Association between serum selenium level and the prevalence of diabetes mellitus in U.S. population.

OBJECTIVE: Selenium seems to be a risk factor for diabetes mellitus (DM) in recent studies, opposite to the previous expectation that it may contribute to prevent DM. The authors aimed to ascertain the relationship between selenium and DM. METHODS: Data were collected from the National Health and Nutrition Examination Survey conducted from 2011 to 2014. A multivariate logistic regression analysis with adjustment for age, sex, race/ethnicity, hypertension, dyslipidemia and body mass index was conducted to evaluate the odds ratio for DM. RESULTS: The total number of subjects was 19,931. Large proportion of subjects were excluded due to young age (< 20 years) and missing data. The data of 3406 participants were analyzed, and a total of 604 had DM. In a multivariate logistic regression model, the increase of 10 µg/L in selenium increased the prevalence of DM by 12% (OR: 1.12; 95% CI: 1.06-1.18). Further analysis with 1:1 propensity score matching data with age and sex showed a similar results (OR: 1.08; 95% CI: 1.01-1.15). In addition, the restricted cubic spline regression showed a dose-dependent relationship between selenium level and DM. Subgroup analysis showed a dose-dependent relationship between selenium level and DM regardless of sex or race/ethnicity CONCLUSIONS: This large population study clearly demonstrates a positive association between selenium level and DM. This finding could have implications for nutritional supplementation in clinical settings.

Association between Serum Selenium Level and the Presence of Diabetes Mellitus: A Meta-Analysis of Observational Studies.

BACKGROUND: Epidemiological studies have suggested an association between selenium (Se) and diabetes mellitus (DM). However, different studies have reported conflicting results. Therefore, we performed a comprehensive meta-analysis to clarify the impact of Se on DM. METHODS: We searched the PubMed database for studies on the association between Se and DM from inception to June 2018. RESULTS: Twenty articles evaluating 47,930 participants were included in the analysis. The meta-analysis found that high levels of Se were significantly associated with the presence of DM (pooled odds ratios [ORs], 1.88; 95% confidence interval [CI], 1.44 to 2.45). However, significant heterogeneity was found (I²=82%). Subgroup analyses were performed based on the Se measurement methods used in each study. A significant association was found between high Se levels and the presence of DM in the studies that used blood (OR, 2.17; 95% CI, 1.60 to 2.93; I²=77%), diet (OR, 1.61; 95% CI, 1.10 to 2.36; I²=0%), and urine (OR, 1.49; 95% CI, 1.02 to 2.17; I²=0%) as samples to estimate Se levels, but not in studies on nails (OR, 1.24; 95% CI, 0.52 to 2.98; I²=91%). Because of significant heterogeneity in the studies with blood, we conducted a sensitivity analysis and tested the publication bias. The results were consistent after adjustment based on the sensitivity analysis as well as the trim and fill analysis for publication bias. CONCLUSION: This meta-analysis demonstrates that high levels of Se are associated with the presence of DM. Further prospective and randomized controlled trials are warranted to elucidate the link better.