Cross-sectional Study: Relationship Between Serum Selenium and Hypertension in the Shandong Province of China.

Although selenium, which is a necessary trace element for the human body, has been considered to be beneficial to the cardiovascular system and helpful to lower blood pressure, more and more evidence shows that high amounts of selenium are a risk factor for hypertension. A random multistage sampling which included the cluster method was performed; a total of 9076 urban and rural residents between 18 and 80 years old in the Shandong province of China were investigated by questionnaire, physical examination, and laboratory tests. The prevalence of hypertension was 42.1% in males and 35.3% in females. The mean (standard deviation) selenium concentration was 124.68 (36.32) µg/l in males and 119.54 (31.88) µg/l in females. After adjusting for potential confounders, logistic regression analysis showed that the highest selenium levels were associated with a risk of hypertension (OR = 1.192; 95% CI 1.009-1.407) in females, while there was no significant difference in males (OR = 1.043; 95% CI 0.864-1.259). Our findings suggest that high selenium levels in females are more likely to increase the risk of hypertension compared to similar levels in males. More attention should be paid to the metabolic mechanisms and physiological effects of selenium in females.

Relationship between higher serum selenium level and adverse blood lipid profile.

BACKGROUND: As the key component of glutathione peroxidase with unique antioxidant properties, selenium has been considered to play an important part on lipid metabolism. However, the associations of serum selenium concentrations with lipid concentrations and dyslipidemia are still controversial. METHODS: We analyzed cross-sectional data including serum selenium levels, lipid concentrations and other related indexes of 8198 rural Chinese. Serum selenium was measured by inductively coupled plasma mass spectrometry, and total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-c) and low density lipoprotein-cholesterol (LDL-c) of serum were measured with kits. RESULTS: Overall, mean serum selenium was 120 µg/l. Multivariate liner regression revealed that selenium concentrations were positively correlated with TC (P < 0.001), HDL-c (P < 0.001), TG (P < 0.001) and LDL-c (P < 0.001). Compared with the lowest quintile of serum selenium, participants in quintile 3, 4 and 5 had higher risks of High-TC dyslipidemia (P ≤ 0.02) and High-LDLC dyslipidemia (P < 0.02) after adjusting for covariates. In the stratified analyses, we found that the selenium-dyslipidemia associations were significantly stronger in post-menopausal women (OR: 2.72; 95% CI: 1.97, 4.17) and diabetics (OR: 9.40; 95% CI: 3.02, 29.26). CONCLUSION: Elevated serum selenium levels were correlated with the increased concentrations of TC, LDL-c, HDL-c and TG, and increased the risk of High-TC and High-LDLC dyslipidemia among rural Chinese. However, the real associations between serum selenium and lipid profile should be verified in specifically designed randomized trials in future.

Association of Elements with Schizophrenia and Intervention of Selenium Supplements.

The purpose of this study is to explore more trace elements (zinc, potassium, copper, iron, boron, manganese, selenium, chromium and cadmium elements) in addition to calcium, magnesium, lead and arsenic in the sera of patients with schizophrenia and the general population in China and to determine the effect of selenium on schizophrenia patients. Participants were collected from the Pingyin County Mental Health Hospital and Pingyin County. A t test was used to analyse the differences between schizophrenia patients and healthy subjects, and element content differences in gender. Logistic multivariate regression analysis was applied to analyse the influence of elements to schizophrenia. Repeated measures analysis of variance was used to analyse differences in the elements after 1 and 3 months. Mn, Se, Cd, Pb, Ca, Cu and Fe were lower than those in the normal group, and B, Cr, As, K and Mg were higher than those in the control group. The odd ratios (ORs) of serum As and serum K were 2.624 and 1.035, respectively. The ORs of sera Cr, Mn, Se, Ca and Cu were all below one. After intervention of 'selenium weikang' about 1 and 3 months, the serum As was decreased and the serum selenium and copper were increased. Cr, Mn, Se, Ca and Cu might have beneficial, statistically significant effects on schizophrenia. Elements As and K might be harmful to schizophrenia with statistical significance. After selenium supplementation, the schizophrenia patients improved in some factors, like the appetite and memory, and the As element decreased.

High serum selenium levels are associated with impaired fasting glucose and elevated fasting serum glucose in Linyi, China.

BACKGROUND: The relationship between selenium level and impaired fasting glucose or elevated fasting serum glucose remains controversial. This study aimed to evaluate these associations in China. METHODS: This observational population study adopted a cluster sampling approach to enroll participants. Baseline information on selenium categories was tested using one-way analysis of variance and Kruskal-Wallis equality-of-populations rank tests. Multivariable logistic regression was used to investigate the association between serum selenium level and impaired fasting glucose or elevated fasting serum glucose. RESULTS: The mean serum selenium concentration was 121.5µg/L which in a relatively high baseline Se status. Differences were observed among individuals with normal, impaired fasting glucose and elevated fasting serum glucose levels in their basic information, physical examination results and laboratory findings. After adjusting for their basic information, physical examination results and laboratory findings, compared with the low-selenium group, the high-selenium groups (124.9-143.9 and above 143.9µg/L) had ORs for elevated fasting serum glucose of 2.31 (1.37-3.90) and 2.67 (1.59-4.48), respectively (both P<0.05). A sex-difference was observed, and a significant association between selenium levels and impaired fasting glucose was observed for males but not for females. CONCLUSIONS: The findings of this observational study suggest that relatively high selenium levels might be positively associated with elevated fasting serum glucose and relatively high selenium levels might be positively associated with impaired fasting glucose in men.