Selenium Concentration in Korean Patients with Thyroid Disease: a Preliminary Report

BACKGROUND AND OBJECTIVES: Selenium is an important trace element for thyroid hormone metabolism, and its deficiency can cause hypothyroidism. Serum selenium concentration is the best biomarker to reflect selenium intake and reserve, although other markers can reflect. Therefore, we preliminarily assessed serum and urine selenium concentrations in patients with thyroid disease compared to those of a healthy population. We also investigated the correlation between serum and urine selenium concentration, thyroid hormone and urinary iodine concentration (UIC). MATERIALS AND METHODS: A total of 97 patients (32 men, 65 women, 52.4±14.7 years) with benign thyroid nodules or thyroid dysfunction who visited the Samsung Medical Center between 2008 and 2013 were included. Data for 175 healthy subjects provided by Lee et al. were used as the control. Serum T3, free T4, and thyroid stimulating hormone (TSH) were measured using commercialized RIA or IRMA kits. Serum/urine selenium and UIC were measured by inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS: Median serum selenium concentration was 110 µg/L (95% CI, 73-156). Median urine selenium concentration was 66.3 µg/gCr (95% CI, 28.7-283.5). Compared to 175 healthy subjects (serum 84 µg/L [95% CI, 30-144], urine 34.5 µg/gCr [95% CI, 0.8-107.2]), serum and urine selenium concentrations of patients with thyroid disease were significantly higher than those of healthy subjects (p<0.001). Serum selenium concentration was significantly correlated with urine selenium concentration after log transformation (r=0.88, p=0.022), but was not significantly correlated with UIC, T3, free T4 and TSH. CONCLUSION: Selenium concentrations of patients with thyroid disease were significantly higher than those of healthy subjects. Serum selenium concentration was significantly correlated with urine selenium concentration.

Selenium Concentration in Korean Patients with Thyroid Disease: a Preliminary Report

BACKGROUND AND OBJECTIVES: Selenium is an important trace element for thyroid hormone metabolism, and its deficiency can cause hypothyroidism. Serum selenium concentration is the best biomarker to reflect selenium intake and reserve, although other markers can reflect. Therefore, we preliminarily assessed serum and urine selenium concentrations in patients with thyroid disease compared to those of a healthy population. We also investigated the correlation between serum and urine selenium concentration, thyroid hormone and urinary iodine concentration (UIC). MATERIALS AND METHODS: A total of 97 patients (32 men, 65 women, 52.4±14.7 years) with benign thyroid nodules or thyroid dysfunction who visited the Samsung Medical Center between 2008 and 2013 were included. Data for 175 healthy subjects provided by Lee et al. were used as the control. Serum T3, free T4, and thyroid stimulating hormone (TSH) were measured using commercialized RIA or IRMA kits. Serum/urine selenium and UIC were measured by inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS: Median serum selenium concentration was 110 µg/L (95% CI, 73-156). Median urine selenium concentration was 66.3 µg/gCr (95% CI, 28.7-283.5). Compared to 175 healthy subjects (serum 84 µg/L [95% CI, 30-144], urine 34.5 µg/gCr [95% CI, 0.8-107.2]), serum and urine selenium concentrations of patients with thyroid disease were significantly higher than those of healthy subjects (p<0.001). Serum selenium concentration was significantly correlated with urine selenium concentration after log transformation (r=0.88, p=0.022), but was not significantly correlated with UIC, T3, free T4 and TSH. CONCLUSION: Selenium concentrations of patients with thyroid disease were significantly higher than those of healthy subjects. Serum selenium concentration was significantly correlated with urine selenium concentration.

Comparative study of the average level of serum selenium in adult mongolians by geographic regions / Монголын Анагаах Ухаан

Background: Disorders in the human body due to selenium defi ciency are associated with geographiclocation or environment, especially selenium concentrations in water and in soil. Selenium concentrationsin the blood of populations around the world, varies greatly. To date, no research has been conducted onaverage serum selenium level of adult Mongolians.Goal. To conduct a comparative study on the average serum selenium level of adult Mongolians bygeographic regions.Materials and Methods. In this study were participated 2339 healthy subjects randomly selectedfrom sampling units based on 4 geographical regions of Mongolia. For the study were used thequestionnaire and biochemical methods. Blood samples were collected from all subjects and serumselenium concentration was measured by the thermo fi sher scientifi c analyzer using atomic absorptionspectrophotometer method.Result: The mean serum selenium level in adult Mongolians was 0.78 μmol/l. A comparative analysisshowed a statistically signifi cant difference (ð<0.0001) in the mean serum selenium level of adultMongolians living in different geographic regions. In particular, the mean serum selenium level ofadult Mongolians was 0.85 μmol/l in the Altai Mountain, 0.57 μmol/l in Khangai mountain, 1.0 μmol/l inGobi, 0.71 μmol/l in Dornod steppe regions and thus indicator was 0.75 μmol/l among adult citizens ofUlaanbaatar. Majority of residents living in Khangai mountain and Dornod steppe regions were at a riskof selenium defi ciency.Conclusions:1. Comparative analysis of the average serum selenium level of adult Mongolians by region showedthat the Gobi region has highest (1.0 μìîë/ë) and Khangai region has the lowest (0.57 μìîë/ë).2. Study fi ndings showed that 7 – 8 individuals out of 10 residents of Dornod steppe and Khangairegions were at the risk of selenium defi ciency.

Iron Status According to Serum Selenium Concentration and Physique in Young Female Adults

Se and Fe are trace minerals acting as antioxidant scavenging free radicals. Iron deficiency is the most frequently reported nutritional deficiency in females. Body iron status are known to be dependent not only upon dietary iron intake, but also upon micro-mineral nutrition and obesity. Antioxidants such as selenium are reported to play an important role on the regulation of erythropoiesis by protecting RBC membrane from antioxidative damage. In this study, iron status in young females and its relationships with selenium status and physique were examined. Serum selenium and iron concentrations were measured by HANARO research reactor using neutron activation analysis method (NAA-method). The proportion with iron deficiency and anemia were 27.1% and 8.6%, respectively in young females, but the proportion with iron deficient anemia was 1.4%. The mean serum selenium level was 12.0 microgram/dL and in normal range in the young women. The study participants were tertiled according to BMI and serum selenium levels. Serum ferritin and iron levels inclined with increasing BMI tertiles. Serum iron and RBC count were higher in middle selenium group than low selenium group. Individuals had significantly lower hematocrit level in the lowest tertile for their serum selenium levels compared with the highest tertile. The serum ferritin level was predicted 25% by BMI and RBC count 26.2% by the serum selenium level and body fat%. In conclusion, this study shows that body iron status in young adult females are influenced by obesity and body selenium status.