Relation of Copeptin with Diabetic and Renal Function Markers Among Patients with Diabetes Mellitus Progressing Towards Diabetic Nephropathy

Background: Arginine vasopressin (AVP) plays an important role in the pathophysiology of Diabetes Mellitus (DM) and its related complications like diabetic nephropathy. Copeptin is considered as a reliable surrogate biomarker of AVP. If raised levels of copeptin in diabetic patients are detected earlier, prognosis of DM can be improved by timely modulating the treatment strategy. Aims of the study: The study is therefore planned to assess copeptin levels in different groups of DM and in healthy controls to suggest a better and reliable biomarker for progressive stages of DM. Methods: Subjects were recruited as controls, pre diabetes, DM without nephropathy and diabetic nephropathy. Serum copeptin levels were measured by ELISA. While, Blood Urea Nitrogen (BUN), creatinine, Glycosylated Hemoglobin (HbA1c) and spot urinary albumin creatinine ratio (UACR) were done using spectrophotometry. Statistical analysis was done using ANOVA and Pearson's correlation tests on SPSS. Results: The average copeptin levels were 215.096 pg/mL. Copeptin levels were significantly elevated in subjects with positive family history of DM (p = 0.025), levels were also raised in pre diabetes kpatients (252.85 pg/mL) as compared to other groups. Copeptin levels were also correlated with HbA1c r = 0.171 (p = 0.101), BUN r = 0.244 (p = 0.007), creatinine r = 0.215 (p = 0.018), UACR r = 0.375 (p = <0.001) and GFR r = 0.215 (p = <0.019). Conclusion: The significant correlation of copeptin with diabetic and renal biomarkers, along with its positive association with family history of DM support its’ role as an early and reliable biomarker of DM and its associated nephropathy.