Gender difference in blood cadmium concentration in the general population: Can it be explained by iron deficiency?

Introduction: Gender differences in blood cadmium concentrations and the effect of iron deficiency on blood cadmium levels were analyzed in a representative sample of Koreans assessed in the Korean National Health and Nutritional Examination Survey (KNHANES) 2008-2011. Methods: A rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0. μg/L), low normal (15.0-<30.0. μg/L for females and 15.0-<50.0. μg/L for males), and normal (≥30.0. μg/L for females and ≥50.0. μg/L for males), and its association with blood cadmium levels was assessed after adjustment for various demographic and lifestyle factors. Results: The geometric mean (GM) of the blood cadmium level was significantly higher in females than in males, and significantly higher in older individuals for both genders. After controlling for covariates, multiple regression analysis with interaction terms showed that blood cadmium was correlated with serum ferritin levels only in pre-menopausal females. Discussion: Iron deficiency is associated with blood cadmium levels in a representative sample of pre-menopausal females, as evaluated in KNHANES. Gender differences in blood cadmium concentration may not be due solely to an iron deficiency-associated increase in blood cadmium.