DMARD use is associated with a higher risk of dementia in patients with rheumatoid arthritis: A propensity score-matched case control study

Background: Patients with rheumatoid arthritis (RA) exhibit an increased risk of dementia. Disease-modifying antirheumatic drugs (DMARDs) are commonly used to slow RA progression, but studies investigating the relationship between DMARDs and dementia in patients with RA are lacking. We investigated the relationship between DMARDs and dementia in patients with RA. Methods: Using the National Health Insurance Research Database, patients aged 20 years, who were newly diagnosed with RA between 2000 and 2011 were identified. Patients with RA who had dementia comprised the dementia group, and patients with RA who did not have dementia comprised the control group. The groups were matched at a 1:1 ratio by the propensity score. DMARDs were categorized into conventional synthetic DMARDs (csDMARDs) and biological DMARDs (bDMARDs). Logistic regression models were used to calculate the odds ratio and 95% confidence interval (CI) to evaluate the association between DMARD use and the risk of dementia in patients with RA. Results: A total of 957 patients with RA and dementia, and 957 patients with RA but not dementia, were enrolled. The risk of dementia was determined to be 1.63-fold higher in patients with RA with csDMARD use than in those without csDMARD use (95% CI = 1.33-2.00). No significant risk of dementia was observed in patients with RA who used bDMARDs compared with their counterparts. However, patients with RA who used hydroxychloroquine, methotrexate, and sulfasalazine exhibited significant risks of dementia, irrespective of cumulative exposure days. Conclusion: Patients with RA who used csDMARDs exhibit significant association with dementia.