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

Abstract

ABSTRACT 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.