Gene Links Rheumatoid Arthritis And Cardiovascular Disease

A recent study in the United Kingdom has isolated a gene combination that causes people with rheumatoid arthritis to be as much as three times more likely to die prematurely from cardiovascular disease.

The study which was funded by the Arthritis Research Campaign and led by Dr. Tracey M. Farragher at the University of Manchester involved over 1,000 individuals with arthritis. At the conclusion of the study 242 of the patients had died with cardiovascular disease responsible for just under a third of the deaths.

The researchers found that individuals with a particular combination of a gene called HLA-DRB1, which is associated with an increased risk of developing rheumatoid arthritis, were three times more likely to develop cardiovascular disease than those without the gene combination. Furthermore their appeared to be interactions between the gene combination and smoking that increased the risk of cardiovascular disease even further. Individuals with the high risk gene combination who also had anti-CCP antibodies (antibodies directed against the bodies own proteins that are found in most, but not all RA sufferers), and who currently smoked were a massive 7.81 times more likely to die from cardiovascular disease.

According to Professor Alan Silman, who was involved in the research “We have known for some time that smoking is a major risk factor for developing rheumatoid arthritis, but this study confirms that rheumatoid arthritis patients with this particular genetic variant who continue to smoke are putting themselves in considerable danger of life-threatening cardiovascular disease.”

The inflammation associated with rheumatoid arthritis is thought to be associated with atherosclerosis (hardening of the arteries) which increases the likelihood of an individual suffering a heart attack or stroke. It is also possible that decreased exercise seen in individuals suffering from arthritis may also be responsible for increasing cardiovascular risk.

The research is reported in issue two of the February 2008 edition of “Arthritis & Rheumatism”, a peer reviewed journal of the American College of Rheumatology.

Previous studies have found a 2 to 3-fold increase in the risk of cardiovascular disease, even after adjustment for known cardiovascular risk factors. A 2003 study, involving 114,342 from the Nurses Health Study (NHS), and published in the journal Circulation, found that women who had been diagnosed with rheumatoid arthritis had 2.07 and 1.47 times the risk of suffering a heart attack or stroke respectively than women free of rheumatoid arthritis.

While the women suffering from arthritis had marginally decreased physical activity, increased rates of hypertension, and were less likely to have never smoked, adjustment for these and other cardiovascular risk factors made little difference to the results. Cardiovascular risk was also linked to the duration of rheumatoid arthritis with women suffering from the disease for at least 10 years 3.1 times more likely to suffer a myocardial infarction.