流行病学研究表明，身高增加与甲状腺功能减退症或甲状腺癌的风险增加有关。然而，身高与甲状腺功能减退或甲状腺癌之间的潜在因果关系尚未得到彻底探索。自身免疫性甲状腺疾病（AITD）主要表现为甲状腺功能减退症，因此，我们的目的是评估身高暴露与AITD或甲状腺癌之间的因果关系。使用与身高相关的遗传仪器进行孟德尔随机化（MR）分析，其中是从最大的全基因组关联荟萃分析中选出的，对多达 540 万人的身高进行了分析。 AITD 和甲状腺癌的摘要级数据，分别包括 30,234 例和 3,001 例病例，是从现有的大型全基因组关联研究中收集的。进行双向 MR 来测试 AITD 与成人身高之间的反向因果关系。MR 分析显示，遗传预测身高增加与 AITD 风险增加 4% 相关（[95% CI 1.02, 1.07]，pvalue=1.99E-03 ），基因预测身高每增加 1 个标准差 (SD)。双向 MR 未显示 AITD 与成人身高之间存在任何因果关系。此外，身高每增加 1-SD，遗传预测身高增加与甲状腺癌风险增加 15% 相关（[95% CI 1.07, 1.23]，pvalue=2.32E-04）。敏感性分析证实了主要结果。这项 MR 研究表明，遗传预测身高增加一个标准差与 AITD 和甲状腺癌的风险增加相关。相比之下，没有证据表明基因预测的 AITD 与身高存在因果关系。这些结果可能会进一步帮助对身高相关通路的研究，作为获得 AITD 和甲状腺癌新机制见解的一种手段。

Increased height has been associated with increased risk of hypothyroidism or thyroid cancer in epidemiological studies. However, the potential causal association between height and hypothyroidism or thyroid cancer have not been thoroughly explored. Autoimmune thyroid disease (AITD) mainly presents as hypothyroidism, thus, we aim to evaluate the causal relationship between height as exposure and its association with AITD or thyroid cancer.Mendelian randomisation (MR) analyses were performed by using genetic instruments associated with height, which were selected from the largest genome-wide association meta-analysis for height in up to 5.4 million individuals. Summary-level data for AITD and thyroid cancer, including 30,234 and 3,001 cases respectively, were collected from the large available genome-wide association studies. Bidirectional MR was performed to test for reverse causal association between AITD and adult height.MR analyses showed that increased genetically predicted height was associated with a 4% increased risk of AITD ([95% CI 1.02, 1.07], pvalue=1.99E-03), per 1 standard deviation (SD) increase in genetically predicted height. The bidirectional MR did not show any causal association between AITD and adult height. Additionally, increased genetically predicted height was associated with 15% increased risk of thyroid cancer ([95% CI 1.07, 1.23], pvalue=2.32E-04), per 1-SD increase in height. Sensitivity analysis confirmed the main results.This MR study showed that one standard deviation increased genetically predicted height was associated with increased risk of AITD and thyroid cancer. In contrast, there was no evidence of a causal association of genetically predicted AITD on height. These results could be further aiding the investigation of height-related pathways as a means for gaining new mechanistic insights into AITD and thyroid cancer.