Anti-rheumatic drugs may be able to prevent thyroid disease

The findings were reported in the Journal of Internal Medicine.

Rheumatoid arthritis patients are more likely to develop autoimmune thyroid diseases such as Hashimoto's disease and Graves' disease. Immunomodulatory drugs, which alter the immune system, are routinely used to treat RA patients, but they are rarely utilised to address autoimmune thyroid disorders.

Thyroid hormone is instead utilised to compensate for the defects in normal thyroid function caused by autoimmune thyroid illness.

The current study sought to determine whether immunomodulatory medicines that lower inflammation in the joints of RA patients could also lessen the chance of these patients acquiring autoimmune thyroid illness.

Previous research in mice suggests that DMARDs, a type of immune-modulatory medicine used to treat rheumatoid arthritis, can lower thyroid gland inflammation. According to the research team, knowledge of whether this impact also extends to humans is limited.

The researchers analysed data from over 13,000 patients with rheumatoid arthritis and their treatments between 2006 and 2018, as well as data from over 63,000 people in a matched control group who did not have rheumatoid arthritis.The researchers discovered that the chance of acquiring an autoimmune thyroid illness in RA patients was lower after the disease's commencement than before diagnosis.

Patients with rheumatoid arthritis who were treated with immunomodulatory medications, or 'biological DMARDs,' had the greatest reduction in the incidence of autoimmune thyroid illness. The probability of autoimmune thyroid illness in these patients was 46% lower than in the control group without rheumatoid arthritis.

"These results support the hypothesis that certain types of immunomodulatory drugs could have a preventive effect on autoimmune thyroid disease," said Kristin Waldenlind, researcher at the Department of Medicine, Solna, Division of Clinical Epidemiology, Karolinska Institutet, specialist in rheumatology at Karolinska University Hospital and first author of the study.

"Our results do not prove that it is the treatment with immunomodulatory drugs that led to the reduced risk of autoimmune thyroid disease, but provide support for this hypothesis. The results, if they can be replicated in further studies, open up the possibility of studying more directly in clinical trials whether the immunomodulatory drugs currently used for rheumatoid arthritis could also be used for the early treatment of autoimmune thyroid disease, i.e. for new areas of use of these drugs, known as drug repurposing." (ANI)