The Relationship between Thyroid Nodules Detected through Ultrasonography and Thyroid Function Test Results in Healthy Individuals

ABSTRACT

BACKGROUND: The detection of thyroid nodules through ultrasonography (US) has improved with the development of imaging technologies and thyroid cancer screening in Korea. We evaluated the relationship between the presence of thyroid nodules on US and thyroid function test (TFT) results in healthy individuals.METHODS: We performed a retrospective review of data from 449 adults (313 men and 136 women) who underwent tests to evaluate serum thyrotropin (TSH) and free thyroxine levels, thyroid US, and if needed, fine needle aspiration cytology (FNAC).RESULTS: Of the 449 subjects, 144 subjects (32.1%) had thyroid nodules. Among the 144 with thyroid nodules, 24 (16.7%) were advised to undergo FNAC, and all of them showed normal serum TSH levels. Logistic regression analysis showed that the presence of thyroid nodules was not related to abnormalities noted on TFTs after adjusting for age, sex, smoking status, and presence of risky drinking behavior and hypertension (P=0.647).CONCLUSION: The presence of thyroid nodules on US in healthy adults was not associated with abnormal TFT results. Serum TSH check-ups during the evaluation of thyroid nodules discovered through US in asymptomatic individuals living in areas with a low prevalence of autonomous functioning thyroid nodules might not be necessary from the perspective of cost-effectiveness and subject convenience.