Blood cadmium may signal osteoporosis-related fractures among never-smokers

Increased concentrations of cadmium in the blood are associated with a heightened risk of developing osteoporosis-related fractures among individuals who have never smoked, according to a study.

For the study, researchers used data from the Swedish population-based Malmö Diet and Cancer study cohort. The population included 2,113 never-smoking participants who had incident cases of osteoporosis-related fractures and 2,113 age- and sex-matched controls who likewise had never smoked.

Blood samples were collected to measure the concentrations of cadmium. Blood cadmium measurements could be obtained in 2,103 and 2,105 participants in the case and control groups, respectively. Incident osteoporosis-related fractures at different sites (hip, distal radius, and proximal humerus) were ascertained using the National Patient Register.

Compared with the control group, the case group had higher blood cadmium levels (mean 0.26 vs 0.25 μg/L; p=0.04), lower body mass index (25.7 vs 26.1 kg/m²; p=0.0002), and lower haemoglobin concentration in blood (137.7 vs 138.4 g/L; p=0.02). Moreover, individuals in the case group were more likely to have previously been treated for a fracture (23.7 percent vs 18.8 percent; p=0.01).

Multivariable logistic regression analysis showed a significant positive association between blood cadmium and the risk of fracture (per μg/L of cadmium in blood: odds ratio [OR], 1.58, 95 percent confidence interval [CI], 1.08–2.31).

In analyses by cadmium quartiles, the highest vs lowest quartile was associated with increased fracture risk (>0.31 vs <0.15 μg/L: OR, 1.21, 95 percent CI, 1.01–1.45).