A longer period of treatment with non-steroid anti-inflammatory drugs (NSAIDs) was associated with a decreased risk of dementia among patients with rheumatoid arthritis (RA) in a large population-based cohort, according to recent findings published in Medicine.
Previous studies have suggested that early inflammation, cardiovascular disease, and depression are associated with increased risk of dementia. The authors of the study noted that NSAIDs are “commonly used for treating RA, and several studies suggest that NSAIDs reduce the risk of Alzheimer disease (AD) or dementia in patients with RA.”
Using data from the Registry of the Catastrophic Illnesses Patient Database, a Taiwanese nationwide database created to track major illnesses, researchers examined a cohort of 33 229 patients at least 20 years of age with newly diagnosed RA between 2000 and 2011. A second cohort of 132 916 patients without RA was frequency matched with the RA cohort according to age, sex, and year of RA diagnosis.
The risk of dementia among participants with RA was not significantly higher than the participants without RA (3.34 vs 3.74 per 1000 person years; adjusted hazard ratio [HR]: 0.95; 95% confidence interval [CI]: 0.87-1.02).
When researchers compared duration of NSAID treatment, the risk of dementia was significantly lower for participants with RA who used NSAIDs for more than 2191 days compared with the participants who used NSAIDs for less than 730 days (HR: 0.56; 95% CI: 0.45-0.68).
“Our findings reveal no significant association between the risk of dementia and RA,” the authors concluded. “Nevertheless, it is suggested that prolonged use of NSAIDs reduces the risk of dementia in patients with RA. Because of the limitations of the NHIRD [National Health Insurance Research Database], it is necessary to conduct an experimental study determining the mechanism underlying the association of dementia risk with NSAID treatment in patients with RA.”
Summary and Clinical Applicability
NSAIDs are commonly used to alleviate RA-associated chronic pain, inflammation and swelling. Researchers conducted a study to evaluate the association between dementia risk and NSAID treatment in individuals with RA. While there was no observed association between RA risk and dementia risk, prolonged NSAID treatment was associated with reduced incidence of dementia.
The true baseline risk of dementia in RA patients, however, was difficult to estimate, limited by the availability of data from the NHIRD. Results from testing for neurocognitive pathology such as serum electrolytes, electroencephalograms, and neuroimaging were lacking in the database.
Further research should be conducted to determine the mechanism causing the association between dementia risk and NSAID treatment.
Chang KH, Hsu YC, Hsu CC, et al. Prolong Exposure of NSAID in Patients with RA Will Decrease Risk of Dementia. Medicine. 2016; 95(10):1-6. doi: 10.1097/MD.0000000000003056.