Association of serum selenium with thyroxin in severely iodine-deficient young children from the Amhara region of Ethiopia.

BACKGROUND/OBJECTIVES: Selenium (Se) as part of glutathione peroxidase and iodothyronine deiodinase enzymes influences thyroid metabolism. This study investigated the association of serum Se levels with thyroid metabolism of severely iodine-deficient young children from the Amhara region of Ethiopia.

SUBJECTS/METHODS: In a cross-sectional study, Se, thyroid-stimulating hormone, total thyroxin, total triiodothyronine and thyroglobulin in serum of children (N=628) 54-60 months of age from the Amhara region, Ethiopia, were analyzed. In addition, iodine in urine and household salt was analyzed, and the presence of goiter was assessed.

RESULTS

The median serum Se concentration was 61.4 μg/l (10.7-290.9 μg/l). Selenium deficiency (serum Se <70 μg/l) was detected in 57.8% (N=349) of the children. The median urinary iodine concentration (UIC) was 9.8 μg/l. The majority (86.6%, N=449) of children had UIC below the recommended value (100 μg/l). In addition, 59.8% (N=310) of children were severely iodine deficient (UIC<20 μg/l). Only 12.7% of salt samples had iodine. Goiter was present in 44.6% (N=280) of the children. Selenium-deficient children had higher serum thyroxin (T4) than children with normal serum Se concentration (P<0.001).

CONCLUSIONS

Serum Se was negatively associated with T4 level in young children from the Amhara region of Ethiopia and may endanger the effectiveness of the salt iodization program.