A Swedish register–based cohort study found that rheumatoid arthritis may be associated with faster cognitive decline and an increased risk of all-cause mortality in patients with dementia.

In the study, published in Neurology, investigators analyzed 6,740 patients with dementia—1,685 of whom had rheumatoid arthritis (RA) and 5,055 of whom didn't have RA—over a median follow-up of 2.8 years. Cognitive function was assessed using Mini-Mental State Examination (MMSE) scores, and mortality risk was tracked through national registries.

Among the key findings were:

• Cognitive Decline: Patients with RA had a 0.24-point/year faster MMSE decline (95% confidence interval [CI] = −0.38 to −0.10, P = .001) compared with patients without RA.
• Mortality Risk: Patients with RA faced a 15% higher mortality risk (hazard ratio [HR] = 1.15, 95% CI = 1.06–1.24, P = .001).
• RA Duration Impact: Patients with 5 to 10 years of RA prior to dementia experienced faster cognitive decline (beta = −0.29 points/year, P = .001).
• Medication Effects: Use of disease-modifying antirheumatic drugs, with or without glucocorticoids, correlated with faster cognitive decline.

"We found that RA was associated with cognitive worsening in patients with dementia and an increased risk of mortality compared with [patients with] non-RA dementia. Our findings highlight the importance of appropriate management and treatment for dementia patients with RA," said lead study author Minjia Mo, of the Division of Clinical Geriatrics of the Department of Neurobiology of the Care Sciences and Society at the Karolinska Institutet in Sweden.

The results suggested that chronic systemic inflammation in RA may accelerate dementia progression, although further research is needed to clarify underlying mechanisms.

This large-scale study underscored the need for tailored clinical management among patients with dementia and RA to mitigate cognitive decline and reduce mortality risks.

Full disclosures are detailed in the study.