İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, Department of Pediatrics, Division of Pediatric Endocrinology, İstanbul, Turkey
İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, Department of Medical Biochemistry, İstanbul, Turkey
J Clin Res Pediatr Endocrinol. 2021 Jun 2;13(2):152-159. doi: 10.4274/jcrpe.galenos.2020.2020.0170. Epub 2020 Oct 2.
Obesity is known to affect thyroid function. Recently, waist-height ratio (WHtR) has been considered as a useful marker of subclinical hypothyroidism in obese cases, but its relation with thyroid autoimmunity still remains unclear. We evaluated the effect of body fat mass, WHtR, and metabolic parameters on thyroid autoantibody levels in children with obesity.
This was a cross-sectional study carried out with an obese [n=56, male/female (M/F): 29/26] and a healthy group (n=38, M/F: 19/19). All subjects underwent anthropometric measurements, laboratory investigations for thyroid function tests, thyroid peroxidase (TPO-ab) and thyroglobulin-antibodies (Tg-ab), transaminases, blood glucose, insulin levels, and lipids after overnight fasting; homeostatic model assessment for insulin resistance (HOMA-IR) was calculated for assessment of insulin resistance. Fat mass was estimated by multiple frequency bioimpedance analysis in the obese group, which was further divided into two subgroups according to the median of WHtR. All parameters were compared between the groups/subgroups.
In the obese group, weight, height, body mass index (BMI), free triiodothyronine, thyrotropin, TPO-ab, insulin, low density lipoprotein-cholesterol, total cholesterol, alanine aminotransferase levels, and HOMA-IR were significantly higher than the controls group (p<0.05 for all). Median of WHtR was 0.6 in the obese group. In the “WHtR >0.6” subgroup (n=28), weight, BMI, fat mass, TPO-ab, Tg-ab, insulin and triglyceride levels were higher than WHtR ≤0.6 subgroup (p<0.05). A positive correlation was obtained between Tg-ab and WHtR (rho=0.28, p=0.041).
Euthyroid children with obesity and a WHtR >0.6 are likely to have higher thyroid antibody levels, and Tg-ab levels have a positive correlation with WHtR, which reveals an association of central adiposity with thyroid autoantibody levels in these cases.
肥胖已知会影响甲状腺功能。最近，腰高比（WHtR）已被认为是肥胖患者亚临床甲状腺功能减退的有用标志物，但它与甲状腺自身免疫的关系仍不清楚。我们评估了体脂肪量、WHtR 和代谢参数对肥胖儿童甲状腺自身抗体水平的影响。
这是一项横断面研究，纳入了肥胖组[n=56，男/女（M/F）：29/26]和健康对照组[n=38，M/F：19/19]。所有受试者均接受了体格测量、甲状腺功能试验、甲状腺过氧化物酶（TPO-ab）和甲状腺球蛋白抗体（Tg-ab）、转氨酶、空腹血糖、胰岛素水平和血脂检测；计算稳态模型评估的胰岛素抵抗指数（HOMA-IR）以评估胰岛素抵抗。肥胖组采用多频生物阻抗分析估计脂肪量，根据 WHtR 的中位数进一步将其分为两组。比较两组/亚组之间的所有参数。
肥胖组的体重、身高、体重指数（BMI）、游离三碘甲状腺原氨酸、促甲状腺激素、TPO-ab、胰岛素、低密度脂蛋白胆固醇、总胆固醇、丙氨酸氨基转移酶水平和 HOMA-IR 均显著高于对照组（p<0.05）。肥胖组的 WHtR 中位数为 0.6。在“WHtR>0.6”亚组（n=28）中，体重、BMI、脂肪量、TPO-ab、Tg-ab、胰岛素和甘油三酯水平均高于 WHtR≤0.6 亚组（p<0.05）。Tg-ab 与 WHtR 呈正相关（rho=0.28，p=0.041）。
WHtR>0.6 的甲状腺功能正常的肥胖儿童可能具有更高的甲状腺抗体水平，且 Tg-ab 水平与 WHtR 呈正相关，这表明在这些病例中，中心性肥胖与甲状腺自身抗体水平有关。
