Rheumatoid arthritis patients at higher risk for unrecognized heart disease and cardiac sudden death

People with rheumatoid arthritis not only have a higher risk of coronary heart disease than those in the general population, but they have more silent, unrecognized heart attacks and sudden cardiac deaths, according to a Mayo Clinic study published in the February issue of Arthritis & Rheumatism. They are also much less likely to complain of chest pain.

The increased heart disease risk may be present even before the diagnosis of rheumatoid arthritis, according to the researchers.

During the two years before diagnosis of rheumatoid arthritis, patients with this disease were three times more likely to have been hospitalized for an acute heart attack and five times more likely to have an unrecognized heart attack. They were also less likely to have had a history of chest pain, compared to those without rheumatoid arthritis. After their diagnosis, the rheumatoid arthritis patients were twice as likely to experience unrecognized heart attacks and sudden cardiac deaths.

Hilal Maradit Kremers, M.D., lead study investigator and research associate in the Mayo Clinic Department of Health Sciences Research, says the study suggests three major messages for rheumatoid arthritis patients:

- The risk of heart attack is already there at the time a rheumatoid arthritis diagnosis is first made.

- Heart disease can remain silent in those with rheumatoid arthritis. Regular cardiac checkups are important, as is lowering traditional cardiac risk factors, such as taking care of blood pressure and cholesterol and quitting smoking.

- Heart disease in rheumatoid arthritis patients can manifest for the first time as a cardiac sudden death.

The researchers were surprised to find that the increased cardiac events in rheumatoid arthritis patients could not be explained by an increase in traditional heart disease risk factors such as elevated cholesterol, blood pressure and body mass index, diabetes, and alcohol abuse, indicates Dr. Maradit Kremers.

"What we are finding is that though traditional cardiovascular risk factors are important, they are less important for those with rheumatoid arthritis," says Dr. Maradit Kremers. "Something else is going on. It could be that rheumatoid arthritis and heart disease have a common origin. What we do know is that the cause cannot be explained by just one factor. It is multifactorial."

To date, there also is no definitive information for rheumatoid arthritis patients about steps they can take to avoid heart disease, according to the Mayo Clinic researchers. Meanwhile, they indicate that it is critical that rheumatoid arthritis patients recognize their risks for heart disease and that they seek medical care for any cardiac symptoms or complaints.

Dr. Maradit Kremers explains that the silent heart attacks found in the study usually were detected when the rheumatoid arthritis patient saw a physician for some other reason and an electrocardiogram was ordered, revealing a past heart attack. "It's possible that people suffering from rheumatoid arthritis have so much pain in their joints and are receiving so many painkillers that they either don't feel the chest pain in the same way as those without rheumatoid arthritis or don't appreciate its importance," she says.