RESUMO
Objective@#To investigate the effects of different developmental patterns on the increases of thyroid volume in children from different genders and periods, and to explore whether there is a synergistic effect on the initiation of puberty in girls, so as to provide a theoretical basis for reducing the risk of thyroid abnormalities in adulthood.@*Methods@#A multi-stage cluster sampling was used to select a primary school in Minhang District of Shanghai, Haimen City of Jiangsu Province and Yuhuan city of Zhejiang Province. A total of 784 children aged 8-10 years old were included in "8-10 years school-aged children cohort". At the same time, a total of 491 girls aged 11-13 years were included in the "11-13 years adolescent girls cohort". The content of survey on follow-up was consistent with the one on baseline. B-ultrasonography was used to measure thyroid volume. The physical development indexes such as height (H), weight (W) and waist circumference (WC) were measured. The morning urine samples were collected and the urinary iodine content was detected. The changes of body mass index (BMI), waist circumference (WC), and thyroid volume (V) were calculated (d BMI, d WC, and d V, respectively). According to the changes of BMI and WC, the subjects were classified into four types of developmental changes, namely "B-LW-L (low d BMI, low d WC)" "B-LW-H (low d BMI, high d WC)" "B-HW-L (high d BMI, low d WC)" and "B-HW-H (high d BMI , high d WC)". Results In partial correlation analysis, thyroid volume was significantly correlated with BMI and WC at baseline or follow-up(P<0.05). The changes of thyroid volume in 8-10 years old boys were related to the changes of BMI and WC (P<0.05), the changes of thyroid volume in 8-10 year old girls were only associated with the changes of WC (P=0.03), and no association was found in 11-13 year old girls(P>0.05). In multivariate logistic regression analysis, after adjusting for baseline age, region, and differences of urinary iodine, the risk of thyroid volume increasing in B-HW-H was 2.70 times (95%CI=1.29-5.66) higher than that of B-LW-L in boys aged 8-10 years; among girls aged 11-13 years, the risk of thyroid volume increasing in B-LW-H, B-HW-L and B-HW-H were 2.46 times (95%CI=1.31-4.61), 2.16 times (95%CI=1.15-4.03) and 1.79 times (95%CI=1.07-2.99), respectively; there was no interaction between menarche age and developmental pattern on thyroid volume change trend (P=0.49).@*Conclusion@#The thyroid volume in children and adolescents increases with the development of physical development. Different developmental patterns and estrogens have certain effects on thyroid morphological changes. To avoid obesity in childhood (especially with central obesity), timely identify and effectively intervene thyroid morphological abnormalities in childhood，and to reduce the risk of thyroid diseases in adulthood.