Association of thyroid gland volume, serum insulin-like growth factor-I, and anthropometric variables in euthyroid prepubertal children.
OBJECTIVE
Few studies have focused on the interrelation between thyroid size, anthropometric variables, and IGF-I in adults, but such data are lacking for children. We have investigated thyroid gland volume and several hormonal and anthropometric variables in prepubertal children.


METHODS
A total of 859 prepubertal euthyroid Danish children aged 4-9 yr underwent a thorough clinical investigation, including anthropometrical measurements and determination of TSH, thyroid hormones, autoantibodies, urinary iodine excretion, and thyroid volume (TV) by ultrasound. Longitudinal growth data from birth were available.


RESULTS
TV increased significantly with age (r = 0.487; P < 0.001). Mean TV +/- sd for different age groups were as follows: 4 yr, 2.2 +/- 1.4 ml; 5 yr, 2.5 +/- 1.3 ml; 6 yr, 2.8 +/- 1.3 ml; 7 yr, 3.2 +/- 1.3 ml; 8 yr, 3.5 +/- 1.3 ml; 9 yr, 3.7 +/- 1.3 ml. We found a significant positive association between IGF-I and TV (P < 0.001). Furthermore, in multiple regression analyses, TSH (P < 0.013), free T(4) (P < 0.001), lean body mass (P < 0.001), and body surface area (P < 0.001) as well as other anthropometrical measurements were identified as factors significantly associated with TV. Family history of thyroid disease and presence of incidental abnormal ultrasound findings were also positively associated with TV (P = 0.025 and 0.022, respectively).


CONCLUSIONS
In our cohort of prepubertal Danish children, the GH/IGF-I-axis was positively correlated with thyroid size, suggesting a role in the regulation of thyroid growth. Moreover, anthropometric measurements, in particular body surface area, were the best predictors of TV.
Boas
Malene
M
University Department of Growth and Reproduction, Rigshospitalet, DK-2100 Copenhagen, Denmark. malene.boas@rh.regionh.dk
Hegedüs
Laszlo
L
Feldt-Rasmussen
Ulla
U
Skakkebaek
Niels E
NE
Hilsted
Linda
L
Main
Katharina M
KM
D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood / Q000378:metabolism* / Q000652:urine; D049628:Body Size; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D003718:Denmark; D005260:Female; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007455:Iodine / Q000652:urine; D008297:Male; D009035:Mothers; D011627:Puberty; D011795:Surveys and Questionnaires; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D013963:Thyroid Hormones / Q000097:blood; D013972:Thyrotropin / Q000097:blood; D014463:Ultrasonography
D001323:Autoantibodies; D015415:Biomarkers; D013963:Thyroid Hormones; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013972:Thyrotropin; D007455:Iodine