Treating iodine deficiency: long-term effects of iodine repletion on growth and pubertal development in school-age children.
BACKGROUND
Iodine deficiency (ID) is still a major universal health problem. Iodine deficiency disorders (IDDs) affect people of all ages, among whom the most vulnerable are children and adolescents. The aim of the present study was to assess the long-term effects on growth and pubertal development of correcting severe ID in areas of Azerbaijan between 1999 and 2000.


METHODS
Iodized oil was administered orally to 293,000 children, aged 6-16 years. Among those, 364 children were randomly selected and were examined 1 year before the administration of iodized oil (Group I-neg, iodine negative) and 295 children (Group I-Rx, iodine treated) were examined 4 years (Group I-R x 4, iodine treated 4 years later; n = 173) or 5 years (Group I-R x 5, iodine treated 5 years later; n = 122) after the last dose of iodide.


RESULTS
In Group I-neg the median urine iodine concentration (UIC) (mcg/L) was 36 (mean: 36.272 +/- 11.036) and increased significantly (p < 0.001) in Group I-R x 4: 188 (mean: 230.969 +/- 155.818) and in Group I-R x 5: 175 (mean: 201.176 +/- 130.369). The prevalence of goiter was 99% in Group I-neg and 2% in Group I-R x 4. Children in Group I-Rx had a greater standard deviation score (SDS) for height (-0.1364 +/- 1.279, n = 294) than children in Group I-neg (-0.5019 +/- 1.17, n = 363) (p < 0.001, t = -3.817), which was more significant for boys. SDS for weight was similar in both groups (Group I-neg: -0.17 +/- 0.78, n = 363; Group I-Rx: -0.115 +/- 0.917, n = 294). The rate of puberty development as judged by the development of breast and pubic hair was normalized in both sexes after the correction of ID.


CONCLUSIONS
Our results demonstrate that long-term correction of severe ID leads to sustained improvement of linear growth accompanied by a normalization of the time of onset of pubertal development for both sexes.
Markou
Kostas B
KB
Division of Endocrinology, Department of Internal Medicine, University of Patras Medical School, University Hospital, Patras, Greece.
Tsekouras
Athanasios
A
Anastasiou
Eleni
E
Vlassopoulou
Barbara
B
Koukkou
Eftychia
E
Vagenakis
George A
GA
Mylonas
Panagiotis
P
Vasilopoulos
Charalampos
C
Theodoropoulou
Anastasia
A
Rottstein
Loredana
L
Lampropoulou
Evgenia
E
Apostolopoulos
Dimitris
D
Jabarov
Rauf
R
Vagenakis
Apostolos G
AG
Georgopoulos
Neoklis A
NA
D000293:Adolescent; D001827:Body Height / Q000187:drug effects; D002648:Child; D005260:Female; D006042:Goiter / Q000188:drug therapy / Q000517:prevention & control; D006130:Growth Disorders / Q000188:drug therapy*; D006803:Human Development; D006801:Humans; D007455:Iodine / Q000172:deficiency* / Q000627:therapeutic use*; D008297:Male; D009821:Oils; D015995:Prevalence; D011627:Puberty; D013959:Thyroid Diseases / Q000188:drug therapy*; D013997:Time Factors; D016896:Treatment Outcome
D009821:Oils; D007455:Iodine