Study Links Rheumatoid Arthritis to Accelerated Brain Aging
A new preprint study combining brain imaging, blood biomarkers, and genetic analysis found that rheumatoid arthritis (RA) patients show signs of brain aging approximately 6.5 years ahead of healthy peers. Researchers analyzed two independent patient cohorts from Gothenburg and Glasgow using MRI-based brain-age prediction models alongside neurodegeneration blood markers. The findings suggest chronic systemic inflammation in RA may drive measurable structural and molecular changes in the brain, with the strongest effects seen in patients over 60.
Researchers used structural MRI, circulating neurodegeneration biomarkers, and peripheral monocyte transcriptomics to assess brain aging in rheumatoid arthritis patients across two independent cohorts totaling 121 participants. A brain-age prediction model trained on healthy controls was applied to RA patients from Gothenburg (n=71) and Glasgow (n=50), revealing a corrected brain-age gap of +6.5 years (95% CI: 4.2–8.8 years, p<0.0001) compared to healthy individuals. The effect was substantially stronger in patients over 60, who also showed ventricular enlargement and reduced frontal and parietal lobe volumes. Blood levels of brain-derived tau and glial fibrillary acidic protein — both established markers of neurodegeneration and glial stress — were elevated in RA patients. The accelerated brain aging was further associated with altered myeloid transcriptional signatures in peripheral monocytes, pointing to a potential inflammatory immune mechanism. These converging lines of evidence suggest that the chronic systemic inflammation characteristic of RA may contribute to premature neurodegenerative processes. The study was posted as a preprint on bioRxiv and has not yet undergone formal peer review.
What's missing
The study does not clarify whether disease-modifying antirheumatic drugs (DMARDs) or biologics used to treat RA attenuate or exacerbate the observed brain-aging effects. The cross-sectional design prevents causal inference — it is unclear whether RA causes accelerated brain aging or whether shared underlying factors drive both. The study also does not address whether the observed brain-age gap translates into measurable cognitive decline or dementia risk in these patients.
What different sources said
- bioRxivCenter
Neurostructural and molecular evidence of advanced brain aging in rheumatoid arthritis
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