Background This study aimed to assess the effects of iodine intake, thyroid function, and their combined effect on the risk of papillary thyroid cancer (PTC) and papillary thyroid microcarcinoma (PTMC).
Methods A case-control study was conducted including 500 community-based controls who had undergone a health check-up, and 446 overall PTC cases (209 PTC and 237 PTMC) from the Thyroid Cancer Longitudinal Study. Urinary iodine concentration (UIC), was used as an indicator of iodine intake, and serum for thyroid function. The risk of PTC and PTMC was estimated using unconditional logistic regression.
Results Excessive iodine intake (UIC ≥220 μg/gCr) was associated with both PTC (odds ratio [OR], 18.13 95% confidence interval [CI], 8.87 to 37.04) and PTMC (OR, 8.02; 95% CI, 4.64 to 13.87), compared to adequate iodine intake (UIC, 85 to 219 μg/gCr). Free thyroxine (T4) levels ≥1.25 ng/dL were associated with PTC (OR, 1.97; 95% CI, 1.36 to 2.87) and PTMC (OR, 2.98; 95% CI, 2.01 to 4.41), compared to free T4 levels of 0.7 to 1.24 ng/dL. Individuals with excessive iodine intake and high free T4 levels had a greatly increased OR of PTC (OR, 43.48; 95% CI, 12.63 to 149.62), and PTMC (OR, 26.96; 95% CI, 10.26 to 70.89), compared to individuals with adequate iodine intake and low free T4 levels.
Conclusion Excessive iodine intake using creatinine-adjusted UIC and high free T4 levels may have a synergistic effect on PTC and PTMC. Considering both iodine intake and thyroid function is important to assess PTC and PTMC risk.
Citations
Citations to this article as recorded by
Association between urinary iodine concentration and the risk of papillary thyroid cancer by sex and age: a case–control study Yerin Hwang, Hyun-Kyung Oh, Jae Hoon Chung, Sun Wook Kim, Jung-Han Kim, Jee Soo Kim, Myung-Hee Shin Scientific Reports.2023;[Epub] CrossRef
Association between iodine nutrition and cervical lymph node metastasis of papillary thyroid microcarcinoma Hengqiang Zhao, Jin Hu, Le Cui, Yiping Gong, Tao Huang Frontiers in Endocrinology.2023;[Epub] CrossRef
Sex-specific Associations between Body Mass Index and Thyroid Cancer Incidence among Korean Adults Kyoung-Nam Kim, Kyungsik Kim, Sangjun Lee, Sue K. Park Cancer Epidemiology, Biomarkers & Prevention.2023; 32(9): 1227. CrossRef
Nomogram Model Based on Iodine Nutrition and Clinical Characteristics of Papillary Thyroid Carcinoma to Predict Lateral Lymph Node Metastasis Junrong Wang, Yuzhang Gao, Yuxuan Zong, Weitong Gao, Xueying Wang, Ji Sun, Susheng Miao Cancer Control.2023;[Epub] CrossRef
Content of Copper, Iron, Iodine, Rubidium, Strontium and Zinc in Thyroid Malignant Nodules and Thyroid Tissue adjacent to Nodules Vladimir Zaichick, Qiping Dong Journal of Clinical and Diagnostic Pathology.2022; 1(4): 7. CrossRef
Distinguish Thyroid Malignant from Benign Alterations using Trace Element Contents in Nodular Tissue determined by Neutron Activation and Inductively Coupled Plasma Mass Spectrometry Vladimir Zaichick Journal of Clinical and Diagnostic Pathology.2022; 1(4): 18. CrossRef
Seaweed and Iodine Intakes and SLC5A5 rs77277498 in Relation to Thyroid Cancer Tung Hoang, Eun Kyung Lee, Jeonghee Lee, Yul Hwangbo, Jeongseon Kim Endocrinology and Metabolism.2022; 37(3): 513. CrossRef
Iodine nutrition and papillary thyroid cancer Xueqi Zhang, Fan Zhang, Qiuxian Li, Chuyao Feng, Weiping Teng Frontiers in Nutrition.2022;[Epub] CrossRef
The relationship between urinary iodine concentration and papillary thyroid cancer: A systematic review and meta-analysis Xueqi Zhang, Fan Zhang, Qiuxian Li, Renaguli Aihaiti, Chuyao Feng, Deshi Chen, Xu Zhao, Weiping Teng Frontiers in Endocrinology.2022;[Epub] CrossRef
Screening and validation of lymph node metastasis risk-factor genes in papillary thyroid carcinoma Qiaoyue Zhang, Jing Li, Hengyan Shen, Xinyu Bai, Tao Zhang, Ping Liu Frontiers in Endocrinology.2022;[Epub] CrossRef
Diagnosis of Thyroid Malignancy using Levels of Chemical Element Contents in Nodular Tissue Vladimir Zaichick Journal of Health Care and Research.2022; 3(1): 16. CrossRef
Associations of Habitual Mineral Intake with New-Onset Prediabetes/Diabetes after Acute Pancreatitis Claire F. Norbitt, Wandia Kimita, Juyeon Ko, Sakina H. Bharmal, Maxim S. Petrov Nutrients.2021; 13(11): 3978. CrossRef