Selenium status, thyroid volume, and multiple nodule formation in an area with mild iodine deficiency.
OBJECTIVE
The objective was to study the associations between serum selenium concentration and thyroid volume, as well as the association between serum selenium concentration and risk for an enlarged thyroid gland in an area with mild iodine deficiency before and after iodine fortification was introduced. Another objective was to examine the association between serum selenium concentration and prevalence of thyroid nodules.


METHODS
Cross-sectional study.


METHODS
We studied participants of two similar cross-sectional studies carried out before (1997-1998, n=405) and after (2004-2005, n=400) introduction of iodine fortification. Serum selenium concentration and urinary iodine were measured, and the thyroid gland was examined by ultrasonography in the same subjects. Associations between serum selenium concentration and thyroid parameters were examined in multiple linear regression models or logistic regression models.


RESULTS
Serum selenium concentration was found to be significantly, negatively associated with thyroid volume (P=0.006), and a low selenium status significantly increased the risk for thyroid enlargement (P=0.007). Furthermore, low serum selenium status had a tendency to increase the risk for development of multiple nodules (P=0.087).


CONCLUSIONS
Low serum selenium concentration was associated with a larger thyroid volume and a higher prevalence of thyroid enlargement.
Division of Nutrition, Department of Nutrition, National Food Institute, Technical University of Denmark, Mørkhøj Bygade 19, DK-2860 Søborg, Denmark. lbra@food.dtu.dk
Lone Banke
LB
Rasmussen
Lutz
L
Schomburg
Josef
J
Köhrle
Inge Bülow
IB
Pedersen
Birgit
B
Hollenbach
Antonia
A
Hög
Lars
L
Ovesen
Hans
H
Perrild
Peter
P
Laurberg
D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007455:Iodine / Q000172:deficiency* / Q000652:urine; D008297:Male; D008875:Middle Aged; D012643:Selenium / Q000097:blood*; D013959:Thyroid Diseases / Q000097:blood* / Q000000981:diagnostic imaging; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D014463:Ultrasonography; D055815:Young Adult
D007455:Iodine; D012643:Selenium