Patients with rheumatoid arthritis who take biologic or targeted synthetic disease-modifying anti-rheumatic drugs have a 17% lower incidence of dementia than patients who take conventional, synthetic DMARDs alone, a new study finds.

The reduced risk may be due to an overall decrease in inflammation brought about by the combination drug treatment, said lead study author Sebastian Sattui, M.D., a rheumatology fellow at Hospital for Special Surgery in New York City. No significant differences in dementia outcomes were tied to the different classes of biologic or targeted synthetic DMARDs.

“Our work shows yet another dimension in which treatment of rheumatoid arthritis can impact the overall health and quality of life of our patients,” Sattui said. “Rheumatoid arthritis is a systemic disease, and it can have cognitive implications. [M]edications that we use to treat rheumatoid arthritis could be effective in the prevention of dementia in patients with rheumatoid arthritis.”

Investigators used health data from 140,000 Medicare beneficiaries with rheumatoid arthritis collected between 2006 and 2017. The results were adjusted for age, sex and other comorbidities.

Conventional, synthetic DMARDs include the commonly prescribed methotrexate or sulfasalazine. Biologics include Orencia and Rituxan, and targeted synthetic DMARDs include the drugs tofacitinib and baricitinib. Doctors prescribe biologics when DMARDs alone aren’t enough to treat RA symptoms.

Notably, new RA treatment guidelines unveiled this week encourage a step back from steroid use and a move toward biologic and synthetic therapies.

The current study was presented last week at the virtual annual meeting of the American College of Rheumatology.