Associations of demographic, anthropometric, and laboratory factors with Korean Thyroid Imaging Reporting and Data System (K-TIRADS) ultrasonographic risk stratification in patients with thyroid nodules.

Thyroid nodules are commonly detected by ultrasonography and require standardized imaging-based risk stratification. The Korean Thyroid Imaging Reporting and Data System (K-TIRADS) classifies thyroid nodules according to ultrasonographic features associated with suspected malignancy; however, factors associated with higher K-TIRADS classification remain incompletely understood. The aim of this study was to evaluate the associations of demographic, anthropometric, and laboratory factors with K-TIRADS ultrasonographic risk stratification in patients with thyroid nodules. A cross-sectional study was conducted at Dr. Zainoel Abidin Hospital, Banda Aceh, Indonesia. Adult patients with clinically suspected thyroid nodules were included using total sampling. Thyroid ultrasonography was performed using a standardized protocol, and nodules were classified according to the 2021 K-TIRADS. Demographic, anthropometric, and laboratory factors included age, sex, body mass index (BMI), and serum thyroid-stimulating hormone (TSH) level. Generalized estimating equations (GEE) were used to assess associations while accounting for clustering of multiple nodules within the same patient. A total of 109 patients with 171 thyroid nodules were included. Most patients were female (81.7%), with a median age of 46 years (IQR 34-59). Most nodules were classified as K-TIRADS 3 (48.0%) or K-TIRADS 4 (35.7%). Univariate analyses suggested that age was significantly associated with higher K-TIRADS classification (β=0.010; 95%CI: 0.003- 0.018; p=0.008), whereas sex, BMI, and serum TSH level were not significant. In multivariable analysis, increasing age (β=0.010; 95%CI: 0.002-0.018; p=0.012) and higher serum TSH level (β=0.007; 95%CI: 0.002-0.011; p=0.002) were independently associated with higher K-TIRADS classification. No significant associations were observed for sex or BMI. The findings highlight that increasing age and higher serum TSH level were independently associated with higher K-TIRADS ultrasonographic risk stratification in patients with thyroid nodules. Selected demographic and laboratory factors may complement the ultrasonography-based classification system.