Establishment of a medical reference range of serum iodine in adults with normal thyroid function in Fujian Province / 中华地方病学杂志

ABSTRACT

Objective:To establish a medical reference range of serum iodine in adults with normal thyroid function in Fujian Province.Methods:Permanent residents aged 16 - 60 years old and living in the local area for 5 years and more were selected as survey subjects in three areas with appropriate iodine nutrition in Fujian Province from September 2019 to January 2020. Urine and blood samples were collected to detect urinary iodine, serum iodine and thyroid function indexes [thyroid stimulating hormone (TSH), thyroglobulin (Tg), free triiodothyronine (FT 3), free thyroxine (FT 4), total triiodothyronine (TT 3), total thyroxine (TT 4), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb)] levels. The percentile method was used to establish the 95% medical reference range of serum iodine in adults with normal thyroid function, and Pearson correlation analysis was used to analyze the correlation between serum iodine and thyroid function indexes in adults with normal thyroid function. Results:A total of 149 adults with normal thyroid function were examined, and the median urinary iodine was 119.45 μg/L, which was at the appropriate level (100 - 199 μg/L); serum iodine was (61.35 ± 16.20) μg/L, and the 95% medical reference range of serum iodine in adults with normal thyroid function was preliminarily formulated as 34.36 - 97.17 μg/L. Correlation analysis showed that serum iodine was positively correlated with FT 4 level ( r = 0.17, P = 0.035), but was not correlated with other thyroid function indexes ( P > 0.05). Conclusion:The medical reference range of serum iodine in adults with normal thyroid function in Fujian Province is successfully established, which provides a basis for judgment of individual iodine nutrition in adults.