Effect of oral iodized oil on thyroid size and thyroid hormone metabolism in children with concurrent selenium and iodine deficiency

Abstract

Objectives: To determine the ef®cacy of oral iodized oil in goitrous children who are both selenium (Se) and iodine de®cient; to investigate if Se status modi®es the response of iodine de®cient, goitrous children to oral supplementation with iodized oil. Design: A longitudinal intervention trial. Setting: Two rural villages in the western Co Ãte d'Ivoire. Subjects: 51 goitrous non-anemic schoolchildren with both iodine and Se de®ciency. Intervention: Each child received an oral dose of 0.4 ml iodized poppyseed oil containing 200 mg of iodine. They were followed for 1 y with measurements of urinary iodine (UI), thyrotropin (TSH), thyroxine (T4), and thyroid volume by ultrasound. Results: At baseline all children were goitrous and Se de®cient; median UI was 29 mgal and mean serum Se (s.d.) was 14.8 (10.7) mgal. After receiving iodized oil, thyroid volume decreased signi®cantly vs baseline at 10, 15, 30 and 50 weeks (P`0.001). At 50 weeks mean percentage change in thyroid volume from baseline was746.6% and only ®ve children remained goitrous. Median TSH values at 5, 10, 15, 30 and 50 weeks were reduced signi®cantly (P`0.001) compared to baseline. Among individual children the severity of Se de®ciency predicted the degree of response to iodized oil. Baseline serum Se and percentage change in thyroid volume from baseline at 50 weeks were strongly correlated (r 2 0.554). Baseline Se and percentage decrease in TSH from baseline at 30 weeks were also well-correlated (r 2 0.467). Conclusion: Although more severe Se de®ciency partially blunts the thyroid response to iodine supplementation, oral iodized oil is an effective method for iodine repletion in goitrous children who are Se de®cient.

Selenium status, thyroid volume, and multiple nodule formation in an area with mild iodine deficiency

“…Results from other studies examining the relation between selenium and thyroid volume differ (8)(9)(10)(23)(24)(25)(26)(27)(28). However, the results from our study are in line with results from the largest study carried out so far regarding selenium and thyroid volume (11).…”

Iron Deficiency in Goitrous Schoolchildren of Semirom, Iran

“…On the other hand, in iodine-deficient areas, multiple nutritional factors, including goitrogenic foods, protein-energy malnutrition, and selenium deficiency may influence the prevalence and severity of IDD and modify the response to iodine supplementation [4,5,6,7]. …”

An overview of interactions between micronutrients and of micronutrients with drugs, genes and immune mechanisms

“…Thyrodoxin is a specific seleno-peroxidase found in the thyroid where it removes peroxides (Howie et al 1998). Se deficiency partially blunts the thyroid response to I supplements (Zimmermann et al 2003). The clinical effect of this may be that in children with both deficiencies, the combined deficiencies may worsen the goitrous condition and/or lead to its earlier appearance, although oral iodised oil is an effective method of I repletion in goitrous children.…”