Role of urinary trace elements in diabetic kidney disease: a cross-sectional analysis

IntroductionThe balance of trace elements plays an important role in diabetic kidney disease (DKD) patients. However, studies on the differences in urinary trace elements across different DKD stages are scarce. This study aimed to explore the associations between nine essential trace elements and DKD.Research design and methodsThis cross-sectional analysis included 830 diabetic patients. Participants were classified into non-DKD (NDKD) and DKD, the latter was further grouped into mid and end DKD based on estimated glomerular filtration rate (eGFR), and the case and control were matched based on age and sex. The concentration of urinary trace elements was measured with inductively coupled plasma mass spectrometry.ResultsUrinary concentrations of copper (Cu) and manganese (Mn) in DKD patients were significantly higher than that of NDKD patients, whereas that of iron (Fe), cobalt, selenium, and nickel (Ni) of DKD were lower. Positive correlations between urinary Mn/Cu and the risk of mid-stage and end-stage DKD were revealed by conditional logistic regression, while Fe and Ni were negatively associated with the risk of DKD. In mixed effect analyses, no significant trend was found for joint trace element exposure and risk of mid DKD, while negative associations between combined effects of trace elements and the risk of end DKD were observed.ConclusionsThis study revealed different associations between trace elements and the risk of mid and end DKD using both single and mixture effect modeling. The results suggested that the urinary trace element profile might be associated with the progression of DKD, which provides important insights for understanding the pathogenesis of DKD and developing individualized nutritive management strategies.