Factors influencing thyroid volume in Chinese children.

BACKGROUND/OBJECTIVES: This paper aims to compare children's thyroid volume (Tvol) by age and gender in Zhejiang province in order to explore the factors influencing Tvol in this area.

SUBJECTS/METHODS: This survey was a cross-sectional survey of a provincial representative sample of Zhejiang province children aged 6-12 years. The children were asked to provide a urine sample for the determination of urinary iodine concentration (UIC) and thyroid ultrasonography was performed for the determination of Tvol.

RESULTS

The median (25th, 75th percentile) of UIC in children aged 6-12 years in Zhejiang province was found to be 170.0(111.2, 244.4) μg/l. The median (25th, 75th percentile) of Tvols was found to be 3.1(2.3, 4.2) ml. There were significant differences among the different age groups on BSA (Z=-17.911, P=0.000) and Tvol (Z=-1.996, P=0.046) but not on UIC and body mass index (P>0.05). Tvol was in significant association with BSA (P=0.000) but was not associated with UIC (P>0.05). Age, gender and BSA were significant in multiple linear regression (P<0.05).

CONCLUSIONS

The median UIC of children aged 6-12 years falls in the optimal iodine status as recommended by WHO/UNICEF/ICCIDD. However, urinary iodine nutritional status had little effect on the Tvol in children aged 6-12 years in Zhejiang province. Age, gender and BSA were the influencing factors of Tvol.