Association of Serum Creatinine, Urea, and Glomerular Filtration Rate with the Progression of Diabetic Associated Kidney Complications: A Retrospective Case-Control Study

Abstract

Introduction: Diabetes mellitus (DM) is a prevalent metabolic disorder frequently leading to serious renal complications, particularly diabetic nephropathy. This retrospective case–control study investigated the levels and associations of commonly used enzymatic (serum creatinine and urea) and physiological (glomerular filtration rate [GFR]) markers of kidney function in diabetic patients compared to non-diabetic controls. Methodology: A total of 237 participants were enrolled, comprising 81 diabetic cases and 156 non-diabetic controls. Creatinine and urea levels were determined using enzymatic methods, measuring optical density, whereas GFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, based on creatinine, age, and sex. Statistical comparisons include p-value, Pearson correlation, etc. Results: The diabetic group exhibited significantly higher mean levels of serum creatinine (2.08 ± 2.26 mg/dL) and urea (57.71 ± 38.75 mg/dL) and a significantly lower mean GFR (59.59 ± 34.16 mL/min/1.73 m2) compared to the non-diabetic control group (0.95 ± 0.69 mg/dL, 31.79 ± 20.49 mg/dL, and 96.72 ± 23.77 mL/min/1.73 m2, respectively; all comparisons with p < 0.005). Correlation analysis revealed a more scattered positive association between creatinine and urea, and a pronounced inverse correlation between GFR and both creatinine and urea in the diabetic cases, suggesting a compromised renal function profile. Conclusions: Our findings demonstrate a significant association between diabetes and impaired renal function, as evidenced by elevated creatinine and urea levels and reduced GFR. These readily available biomarkers are crucial prognostic indicators for the early detection and effective management of diabetic nephropathy, emphasizing the importance of rigorous metabolic and blood pressure control to mitigate disease progression.