An association between copeptin (precursor molecule of arginine vasopressin) and markers for renal function has been reported, but data on the Japanese population has been limited. In this study, we investigated whether elevated copeptin levels are associated with microalbuminuria and renal dysfunction in the general Japanese population. A total of 1,262 participants (842 female and 420 male) were enrolled. Multiple regression analysis was performed to assess the association of copeptin levels (logarithm) with estimated glomerular filtration rate (eGFR) and the urine albumin-to-creatinine ratio (UACR) after adjusting for age, BMI, and lifestyle variables. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression methods in which chronic kidney disease (CKD) was the dependent variable. The copeptin levels differed significantly with sex, but were not found to be related to age or the span of time from preceding meal to blood sampling. In female participants, copeptin level was negatively correlated with eGFR (beta = -0.100, p-value = 0.006) and positively correlated with UACR (beta = 0.099, p-value = 0.003). In male participants, a negative correlation (beta = -0.140, p-value = 0.008) was observed for eGFR. In both females and males, those with high copeptin levels had more than double the ORs of CKD (OR = 2.1-2.9) adjusted for CKD-related factors. The present study found elevated copeptin levels to be associated with renal function loss in the Japanese population and microalbuminuria in female. Moreover, it was evident that high copeptin levels are associated with CKD. These results suggest that copeptin could be considered a marker of renal function.
Keywords: Chronic kidney disease; Copeptin; Epidemiology; Vasopressin.