A study published in the journal RMD Open has found a link between the inflammatory activity caused by rheumatoid arthritis (RA) and specific cognitive impairments. These impairments include diminished visuospatial abilities, recall, abstract thinking, and executive functions such as working memory, concentration, and inhibition.
The study aimed to identify which cognitive domains are specifically affected by the inflammatory activity associated with RA, a systemic disease known to have various effects on the brain.
To explore this, researchers conducted a comparative study involving 70 adults with RA and 70 age, sex, and education-matched volunteers without RA.
The RA group consisted of predominantly women with an average age of 56. Most of these patients exhibited moderate to high levels of systemic inflammation, despite undergoing conventional drug treatments, and had been living with the disease for an average of 10.5 years.
Both groups were subjected to comprehensive neurological and psychological assessments, including various validated cognitive tests and evaluations of mood and quality of life, over a year-long period.
The study revealed that RA patients scored lower on the Montreal Cognitive Assessment (MoCA) compared to the control group, indicating a higher prevalence of cognitive impairment among them. Specifically, 60% of RA patients were cognitively impaired versus 40% of the control group.
The RA patients also exhibited lower scores in executive functions and higher levels of anxiety and depression, coupled with a poorer quality of life. Factors such as age, educational attainment, and coexisting conditions like obesity, unhealthy blood fat levels, and high blood pressure were more prevalent among the cognitively impaired.
The research highlighted that persistent inflammatory activity and obesity were significant risk factors for cognitive impairment in RA patients. Obesity increased the risk almost sixfold, while ongoing inflammatory activity doubled the risk.
The study suggested that chronic inflammation, autoimmune processes, and symptoms like pain and fatigue in RA patients might contribute to the reduction in cognitive function. These findings align with previous suggestions linking chronic systemic inflammation in RA to broader health impacts.
The study’s authors acknowledge that their research is observational and cannot definitively establish causality. They also noted limitations such as the absence of imaging tests to detect vascular damage related to cognitive impairment.
Nevertheless, they concluded that their results support the hypothesis that RA is a chronic inflammatory disease affecting multiple systems, including neural tissue.
They emphasized the importance of early and stringent control of RA activity and the need for new therapeutic strategies to mitigate the risk of cognitive impairment in RA patients.