Relationship between Thyroid Nodules and Iodine Nutritional Status, Thyroglobulin (Tg), and Other Influencing Factors: A 1:1 Matched Case-Control Study

Qingying Lin¹Lijin Wang²Diqun Chen²Jiani Wu²Ying Lan²Qingdong Jin¹Yanqing Chen¹Zhihui Chen^2*Muhua Wang^2*

• ¹The First Hospital of Putian City, Putian, China
• ²Fujian Center for Disease Control and Provention, Fuzhou, China

Background: An increasing trend in the prevalence of thyroid nodules has highlighted whether thyroid nodules are related to the level of iodine nutrition. Methods: This 1:1 matched case-control study was conducted to investigate whether thyroid nodules are related to the level of iodine nutrition. The residents who had lived there for more than 5 years with thyroid nodules composed the case group. All the subjects completed questionnaires, and blood and urine samples were collected. Results: The MUI of the case group in areas with more than adequate iodine intake was lower than that of the control group (P<0.05); only the level of Tg in the case group was higher than that in the control group in areas with adequate iodine intake (P<0.05). The conditional logistic regression model revealed that there were significant correlations between a history of thyroid disorders, Tg, TgAb, and thyroid nodules. Conclusions: In areas with more than adequate iodine intake, a slight increase in urinary iodine may be associated with a lower risk of thyroid nodules. A history of thyroid disorders and increased Tg and TgAb levels are risk factors for thyroid nodules. Tg level detection has certain diagnostic value in distinguishing thyroid nodules.