TY - JOUR
T1 - Treatment of iodine deficiency in school-age children increases 1GF-1 and IGFBP-3 concentrations and improvves somatic growth
AU - Zimmermann, M.B.
AU - Jooste, P.L.
AU - Solomon Mabapa, N.
AU - Mbhenyane, X.
AU - Schoeman, S.
AU - Biebinger, R.
AU - Chaouki, N.
AU - Bozo, M.
AU - Grimci, L.
AU - Bridson, J.
PY - 2007
Y1 - 2007
N2 - Objective: To determine if iodine repletion improves somatic growth in iodine-deficient children and to investigate the role of insulin-like growth factor (IGF)-1 and insulin-like growth factor binding protein (IGFBP)-3 in this effect.
Design, participants, and interventions: Three prospective, double blind intervention studies were done: 1) in a 10 month study, severely iodine-deficient, 7-10 y-old Moroccan children (n = 71) were provided iodized salt and compared with children not using iodized salt; 2) in a 6 month study, moderately iodine-deficient, 10-12 y-old Albanian children (n = 310) were given 400 mg iodine as oral iodized oil or placebo; 3) in a 6 month study, mildly iodine-deficient 5-14 y-old South African children (n = 188) were given two doses of 200 mg iodine as oral iodized oil or placebo. At baseline and follow-up, height, weight, urinary iodine (UI), total thyroxine (TT4), thyroid-stimulating hormone (TSH) and IGF-I were measured; in Albania and South Africa, IGFBP-3 was also measured.
Results: In all three studies, iodine treatment increased median UI to >100 µg/L, while median UI in the controls remained unchanged. In South Africa, iodine repletion modestly increased IGF-1, but did not have a significant effect on IGFBP-3, TT4 or growth. In Albania and Morocco, iodine repletion significantly increased TT4, IGF-1, IGFBP-3, weight-for-age z scores and height-for-age z scores.
Conclusion: This is the first controlled study to clearly demonstrate that iodine repletion in school-age children increases IGF-1 and IGFBP-3 concentrations and improves somatic growth.
AB - Objective: To determine if iodine repletion improves somatic growth in iodine-deficient children and to investigate the role of insulin-like growth factor (IGF)-1 and insulin-like growth factor binding protein (IGFBP)-3 in this effect.
Design, participants, and interventions: Three prospective, double blind intervention studies were done: 1) in a 10 month study, severely iodine-deficient, 7-10 y-old Moroccan children (n = 71) were provided iodized salt and compared with children not using iodized salt; 2) in a 6 month study, moderately iodine-deficient, 10-12 y-old Albanian children (n = 310) were given 400 mg iodine as oral iodized oil or placebo; 3) in a 6 month study, mildly iodine-deficient 5-14 y-old South African children (n = 188) were given two doses of 200 mg iodine as oral iodized oil or placebo. At baseline and follow-up, height, weight, urinary iodine (UI), total thyroxine (TT4), thyroid-stimulating hormone (TSH) and IGF-I were measured; in Albania and South Africa, IGFBP-3 was also measured.
Results: In all three studies, iodine treatment increased median UI to >100 µg/L, while median UI in the controls remained unchanged. In South Africa, iodine repletion modestly increased IGF-1, but did not have a significant effect on IGFBP-3, TT4 or growth. In Albania and Morocco, iodine repletion significantly increased TT4, IGF-1, IGFBP-3, weight-for-age z scores and height-for-age z scores.
Conclusion: This is the first controlled study to clearly demonstrate that iodine repletion in school-age children increases IGF-1 and IGFBP-3 concentrations and improves somatic growth.
KW - factor-i
KW - thyroid-hormone
KW - endemic goiter
KW - rat
KW - supplementation
KW - cells
KW - hyperthyroidism
KW - hypothyroidism
KW - schoolchildren
KW - dysfunction
U2 - 10.1210/jc.2006-1901
DO - 10.1210/jc.2006-1901
M3 - Article
SN - 0021-972X
VL - 92
SP - 437
EP - 442
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 2
ER -