Inactivated SARS-CoV-2 vaccination does not disturb the clinical course of Graves' disease: An observational cohort study.

SARS-CoV-2 vaccination has been reported to be associated with the induction of thyroid disorders. To investigate the influence of SARS-CoV-2 vaccination on the disease course of patients who were undergoing treatment for Graves' disease (GD), a total of 651 consecutive GD patients who attended follow-up visits in Jiangyuan Hospital were enrolled in this retrospective study, including 443 inactivated SARS-CoV-2 vaccine recipients and 208 unvaccinated participants. The changes in serum levels of free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH) and TSH receptor antibody (TRAb) were analyzed. Crude and adjusted hazard ratios (HRs) were estimated using Cox regression models to investigate the risks in incident TRAb positivity and hyperthyroidism recurrence following vaccination. The median levels of TRAb and fT3 significantly decreased in both vaccinated and unvaccinated groups during the GD hyperthyroidism treatment. The fT4 levels of both groups were well within normal limits and presented downward trends simultaneously. Although the present study observed an increasing trend of TSH level during follow-up, significant difference was not seen in both vaccinated and unvaccinated groups. Except for newly diagnosed GD patients, vaccinated participants had significantly lower risks of incident TRAb positivity (adjusted HR = 0.22; 95%CI: 0.10-0.48, P < 0.001) after adjusted for sex, age, disease duration and MMI dose at baseline. Besides, vaccination was unlikely to serve as a risk factor for hyperthyroidism recurrence (adjusted HR = 1.20; 95%CI: 0.51-2.83, P = 0.678). Notably, newly diagnosed patients who received vaccination were just as likely to achieve remission of thyrotoxicosis as those not receiving the vaccination at any time. Our results concluded that inactivated SARS-CoV-2 vaccination would not disturb the treatment course among GD hyperthyroidism patients.