He N L, Li H, An W, Yang M
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Department of Mathematical Science, Tsinghua University, Beijing 100084, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2020 Nov 6;54(11):1268-1274. doi: 10.3760/cma.j.cn112150-20200322-00403.
To establish an asymmetric U-shaped response relationship between urinary iodine level and thyroid nodule prevalence. Taking "Iodine" "Urine Iodine" "Thyroid" and "Thyroid Nodule" as Chinese keywords, and "Urine Iodine" "Goiter" and "Thyroid Nodule" as English keywords, literatures about urine iodine level and thyroid nodule prevalence were searched in China Biology Medicine disc, China National Knowledge Internet, Wanfang Data, PubMed and Springer databases from January 2000 to December 2019 respectively. The language of literatures was restricted in Chinese and English. There were 46 articles (24 domestic and 22 foreign) included in the study. The quantile regression method and Sigmoid function model were used to fit the dose-response relationship between different levels of urinary iodine and thyroid nodule prevalence to estimate the prevalence of thyroid nodule in Chinese residents. The fitted dose-response curves between different levels of urine iodine, ranging from low level to appropriate level and then to high level, and thyroid nodule prevalence had a good performance on the simulation of the asymmetric U-shaped relationship between urine iodine level and thyroid nodule prevalence. The median level of urinary iodine at the cut-off point of the piecewise function was 198 μg/L. Based on the weighted calculation of the total sample size included in the literature, the prevalence of thyroid nodules (95%) in Chinese residents was 23.0% (17.3%-30.7%). The asymmetric U-shaped response relationship between urinary iodine level and thyroid nodule prevalence based on piecewise function has good feasibility and fitting effect.
建立尿碘水平与甲状腺结节患病率之间的非对称U型反应关系。以“碘”“尿碘”“甲状腺”和“甲状腺结节”作为中文关键词，以“Urine Iodine”“Goiter”和“Thyroid Nodule”作为英文关键词，分别在中国生物医学光盘数据库、中国知网、万方数据、PubMed和Springer数据库中检索2000年1月至2019年12月期间关于尿碘水平与甲状腺结节患病率的文献。文献语言限制为中文和英文。本研究共纳入46篇文章（国内24篇，国外22篇）。采用分位数回归方法和Sigmoid函数模型拟合不同水平尿碘与甲状腺结节患病率之间的剂量反应关系，以估算中国居民甲状腺结节的患病率。不同水平尿碘（从低水平到适宜水平再到高水平）与甲状腺结节患病率之间拟合的剂量反应曲线，在模拟尿碘水平与甲状腺结节患病率之间的非对称U型关系方面表现良好。分段函数切点处尿碘的中位数水平为198μg/L。基于文献中纳入的总样本量加权计算，中国居民甲状腺结节的患病率（95%）为23.0%（17.3%-30.7%）。基于分段函数的尿碘水平与甲状腺结节患病率之间的非对称U型反应关系具有良好的可行性和拟合效果。
