Abstract:Objective To investigate the value of multimodal metabolic and blood biomarkers combined with thyroid ultrasound characteristics in distinguishing benign low-risk from high-risk thyroid nodules, and to construct a risk prediction nomogram model for high-risk nodules.Methods A total of 8 141 patients with thyroid nodules detected at the Health Management Center of Huai'an First People's Hospital from May 2024 to April 2025 were enrolled. According to the Thyroid Imaging Reporting and Data System (TI-RADS) classification criteria, category 4 nodules (4a, 4b, and 4c) were defined as the high-risk group (n = 111), while categories 1-3 nodules were defined as the low-risk group (n = 8 030). Differences in levels of multimodal metabolic and blood markers and ultrasound characteristics of thyroid nodules were compared between the groups. Independent risk factors for high-risk nodules were analyzed using a multivariable logistic regression model, and a nomogram along with a calibration curve was constructed to predict the occurrence of high-risk thyroid nodules.Results The high-risk group exhibited higher age and levels of TSH and LDL-C (P < 0.05), while FT4 levels were lower in the high-risk group than in the low-risk group (P < 0.05). The low-risk group had higher proportions of nodules with grades 0 and I blood flow, clear margins, and regular morphology (P < 0.05), alongside lower rates of nodules with calcification and internal hypoechogenicity compared to the high-risk group (P < 0.05). Multivariable logistic regression analysis revealed that advanced age [O^R = 1.036 (95% CI: 1.011, 1.061) ], elevated TSH levels [O^R = 1.058 (95% CI: 1.017, 1.100) ], high LDL-C levels [O^R = 1.644 (95% CI: 1.065, 2.537) ], calcification [O^R = 12.767 (95% CI: 6.583, 24.762) ], grade Ⅱ~Ⅲ blood flow [O^R = 10.351 (95% CI: 5.347, 20.038) ], and internal hypoechogenicity [O^R = 17.075 (95% CI: 8.343, 34.943) ] were risk factors for high-risk thyroid nodules (P < 0.05). Conversely, elevated FT4 levels [O^R = 0.826 (95% CI: 0.700, 0.973) ], well-defined borders [O^R = 0.046 (95% CI: 0.023, 0.091) ], and regular morphology [O^R = 0.019 (95% CI: 0.009, 0.039) ] were protective factors against high-risk thyroid nodules (P < 0.05). A nomogram model for predicting high-risk thyroid nodules was constructed.Conclusion The nomogram model, constructed based on multimodal metabolic and blood biomarkers and thyroid ultrasound characteristics, effectively distinguishes between high-risk and low-risk thyroid nodules, providing a quantitative tool for clinical decision-making.