AIM: To elucidate the relationship between serum selenium levels and the risk of mortality and new onset heart failure in the general adult population.
METHODS AND RESULTS: Selenium was measured in a Dutch cohort and a retrospective analysis of prospectively assessed data was performed. Main outcome measures were all-cause mortality and incidence of new-onset heart failure (HF) separately, and combined as a composite endpoint. Serum selenium was measured in 5973 subjects and mean selenium concentration was 84.6 (±19.5) μg/L. Mean age was 53.6 (±12.1) years and 3103 subjects (52%) were females. Median follow-up period was 8.4 years. Selenium levels associated positively with female sex, higher total cholesterol and glucose concentrations, and associated negatively with incidence of anemia, iron deficiency, current smoking, increasing C-reactive protein levels, and higher body mass index. Univariate analysis on all subjects showed no association of continuous selenium concentrations, per 10 μg/L increase, with the composite endpoint (Hazard Ratio [HR]=0.96, 95% Confidence interval [CI]: 0.87 to 1.06, p = 0.407). However, significant interaction with smoking status was observed. In non-smoking subjects (N=4288), continuous selenium concentrations were independently associated with reduced mortality risk (HR=0.87, 95% CI: 0.79 to 0.96, p = 0.005), lower risk of new-onset HF (HR=0.82, 95% CI: 0.69 to 0.96, p = 0.017), as well as reduced risk of the composite endpoint (HR= 0.86, 95% CI: 0.79 to 0.94, p = 0.001). In smoking subjects, no associations were found.
CONCLUSION: Serum selenium was independently associated with multiple indicators of the metabolic syndrome. In addition, high selenium levels were independently associated with reduced mortality and new-onset HF in non-smokers. Well-powered interventional studies are necessary to evaluate the potential benefit of repleting selenium, especially in non-smoking subjects.