Findings from a recent study suggest that cadmium exposure may be an independent risk factor for ischemic stroke in the US general population. However, never smoking and maintaining a high serum zinc level may ameliorate the potential adverse effects of cadmium exposure. A case-cohort study was designed nested in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, including 680 adjudicated incident cases of ischemic stroke and 2,540 participants in a randomly selected subcohort. Urinary creatinine-corrected cadmium concentration was measured at baseline. Researchers found:

• The median urinary cadmium concentration was 0.42 μg/g creatinine.
• After adjustment for potential confounders, urinary cadmium was associated with increased incidence of ischemic stroke (quintile 5 vs quintile 1: HR 1.50).
• The observed association was more pronounced among participants in the lowest serum zinc tertile (tertile 3 vs tertile 1: HR 1.82) but was attenuated and became nonsignificant among never smokers (tertile 3 vs tertile 1: never smokers: HR 1.27; ever smokers: HR 1.60).