Objective: A recent study demonstrated that osteoprotegerin (OPG) could be expressed both in benign and malignant thyroid tissue. However, epidemiologic studies investigating the association between serum OPG and thyroid nodules are not available. The objective of this study was to determine whether serum OPG is associated with thyroid nodules.
Methods: We measured serum OPG, total triiodothyronine, total thyroxine, free triiodothyronine, free thyroxine, thyrotropin, antithyroid peroxidase antibodies, thyrotropin-receptor antibodies, antithyroglobulin antibodies, and thyroglobulin in 1,120 Chinese participants in a cross-sectional community-based study performed in downtown Shanghai. Thyroid nodule was diagnosed by thyroid ultrasonographic examination.
Results: The serum OPG levels were significantly increased in nodule-positive subjects compared to nodule-negative subjects (2.8 ± 1.2 ng/mL versus 2.1 ± 1.0 ng/mL; P<.001). After multiple adjustments, the odds ratios were substantially higher for thyroid nodule (odds ratio, 3.09; 95% confidence interval, 1.60 to 5.97) in the highest OPG quartile compared with those in the lowest quartile. These associations remained significant after further adjustment for potential confounders. Multivariate linear regression analysis demonstrated that age (P = .015) and OPG (P = .003) were independently associated with thyroid nodule.
Conclusion: Serum OPG is elevated significantly in subjects with thyroid nodules among middle-aged and elderly individuals.