A new study from Sweden has found that people with both dementia and rheumatoid arthritis (RA) may experience a faster decline in thinking and memory abilities than those with dementia alone.
The research, conducted by scientists at the Karolinska Institutet and published in the journal Neurology, is the first to establish a clear connection between these two chronic conditions and their combined effect on cognitive decline.
Rheumatoid arthritis is a long-term autoimmune disease that causes painful inflammation in the joints. It can also lead to problems in other parts of the body due to widespread inflammation.
Meanwhile, dementia, including Alzheimer’s disease, involves the gradual worsening of memory, judgment, and other mental abilities. Both diseases are more common in older adults, and this study shows that having RA may make the symptoms of dementia worse over time.
The researchers examined health records from the Swedish Registry for Cognitive/Dementia Disorders (SveDem), focusing on patients diagnosed between 2007 and 2018.
They studied 1,685 people who had both dementia and RA, and compared them to 5,055 dementia patients without RA. These two groups were matched based on age, sex, and other medical conditions to make the comparison fair.
Over a follow-up period of around three years, the study found that people with both dementia and RA had a faster drop in cognitive function, as measured by the Mini-Mental State Examination (MMSE)—a common test used to assess mental sharpness. They also faced a higher risk of death from all causes during the study period.
“Our results show that RA is associated with poorer cognitive outcomes in dementia patients, especially in those with Alzheimer’s disease or mixed Alzheimer’s dementia,” said Minjia Mo, a postdoctoral researcher at Karolinska Institutet and the lead author of the study.
“This underscores the importance of identifying inflammatory risk factors to help slow or prevent the progression of dementia.”
The researchers believe that inflammation may be the key link between RA and worsening dementia symptoms. In RA, the immune system attacks the body’s tissues, causing inflammation not only in the joints but possibly also in the brain.
This brain inflammation, known as neuroinflammation, may speed up the damage that leads to memory loss and other cognitive issues.
Hong Xu, assistant professor at Karolinska and the study’s senior author, says their team is now working on a deeper investigation into this possible link.
“We plan to continue our research to understand how systemic inflammation in RA contributes to neuroinflammation and cognitive decline,” he said. “We will study specific inflammatory markers and examine whether RA treatments that reduce inflammation could also help slow down dementia.”
The researchers hope their findings will raise awareness among doctors and healthcare providers. They believe that people with both RA and dementia may benefit from more careful monitoring, regular cognitive testing, and possibly new treatment approaches that address inflammation as a shared factor between the two conditions.
In summary, this study highlights an important but often overlooked connection between two serious conditions. For patients and their families, it offers new insight into why dementia might progress faster in some people, and why managing chronic inflammation could be a key part of slowing that progression in the future.
If you care about dementia, please read studies about Vitamin B9 deficiency linked to higher dementia risk, and flavonoid-rich foods could help prevent dementia.
For more information about brain health, please see recent studies that cranberries could help boost memory, and how alcohol, coffee and tea intake influence cognitive decline.
The research findings can be found in Neurology.
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