Cadmium exposure and kidney stone formation in the general population--an analysis of the National Health and Nutrition Examination Survey III data

Background and Purpose: Cadmium exposure has been associated with a greater risk of kidney stone formation in occupational exposure studies, but data on such an association in the general population are scarce. Subjects and Methods: We assessed the National Health and Nutrition Examination Survey data from 1988 to 1994 in terms of the risk of stone formation. Persons reporting a history of kidney stones were defined as stone formers (n=749), and the association between a positive history of kidney stones and high environmental cadmium exposure levels (defined as urinary cadmium >1 μg/g) was analyzed by logistic regression analysis, stratifying by sex and adjusting for age, race/ethnicity, body mass index, smoking habits, region of residence, and daily intake of calcium and sodium. Results: The odds ratio of lithiasis associated with urinary cadmium >1 μg/g was 1.40 (95% confidence interval 1.06, 1.86) in females (P=0.019). The association between urinary cadmium and kidney stones was not significant in males. Conclusions: These findings suggest that moderately high levels of urinary cadmium are associated with a greater propensity for kidney stone formation in females in the general population.