Iodine deficiency is associated with increased thyroid hormone sensitivity in individuals with elevated TSH.

Thyroid hormone sensitivity and age have a U-shaped association in individuals with elevated TSH. Increased thyroid hormone sensitivity is associated with iodine deficiency and the female gender. Decreased thyroid hormone sensitivity is associated with TPOAb+. These findings are interesting and potentially useful for understanding the interaction between iodine nutrition and the hypothalamic-pituitary-thyroid axis.