Race and Gender Differences in the Associations Between Cadmium Exposure and Bone Mineral Density in US Adults

Several previous studies have found the deleterious effects of cadmium exposure on bone. However, studies on the effects of cadmium exposure on bone mineral density (BMD) in gender- and race-specific groups are still lacking. The aim of this study was to investigate the relationship between cadmium exposure and BMD in adults and the gender and racial differences therein. Weighted multivariate regression, generalized weighted model, and smoothed curve fitting were used to explore the relationship between lumbar BMD with blood cadmium (B-Cd) and urine cadmium (U-Cd) based on data from the National Health and Nutrition Examination Survey (NHANES). In addition, subgroup analyses were further used to investigate the differential associations across gender and race. Of the 4335 adult participants. After adjusting for primary demographic variables, B-Cd [- 0.018 (- 0.028, - 0.008)] and U-Cd [- 0.010 (- 0.020, - 0.001)] were shown to be negatively related to lumbar BMD. In the fully adjusted model, the negative association between B-Cd and lumbar BMD was maintained [- 0.010 (- 0.018, - 0.002)]. In the subgroup analysis stratified by gender and race, this relationship was retained in females and non-Hispanic blacks. Furthermore, these negative associations were most pronounced among non-Hispanic black women [B-Cd and lumbar BMD, - 0.046 (- 0.076, - 0.017); U-Cd and lumbar BMD, -0.034 (- 0.063, - 0.006)]. Our findings suggest that there are significant sex and race differences in the negative association between cadmium exposure and BMD. This negative association was most prominent in non-Hispanic black females.