Thyroid Dysfunction Risk After Iodinated Contrast Media Administration: A Prospective Longitudinal Cohort Analysis

Area of Science:

• Endocrinology
• Radiology
• Public Health

Background:

• Iodinated contrast media (ICM) are frequently used in radiologic procedures.
• ICM administration represents a significant source of excess iodine exposure in healthcare settings.

Purpose of the Study:

• To prospectively evaluate the long-term risks of thyroid dysfunction after iodinated contrast administration.
• To assess longitudinal changes in thyroid hormone levels following ICM exposure.

Main Methods:

• A longitudinal cohort study involving 122 US Veterans Affairs patients who received ICM.
• Serum thyroid function, antibodies, and inflammatory markers were measured at baseline and followed for up to 36 months.
• Mixed-effects models were used to analyze the risk of thyroid dysfunction and hormone level changes.

Main Results:

• 11.5% of participants developed iodine-induced thyroid dysfunction over a median 18-month follow-up.
• New-onset hyperthyroidism (4.9%) and subclinical hypothyroidism (6.6%) were observed.
• Subtle longitudinal changes in thyroid hormones within reference ranges were noted in the cohort.

Conclusions:

• A rare but persistent risk of thyroid dysfunction exists following excess iodine load from ICM.
• Targeted thyroid monitoring is warranted for patients after iodinated contrast administration, even in iodine-sufficient populations.