical interpretation requires careful adjustment for renal function, comorbidities, and medication exposure. The absence of comprehensive data regarding the albumin-to-creatinine ratio (ACR), diabetes duration, and specific medication history limited multivariable confounder adjustment and complete nephropathy staging.