Prevalence of goiter among schoolchildren from Gorgan, Iran, a decade after national iodine supplementation: association with age, gender, and thyroperoxidase antibodies.
BACKGROUND
One decade after universal salt iodization in Iran, goiter prevalence, urinary iodine concentration (UIC) and thyroperoxidase antibody (TPOAb) values were assessed among schoolchildren in Gorgan, Iran.


METHODS
From 2003-2004, 500 girls and 900 boys aged 7-11 yr were evaluated for goiter by palpation. UIC was measured in 183 randomly-selected goitrous children. Serum TSH, T4, and TPOAb were measured in 53 goitrous and 30 non-goitrous children with adequate UIC.


RESULTS
Goiter was detected in 370 (26.4%) children. Goiter was present in 31% of girls and 17% of boys age 9 (p<0.012); 37% of girls and 20% of boys age 10 (p<0.003); and 52% of girls and 19% of boys age 11 (p<0.0001). Median (range) UIC for all goitrous children sampled was 190 (20-600) microg/l; 220 (30590) in boys and 170 (20-600) in girls (p=0.001). Eight point seven percent of goitrous children and 22% of goitrous girls aged 10-11 had UIC<100 microg/l, while 47% of the goitrous children had UIC> or =200 microg/ l. TPOAb was present in 52.8% of goitrous children and 10% of non-goitrous children (p=0.0001). TPOAb was present in 53.9% of 10-11 and 22.7% of 7-9 yr old goitrous and non-goitrous children (p=0.003) with adequate UIC. Median (range) TSH was 2.9 (0.3-10.9) mlU/I in TPO-positive and 1.8 (0.5-4.1) in TPO-negative children (p=0.001).


CONCLUSIONS
Gorgan, Iran, is an iodine-sufficient area and almost half of schoolchildren have more than adequate UIC. TPOAb is associated with endemic goiter. Despite sufficient UIC overall, some school-aged girls remain at risk of iodine deficiency.
Bazrafshan
H R
HR
Gorgan Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran.
Mohammadian
S
S
Ordookhani
A
A
Farhidmehr
F
F
Hedayati
M
M
Abdolahi
N
N
Azizi
F
F
Braverman
L E
LE
Pearce
E N
EN
D000367:Age Factors; D001323:Autoantibodies / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006042:Goiter / Q000097:blood / Q000453:epidemiology* / Q000276:immunology / Q000652:urine; D006801:Humans; D007453:Iodide Peroxidase / Q000097:blood / Q000276:immunology*; D007455:Iodine / Q000008:administration & dosage / Q000652:urine; D007492:Iran / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012737:Sex Factors; D013954:Thyroglobulin / Q000097:blood; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D001323:Autoantibodies; D014284:Triiodothyronine; D013972:Thyrotropin; D013954:Thyroglobulin; D007455:Iodine; D007453:Iodide Peroxidase; D013974:Thyroxine