Correlation between thyroid function indices and urine iodine levels in patients with nodular goiter

Objective: To retrospectively analyze the iodine nutritional status in patients with nodular goiter (NG) and investigate a possible association between urinary iodine levels and thyroid function indices. Methods: A total of 173 patients diagnosed with nodular goiter in the Fourth Hospital of Hebei Medical University from January 2019 to May 2021 were selected as the NG group, and 172 healthy individuals without thyroid diseases were selected after a physical examination as a control group. The data of all the participants were retrospectively assessed to explore the association between urinary iodine levels and thyroid function indices. The content of urinary iodine in the two groups was compared, and the correlation of urinary iodine levels with thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) in the NG group was evaluated. Results: The level of urinary iodine in the NG group was 163.97 +/- 113.75 mu g/L, which was higher than 121.47 +/- 53.75 mu g/L in the control group (P < 0.05). The iodine excess rate in females was higher than that in males (P < 0.05). The results of Pearson correlation analysis showed that the amount of urinary iodine in patients with hyperthyroidism with different urinary iodine statuses was negatively correlated with the level of TSH and positively correlated with levels of FT3 and FT4. Conclusion: There is a significant association between urinary iodine levels and thyroid hormone levels in NG patients. Therefore, regular monitoring of urinary iodine levels is essential for the appropriate use of iodine supplementation.