Abstract

Background: Diabetic kidney disease (DKD) is one of the most prevalent and severe microvascular complications of type 2 diabetes (T2DM). Since most DKD patients are diagnosed at advanced stages with significant renal damage, identifying novel biomarkers for early-stage DKD assessment is critical for timely intervention. The white blood cell-to-hemoglobin ratio (WHR) is a novel and integrated index that reflects both inflammation and anemia, both of which have been implicated in DKD progression. However, the association between WHR and DKD remains unexplored. This study aims to elucidate the relationship between complete blood cell (CBC) indices and DKD pathogenesis, and evaluate the potential of WHR as a predictive biomarker for DKD progression.

Methods: A total of 6257 T2DM patients, including 1721 patients with DKD and 4536 patients without DKD, were enrolled in this cross-sectional study. Basic information, body measurements and clinical parameters, including metabolic parameters, CBC indices and indicators of renal impairment, were collected and compared between groups. Spearman’s correlation and univariate/multivariate logistic regression analysis were performed to assess the correlation  between CBC indices and indicators of renal impairment, as well as the relationship between WHR and DKD occurrence. Receiver operating characteristic (ROC) analysis was used to calculate the discriminatory performance of WHR for DKD presence.

Results: Age, male predominance, T2DM duration, insulin usage, blood pressure, fasting blood glucose and triglycerides were greater in DKD patients with  than non-DKD patients (P < 0.05). Notably, the DKD patients also more likely exhibited lower hemoglobin (Hb) levels and higher inflammatory CBC indices (P < 0.001). Among all the inflammatory indices, WHR showed the strongest association with DKD occurrence and positively correlated with multiple renal impairment indicators. After adjusted for confounding factors (age, gender, BMI, duration of T2DM, HbA1c, SBP, DBP and UACR), WHR remained independently associated with DKD progression [odds ratio (OR):3.669, 95% confifidence interval (CI): 2.407-5.592, P<0,001]. Moreover, ROC analysis identified WHR as a risk factor for DKD, particularly in T2DM patients aged>40, with a cut-off value of 0.529 (area under the curve = 0.641, P<0.001). 

Conclusion: WHR was significantly associated with an increased risk of DKD, suggesting its potential as a diagnostic and management indicator for DKD.