Serum Biomarker for Cardiovascular Disease Risk Assessment in Patients With Diabetic Nephropathy

The objective of this study was to compare serum sirtuin 1 level in diabetic nephropathy patients with or without coronary artery disease. Methods: In this cross-sectional study, 108 diabetic nephropathy patients were included, among which 54 were diagnosed with coronary artery disease based on coronary angioplasty, lipid profile, drug details, and case history, while 54 were without coronary artery disease. Patients above 18 years with nephropathy, as per spot microalbuminuria test, were included. The study excluded patients with any malignancies. Ethical approval was obtained, and consent was acquired from each participant. Serum was obtained from 2ml of whole blood and stored at -20°C before measuring serum sirtuin 1 level using Enzyme Linked Immunosorbent Assay (ELISA).

The mean serum sirtuin 1 level was 2.27 ng/ml (2.033, 2.185) in diabetic nephropathy patients with coronary artery disease and 2.55 ng/ml (2.069, 2.372) in those without. Although diabetic nephropathy patients had higher serum sirtuin 1 levels, the difference was not statistically significant (p = 0.063). The ROC curve analysis yielded a cut-off value of 2.30 ng/ml, with an AUC of 0.604, indicating sirtuin 1 level may not be a robust biomarker for predicting coronary artery disease in diabetic nephropathy patients. Furthermore, no significant association was found between serum sirtuin 1 levels and microalbuminuria stages in DN patients with CAD (p = 0.705).

In conclusion, serum sirtuin 1 levels showed no significant difference between diabetic nephropathy patients with and without coronary artery disease. The analysis suggests that serum sirtuin 1 level may not strongly indicate the presence or severity of coronary artery disease in diabetic nephropathy patients.