Association Between Blood Selenium Levels and Stroke: A Study Based on the NHANES (2011-2018)

At present, the association between circulating selenium and stroke is still in dispute. Thus, this study aimed to ascertain the association with a larger sample size than the previous study, based on the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. In total, 13755 adults over the age of 20 years were included in our study. Multivariate logistic regression models were applied to analyze the correlation between blood selenium levels and stroke. The smooth curve fitting was performed to test the dose-response effects between blood selenium levels and stroke. After adjusting for all confounders, blood selenium levels were negatively associated with stroke (odds ratio [OR] = 0.57, 95% confidence interval [CI]: 0.37-0.87, P = 0.014). In the fully adjusted model, the highest tertile of blood selenium levels was negatively associated with stroke compared with the lowest tertile (OR = 0.70, 95% CI: 0.53-0.93, P for trend = 0.016). Moreover, the relationship between blood selenium levels and stroke was linear. In subgroup analyses, we observed that the test for interactions was significant for body mass index (BMI) and uric acid (P for interaction < 0.05). The negative relationship was stronger in participants with BMI 25-30 kg/m² (OR = 0.23, 95% CI: 0.13-0.44, P < 0.001). Therefore, in American adults, the relationship between blood selenium levels and stroke was negative, with a linear tendency. In the future, a cohort study is warranted to further confirm this relationship.