Department of Endocrinology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China.
Department of Dermatology, The First Affiliated Hospital of Jinan University, Guangzhou, China.
Obes Facts. 2023;16(5):497-506. doi: 10.1159/000533157. Epub 2023 Aug 11.
Obesity contributes to the pathogenesis of diverse metabolic diseases, yet the mechanism underlying metabolically healthy obesity (MHO) remains elusive. Thyroid hormones and sensitivity to them have a major impact on metabolism. Our study aimed to investigate the association between MHO and thyroid hormone sensitivity.
Thyroid hormone indices, including the thyroid-stimulating hormone (TSH) index (TSHI), the Thyrotroph Thyroxine Sensitivity Index (TTSI), the Thyroid Feedback Quantile-Based Index (TFQI), and the Parametric Thyroid Feedback Quantile-Based Index (PTFQI), were calculated based on a non-institutionalized US sample in the National Health and Nutrition Examination Survey (NHANES, 2007-2012). Participants were divided into four groups (metabolically healthy non-obesity [MHNO], metabolically unhealthy non-obesity [MUNO], MHO, and metabolically unhealthy obesity [MUO]) according to their body mass index and metabolic profiles. Linear regression, logistic regression, and restricted cubic splines were employed to analyze the association between thyroid hormone indices and metabolic phenotypes.
A total of 4,857 participants (49.6% men; mean age, 42.6 years) were included, with 1,539 having obesity and 235 identified as MHO. Participants in the MHO group exhibited lower levels of TSH, TSHI, TTSI, TFQI, and PTFQI compared with the MHNO group (all p < 0.05), while the differences among MHNO, MUNO, and MUO groups were not statistically significant (all p > 0.05). Among participants with obesity, TSH, TSHI, TTSI, TFQI, and PTFQI were positively associated with metabolic abnormality (all p < 0.05).
Participants with MHO exhibited higher thyroid hormone sensitivity among various obesity phenotypes, even when compared with those with MHNO. A positive association was observed between metabolic abnormality and thyroid hormone sensitivity, while the trend of TSH was observed to be consistent with sensitivity to thyroid hormone indices in discriminating metabolic abnormality. Hence, TSH has the potential to serve as a convenient index for detecting sensitivity to thyroid hormones and further metabolic conditions.
肥胖是多种代谢性疾病发病机制的一个重要因素，然而代谢健康型肥胖（MHO）的发病机制仍不清楚。甲状腺激素及其敏感性对代谢有重大影响。本研究旨在探讨 MHO 与甲状腺激素敏感性之间的关系。
根据美国国家健康和营养检查调查（NHANES，2007-2012）中的非机构化样本，计算了甲状腺激素指数，包括促甲状腺激素（TSH）指数（TSHI）、促甲状腺激素敏感性指数（TTSI）、甲状腺反馈定量指数（TFQI）和参数甲状腺反馈定量指数（PTFQI）。根据体重指数和代谢特征，将参与者分为四组（代谢健康非肥胖[MHNO]、代谢不健康非肥胖[MUNO]、MHO 和代谢不健康肥胖[MUO]）。采用线性回归、逻辑回归和限制立方样条分析甲状腺激素指数与代谢表型之间的关系。
共纳入 4857 名参与者（49.6%为男性；平均年龄为 42.6 岁），其中 1539 名肥胖者和 235 名 MHO。与 MHNO 组相比，MHO 组的 TSH、TSHI、TTSI、TFQI 和 PTFQI 水平较低（均 P < 0.05），而 MHNO、MUNO 和 MUO 组之间的差异无统计学意义（均 P > 0.05）。在肥胖者中，TSH、TSHI、TTSI、TFQI 和 PTFQI 与代谢异常呈正相关（均 P < 0.05）。
在各种肥胖表型中，MHO 参与者的甲状腺激素敏感性较高，甚至与 MHNO 相比也是如此。代谢异常与甲状腺激素敏感性之间存在正相关关系，而 TSH 趋势与甲状腺激素指数在区分代谢异常方面的敏感性一致。因此，TSH 有可能成为检测甲状腺激素敏感性和进一步代谢状况的便捷指标。
