Mingyue Jin1, Zhuo Zhang1, Yongze Li1, Di Teng1, Xiaoguang Shi1, Jianming Ba2, Bing Chen3, Jianling Du4, Lanjie He5, Xiaoyang Lai6, Xiaochun Teng1, Yanbo Li7, Haiyi Chi8, Eryuan Liao9, Chao Liu10, Libin Liu11, Guijun Qin12, Yingfen Qin13, Huibiao Quan14, Bingyin Shi15, Hui Sun16, Xulei Tang17, Nanwei Tong18, Guixia Wang19, Jin-An Zhang20, Youmin Wang21, Yuanming Xue22, Li Yan23, Jing Yang24, Lihui Yang25, Yongli Yao26, Zhen Ye27, Qiao Zhang28, Lihui Zhang29, Jun Zhu30, Mei Zhu31, Guang Ning32, Yiming Mu2, Jiajun Zhao33, Weiping Teng1, Zhongyan Shan1. 1. Department of Endocrinology and Metabolism and the Institute of Endocrinology, The First Hospital of China Medical University, Shenyang, Liaoning, P.R. China. 2. Department of Endocrinology, Chinese PLA General Hospital, Beijing, P.R. China. 3. Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing, P.R. China. 4. Department of Endocrinology, The First Affiliated Hospital of Dalian Medical University, Dalian, P.R. China. 5. Department of Endocrinology, Cardiovascular and Cerebrovascular Disease Hospital of Ningxia Medical University, Yinchuan, P.R. China. 6. Department of Endocrinology and Metabolism, The Second Affiliated Hospital of Nanchang University, Nanchang, P.R. China. 7. Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, P.R. China. 8. Department of Endocrinology, Hohhot First Hospital, Hohhot, P.R. China. 9. Department of Endocrinology and Metabolism, The Second Xiangya Hospital, Central South University, Changsha, P.R. China. 10. Research Center of Endocrine and Metabolic Diseases, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, P.R. China. 11. Department of Endocrinology and Metabolism, Fujian Institute of Endocrinology, Fujian Medical University Union Hospital, Fuzhou, P.R. China. 12. Division of Endocrinology, Department of Internal Medicine, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, P.R. China. 13. Department of Endocrine, First Affiliated Hospital of Guangxi Medical University, Nanning, P.R. China. 14. Department of Endocrinology, Hainan General Hospital, Haikou, P.R. China. 15. Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, P.R. China. 16. Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China. 17. Department of Endocrinology, The First Hospital of Lanzhou University, Lanzhou, P.R. China. 18. Department of Endocrinology and Metabolism, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, P.R. China. 19. Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, P.R. China. 20. Department of Endocrinology, Shanghai University of Medicine & Health Science Affiliated Zhoupu Hospital, Shanghai, P.R. China. 21. Department of Endocrinology, The First Hospital of An Hui Medical University, Hefei, P.R. China. 22. Department of Endocrinology, The First People's Hospital of Yunnan Province, Kunming, P.R. China. 23. Department of Endocrinology and Metabolism, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P.R. China. 24. Department of Endocrinology, The First Hospital of Shanxi Medical University, Taiyuan, P.R. China. 25. Department of Endocrinology and Metabolism, People's Hospital of Tibet Autonomous Region, Lhasa, P.R. China. 26. Department of Endocrinology, Qinghai Provincial People's Hospital, Xining, P.R. China. 27. Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, P.R. China. 28. Department of Endocrinology and Metabolism, Affiliated Hospital of Guiyang Medical University, Guiyang, P.R. China. 29. Department of Endocrinology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China. 30. Department of Endocrinology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, P.R. China. 31. Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, P.R. China. 32. Department of Endocrinology and Metabolism and the Institute of Endocrinology, Rui-Jin Hospital Affiliated with Shanghai Jiao-Tong University School of Medicine, Shanghai, P.R. China. 33. Department of Endocrinology, Shandong Provincial Hospital affiliated with Shandong University, Jinan, P.R. China.
