Thyroid Stimulating Hormone (TSH) Is Associated With General and Abdominal Obesity: A Cohort Study in School-Aged Girls During Puberty in East China

Abstract

<b>Objectives:</b> Although the association between thyroid stimulating hormone (TSH) and obesity in children has been investigated in several cross-sectional studies, no study evaluated this association among girls during puberty, which were in a key period closely related to the fluctuations of thyroid hormones and development of obesity. Therefore, we conducted a cohort study to investigate the association of general and abdominal obesity with TSH in girls during puberty. <b>Setting and participants:</b> A cohort study of 481 school-aged girls during puberty was conducted in four regions in east China, with a baseline survey in 2017 and a follow-up survey in 2019. <b>Outcome measures:</b> Anthropometric indexes including height, weight and waist circumference (WC) were measured, and body mass index (BMI) was then calculated. Blood samples were collected to determine TSH and free thyroxine (FT4). <b>Results:</b> Of the 474 girls at baseline survey, the prevalences of BMI-based general obesity and WC-based abdominal obesity were 19.8% (94/474) and 21.7% (103/474), respectively. Compared with normal weight girls, the median serum TSH level was significantly higher in general obese girls (<i>P</i> = 0.037), but not in central obese girls (<i>P</i> = 0.173). Multiple logistic regression models indicated that those in the highest tertile of serum TSH level had a significantly higher risk of BMI-based overweight/obesity (OR = 1.83, 95% CI 1.01 to 3.32) compared with the lowest tertile. Analyses from 435 girls prospectively followed-up for 2 years revealed that those with general or central obesity also had higher follow-up TSH level (<i>P</i> = 0.004 and <i>P</i> = 0.008, respectively). The TSH level for girls with general obesity at baseline but normal weight at follow-up was 0.45 mU/L (95% CI 0.11 to 0.79) higher than those with normal weight at baseline and follow-up. <b>Conclusions:</b> TSH was positively associated with both general and abdominal obesity among girls during puberty.