Immunosuppressant use among RA patients may protect against Alzheimer's disease

Among patients with rheumatoid arthritis (RA), treatment with immunosuppressants may partly attenuate the risk of Alzheimer’s disease (AD), according to a study.

Researchers used data from the National Health and Nutrition Examination Survey 2011-2014 and identified 217 RA patients at least 60 years of age who were receiving medications. The main outcome was cognitive function, assessed using the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) assessment battery, Animal Fluency Test (AFT), and a global cognition z-score (Z-score).

Multivariable linear regression was applied to examine the associations between immunosuppressant use and cognition. Additionally, two-sample Mendelian randomization (MR) and multivariable MR analyses were conducted to examine potential causal effects.

Patients with RA using immunosuppressants performed well on the DSST (p=0.036) and had a favourable global cognition Z-score (p=0.032).

In two-sample MR analysis, genetically predicted RA was associated with lower Alzheimer’s disease risk (odds ratio [OR], 0.936; p=4.531E−04), and this effect was largely mediated by immunosuppressant use. Multivariable MR validated the independent neuroprotective effect of immunosuppressant on Alzheimer’s disease risk (OR, 0.884; p=0.003) following adjustments for glucocorticoid and NSAID use, while other medications showed no significant association with the risk of Alzheimer’s disease.

The findings highlight the potential role of immunosuppressants in improving cognitive function and modulating Alzheimer’s disease risk in RA.