Most people recognize rheumatoid arthritis as a disease that weakens the joints. It is actually an autoimmune disease, where the immune system becomes confused and progressively attacks not just the joints but the eyes, blood vessels, and other parts of the body.
Many do not know that rheumatoid arthritis is also associated with an increased risk of cardiovascular disease. Not much information is available as to why rheumatoid arthritis patients also have many cardiovascular disease risk factors. Some point to the inflammation caused by the attacking immune system as a possibility, but no substantial evidence is available.
A team from the University of Milano in Italy wanted to investigate if the onset of rheumatoid arthritis caused the increase of cardiovascular risk factors, or if the risk factors were there before arthritis onset. To do this, they conducted an observational study on over five hundred patients positive for either the rheumatoid factor or ACPA (both indicators of a high risk of rheumatoid arthritis). The goal was to follow common cardiovascular risk factors in the group over five years and identify any correlations.
They found that there were two subtle but significant differences in patients with and without a high risk of developing rheumatoid arthritis. Rheumatoid arthritis patients had a higher heart rate, and lower lipid levels, both of which were risk factors of cardiovascular disease. Classical cardiovascular risk scores did not significantly differ between the two groups, which the team notes could be due to the lack of modern risk indicators involved in their calculations.
Observational studies do not usually reveal incredibly impactful information but can help identify trends and possible opportunities for further investigation. This study identified that two cardiovascular risk factors, heart rate, and lipid levels, were present in many patients with a high risk of developing rheumatoid arthritis before its actual onset. The study could not elaborate on possible reasons why, but never-the-less show that there might be a relationship between rheumatoid arthritis and cardiovascular disease, beyond the apparent symptoms.
The study concludes, “Our results suggest that changes in serum lipid profile and heartrate commence prior to RA diagnosis and that ACPAs might be involved in the link between immune mechanisms, inflammation and lipid metabolism changes.”
Sources: PLOS One, Mayo Clinic, Arthritis Research Canada