Rheumatoid Arthritis Drugs May Prevent Thyroid Disease

Anti-rheumatic drugs used for rheumatoid arthritis might prevent the development of autoimmune thyroid disease, according to a new observational study by researchers from Karolinska Institutet published in the Journal of Internal Medicine.

It is well known that patients with rheumatoid arthritis (RA) are at increased risk of autoimmune thyroid diseases such as Hashimoto's disease and Graves' disease. While patients with RA are usually treated with immunomodulatory drugs that affect the immune system, such drugs are rarely used in autoimmune thyroid diseases.

Instead, such patients are treated with thyroid hormone to compensate for the changes in normal thyroid function that accompany autoimmune thyroid disease. 

The researchers in the current study wanted to investigate whether immunomodulatory drugs that reduce inflammation in the joints of patients with RA might also reduce the risk of these patients developing autoimmune thyroid disease.

Previous studies in mice suggest that so-called DMARDs, a type of immune-modulatory drugs used to treat rheumatoid arthritis, can reduce inflammation in the thyroid gland. Still, knowledge of whether this effect also applies to humans is limited, according to the research team.