Association between blood cadmium levels and the risk of chronic kidney disease in Korea, based on the Korea National Health and Nutrition Examination Survey 2016-2017

Background: Exposure to environmental cadmium can have harmful effects on the human kidneys. The relationship between the degree of exposure to cadmium and the risk of chronic kidney disease (CKD) in the general population is unclear. Objectives: To investigate the association between blood cadmium levels and CKD risk using samples from the Korea National Health and Nutrition Examination Survey (KNHANES) VII data, which included heavy metal and serum creatinine levels. Methods: We analyzed the data of 4,222 adults from January 1, 2016, to December 31, 2017. Multiple logistic regression analysis was conducted on weighted data using complex sampling to assess the relationship between blood cadmium levels and CKD. We performed a stratified analysis in the presence of comorbidities such as diabetes or hypertension. Results: There was a positive association between blood cadmium level and the risk of CKD in hypertensive or nondiabetic participants after adjustment, but not between blood cadmium level and CKD in normotensive or diabetic participants. The corresponding odds ratios (OR) of cadmium for CKD were 2.70 (95% confidence interval [CI], 1.49-4.90, P = 0.001) in samples with hypertension and 2.40 (95% CI, 1.56-3.70, P < 0.001) in samples without diabetes. Conclusions: Our findings suggest an association between blood cadmium level and the risk of CKD in hypertensive or nondiabetic participants. Additional research is necessary to elucidate the relationship between cadmium exposure and CKD risk, particularly in individuals with comorbidities.