RESUMO
AIM: Malnutrition has been linked to cardiovascular diseases. Both selenium and iron deficiency have been associated with worse prognosis in patients with heart failure (HF). Yet, little is known about the role of micronutrients in the development of atrial fibrillation (AFib). In this study, we aimed to elucidate the association of micronutrient deficiencies with new-onset AFib. METHODS: Selenium, magnesium, and iron parameters were measured in a well-characterized prospective cohort study (N = 5452). Selenium deficiency was defined as serum selenium < 70 µg/L, iron deficiency as serum ferritin < 30 µg/L, and magnesium deficiency as plasma magnesium < 0.85 mmol/L. New-onset AFib was the primary outcome. Additionally, we tested for previously reported effect-modifiers where applicable. RESULTS: Selenium, iron, and magnesium deficiency was observed in 1155 (21.2%), 797 (14.6%), and 3600 (66.0%) participants, respectively. During a mean follow-up of 6.2 years, 136 (2.5%) participants developed new-onset AFib. Smoking status significantly interacted with selenium deficiency on outcome (p = 0.079). After multivariable adjustment for components of the CHARGE-AF model, selenium deficiency was associated with new-onset AFib in non-smokers (HR 1.69, 95% CI 1.09-2.64, p = 0.020), but not in smokers (HR 0.78, 95% CI 0.29-2.08, p = 0.619). Magnesium deficiency (HR 1.40, 95% CI 0.93-2.10, p = 0.110) and iron deficiency (HR 0.62, 95% CI 0.25-1.54, p = 0.307) were not significantly associated with new-onset AFib. CONCLUSION: Selenium deficiency was associated with new-onset AFib in non-smoking participants. Interventional studies that investigate the effects of optimizing micronutrients status in a population at risk are needed to assess causality, especially in those with selenium deficiency. Micronutrients deficiencies (selenium, iron, and magnesium) have been associated with cardiovascular diseases and mitochondrial dysfunction in human cardiomyocytes. However, it is not known whether these deficiencies are associated with atrial fibrillation. To investigate this question, we measured all three micronutrients in 5452 apparently healthy individuals. After a mean follow-up of 6.2 years, there were 136 participants who developed atrial fibrillation. Participants with selenium deficiency had a significant increased risk to develop atrial fibrillation, as did the participants with two or more deficiencies.
RESUMO
AIM: To elucidate the relationship between serum selenium levels and the risk of mortality and new-onset heart failure (HF) 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 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 female. Median follow-up was 8.4 years. Selenium levels associated positively with female sex, higher total cholesterol and glucose concentrations, and associated negatively with incidence of anaemia, iron deficiency, current smoking, increased 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] 0.87-1.06, 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 0.79-0.96, p = 0.005), lower risk of new-onset HF (HR 0.82, 95% CI 0.69-0.96, p = 0.017), as well as reduced risk of the composite endpoint (HR 0.86, 95% CI 0.79-0.94, 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.