Abstract
OBJECTIVE: Tumor necrosis factor alpha inhibitors are frequently used in the treatment of axial spondyloarthritis. While tumor necrosis factor alpha is associated with some malignancies, studies on its effects on thyroid functions and thyroid nodules are limited. This study aimed to assess the effect of tumor necrosis factor alpha inhibitors treatments on the evaluation of thyroid nodules and thyroid function tests in axial spondyloarthritis patients. METHODS: A total of 106 patients with axial spondyloarthritis, 48 receiving nonsteroidal antiinflammatory drugs and 58 receiving tumor necrosis factor alpha inhibitors, were included in the study. All cases were screened by ultrasound for the presence of nodules, European Thyroid Association - Thyroid Imaging Reporting and Data System classification category, thyroid volume, and thyroid function tests. RESULTS: The prevalence of patients with multiple nodules in the tumor necrosis factor alpha inhibitors treatment group was significantly higher compared to the nonsteroidal antiinflammatory drug group (68.2 vs. 38.1%, p=0.033). Furthermore, the prevalence of nodules measuring ≥1 cm in the tumor necrosis factor alpha inhibitors treatment group was higher compared to the only nonsteroidal antiinflammatory drug treatment group (56 vs. 19.05%, p=0.011). In the tumor necrosis factor alpha inhibitors treatment group, the proportion of patients with nodules requiring fine-needle aspiration cytology was higher compared to the nonsteroidal antiinflammatory drug group (34.5 vs. 16.7%, p=0.038). No significant difference was found between thyroid-stimulating hormone and free thyroxine values before and during treatment in both groups (p>0.005). CONCLUSION: The number of nodules requiring fine-needle aspiration cytology according to the European Thyroid Association - Thyroid Imaging Reporting and Data System classification seems higher in nonsteroidal antiinflammatory drugs users than Tumor necrosis factor-alpha inhibitor users. Therefore, it may be rational to examine the thyroid gland while administering Tumor necrosis factor-alpha inhibitor treatment in axial spondyloarthritis patients.