Abstract
OBJECTIVES: This large-scale cross-sectional study utilized electronic health records (EHRs) to determine the prevalence, sonographic characteristics, and independent correlates of thyroid nodules in a Chinese health examination cohort, with comprehensive adjustment for iodine status, thyroid function, and autoantibodies. METHODS: We analyzed data from 12,468 adults undergoing routine check-ups in 2024. Thyroid nodules were assessed via ultrasonography and classified using TI-RADS. Multivariable logistic regression identified factors independently associated with nodule presence. RESULTS: The prevalence of thyroid nodules was 35.36%, with the vast majority (96.01%) being benign or probably benign (TI-RADS 2-3). Independent correlates included female sex (OR = 1.65, 95% CI:1.51-1.80), older age (per 10-year increment, OR = 1.55, 95% CI:1.47-1.64), family history of thyroid disease (OR = 2.31, 95% CI:2.04-2.61), insufficient iodine intake (OR = 1.38, 95% CI:1.23-1.55), obesity (OR = 1.35, 95% CI:1.21-1.50), abnormal TSH (OR = 1.32, 95% CI:1.19-1.46), and TPOAb positivity (OR = 1.28, 95% CI:1.13-1.45). Regular moderate-to-vigorous physical activity was protective (OR = 0.73, 95% CI:0.66-0.81). CONCLUSION: Thyroid nodules are highly prevalent in this population. We identified a profile of both non-modifiable (e.g., sex, age) and modifiable (e.g., iodine nutrition, obesity, physical activity) correlates. These findings highlight targets for preventive health strategies, though future prospective studies in the general population are warranted to confirm causality.