Abstract
Background: Iodine is important in both thyroid function and human metabolism. Studies have explored the effect of iodine on metabolic disorders through thyroid function. This study aimed to investigate the relationship between iodine status and metabolic disorders, such as metabolic syndrome (MetS), hypertension, impaired glucose metabolism, central obesity, and dyslipidemia. Methods: A total of 51,795 subjects aged ≥18 years from the TIDE (Thyroid Disorders, Iodine Status and Diabetes, a national epidemiological cross-sectional study) program were included. The prevalence of metabolic disorders and its related diseases was calculated based on the level of urinary iodine concentrations (UICs) using the chi-square method. To further explore whether the prevalence was associated with UIC, quadratic and UIC-stratified logistic regression models were used. Results: The prevalence of metabolic disorders as a function of UIC was found to be U-shaped with a lower prevalence of 76.0% at an UIC of 300-499 μg/L. Participants with an UIC of 300-499 μg/L showed an association with metabolic disorders (odds ratio [OR] = 0.857, 95% confidence interval [CI 0.796-0.922]) and hypertension (OR = 0.873 [CI 0.814-0.936]). An UIC of 300-799 μg/L was found to be associated with the occurrence of MetS and impaired glucose tolerance. An UIC of 500-799 μg/L was associated with the occurrence of prediabetes (OR = 0.883 [CI 0.797-0.978]). An UIC of ≥300 μg/L was associated with the occurrence of hypertriglyceridemia, hypercholesterolemia, and high levels of low-density lipoprotein cholesterol. Furthermore, an UIC of <100 μg/L showed an association with hypertension (OR = 1.097 [CI 1.035-1.162]) and hypercholesterolemia (OR = 1.178 [CI 1.117-1.242]). Conclusions: The association between UICs in adults and metabolic disorders and its related diseases is U-shaped. The association between UIC and metabolic disorders disappears in cases of iodine deficiency (<100 μg/L) or excess (≥500 μg/L).
Background: Iodine is important in both thyroid function and human metabolism. Studies have explored the effect of iodine on metabolic disorders through thyroid function. This study aimed to investigate the relationship between iodine status and metabolic disorders, such as metabolic syndrome (MetS), hypertension, impaired glucose metabolism, central obesity, and dyslipidemia. Methods: A total of 51,795 subjects aged ≥18 years from the TIDE (Thyroid Disorders, IodineStatus and Diabetes, a national epidemiological cross-sectional study) program were included. The prevalence of metabolic disorders and its related diseases was calculated based on the level of urinary iodine concentrations (UICs) using the chi-square method. To further explore whether the prevalence was associated with UIC, quadratic and UIC-stratified logistic regression models were used. Results: The prevalence of metabolic disorders as a function of UIC was found to be U-shaped with a lower prevalence of 76.0% at an UIC of 300-499 μg/L. Participants with an UIC of 300-499 μg/L showed an association with metabolic disorders (odds ratio [OR] = 0.857, 95% confidence interval [CI 0.796-0.922]) and hypertension (OR = 0.873 [CI 0.814-0.936]). An UIC of 300-799 μg/L was found to be associated with the occurrence of MetS and impaired glucose tolerance. An UIC of 500-799 μg/L was associated with the occurrence of prediabetes (OR = 0.883 [CI 0.797-0.978]). An UIC of ≥300 μg/L was associated with the occurrence of hypertriglyceridemia, hypercholesterolemia, and high levels of low-density lipoprotein cholesterol. Furthermore, an UIC of <100 μg/L showed an association with hypertension (OR = 1.097 [CI 1.035-1.162]) and hypercholesterolemia (OR = 1.178 [CI 1.117-1.242]). Conclusions: The association between UICs in adults and metabolic disorders and its related diseases is U-shaped. The association between UIC and metabolic disorders disappears in cases of iodine deficiency (<100 μg/L) or excess (≥500 μg/L).