URINARY BIOMARKERS IN DIABETIC NEPHROPATHY: CORRELATION BETWEEN UREA AND CREATININE LEVELS

Abstract

Diabetic nephropathy (DN) is one of the most common complications that can result in chronic kidney disease and end-stage kidney failure all over the world and it remains very important to identify DN at the early stages. This study aimed to assess the connection of urinary urea, urinary creatinine and urinary urea-to-creatinine ratio (UCR) in diabetic nephropathy patients with the healthy controls as well as its role as a biomarker in renal impairment. Two hundred subjects were recruited, 100 of which were patients diagnosed with DN and 100 healthy control subjects. Demographic and clinical factors such as age, gender, body mass index (BMI), blood pressure and glycated hemoglobin (HbA1c) were noted down. Serum and urinary urea and creatinine concentrations were determined and UCR calculated. Patients with DN had significantly higher BMI, systolic and diastolic blood pressure, HbA1c, serum urea, serum creatinine, and UCR when compared to controls (p < 0.001). Pearson correlation analysis indicated a strong positive association between urinary urea and creatinine in DN patients (r=0.74, p<0.001) and the correlation was moderate with control group (r=0.52, p<0.001). On Multivariate logistic regression, urinary urea, urinary creatinine, UCR and HbA1c are independent predictors of DN after adjusting for confounding factors (p < 0.01). Although urinary urea and creatinine showed a positive correlation with each other, logistic regression indicated that higher urinary urea and UCR are associated with DN whereas lower urinary creatinine was associated with disease severity. These results confirm the use of urinary biomarkers as valuable tests of the presence of diabetic nephropathy. The combination of urinary urea and UCR tests with the customary clinical radiological and biochemical tests may help to detect renal dysfunction among diabetics earlier. Therefore, early disease identification and early intervention can delay disease progression, achieve better patient outcomes and prevent the health care long-term burden of diabetic kidney disease.