Many of the effects of rheumatoid arthritis are overt and difficult to ignore, including aching; tender, swollen joints; fatigue; weight loss; muscle weakness and fever. Other side effects may continue silently for years, causing damage that may not be evident until it reaches a crisis.

This may be especially true for rheumatoid arthritis and heart disease.

Most of us are aware that heart disease is the No. 1 killer of American men and women. What you may not know is that it is also a cause of premature death in more than 50 percent of people with RA.

According to New York rheumatologist Dr. Jon T. Giles, “RA patients have higher rates of heart attacks, strokes, sudden cardiac death and heart failure compared with otherwise similar people without RA.”

“Just like in the general population, not everyone with RA will have clinical heart disease,” says Giles, who is an associate professor of medicine in the Division of Rheumatology at the College of Physicians & Surgeons at Columbia University. “However, they are more prone to heart disease.”

In addition, the heart disease seen in people with rheumatoid arthritis is different. “[It] is more likely to be subclinical, meaning clinically silent,” according to Giles.

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Atherosclerosis, or hardening of the arteries, also progresses faster in people with RA, and the type of atherosclerotic plaques — the buildup of fat, cholesterol, calcium and other substances that clog blood vessels in the heart and brain — have different characteristics “that make them more unstable and prone to rupture, which is the event that leads to a heart attack,” Giles says.

“The arteries of an RA patient may effectively be ‘older’ than their chronological age,” he adds.

To further complicate matters, Giles indicates there is also some suggestion that individuals with rheumatoid arthritis who have very low levels of low-density lipoproteins — LDL, the so-called “bad cholesterol” — are actually at higher risk for heart disease. “This is probably because systemic inflammation actually lowers LDL levels in the blood and may give the RA patient a false sense of security that if their ‘bad cholesterol’ is low, then they are protected from risk,” he explains.

According to Giles, the reasons for the increased risk of heart disease in individuals with RA are not completely known. “In general, RA patients don’t have higher rates of the most common risk factors for heart disease, such as high blood pressure, high cholesterol or diabetes, so these features don’t help explain the higher rates.”

This can make it difficult to predict which individuals with rheumatoid arthritis will get the disease.

The intrinsic inflammatory nature of RA may be to blame, at least in part. Rheumatoid arthritis is an incurable, autoimmune disease characterized by chronic inflammation that attacks the joints and many other tissues in the body, including the eyes, kidneys, lungs and heart.

“The mechanisms that explain this link [between RA and heart disease] are really still being actively explored,” says Dr. Ted R. Mikuls, a rheumatologist in Omaha, Nebraska.

“Cardiovascular disease is not only increased in RA but also in other diseases [such as lupus] that are also characterized by chronic systemic inflammation. So, a prevailing thought has been that systemic inflammation adversely influences cardiovascular risk through either direct detrimental effects on blood vessels or possibly indirectly by impacting other risk factors,” says Mikuls, who is the Umbach Professor of Rheumatology in the Division of Rheumatology & Immunology, Department of Internal Medicine, at the University of Nebraska Medical Center and VA Nebraska-Western Iowa Health Care System.

Inflammatory proteins, called cytokines, which are produced by immune cells in people with rheumatoid arthritis, are known to be part of the mechanism that leads to atherosclerosis in everyone.

“Other diseases that are associated with high levels of cytokines also tend to have more atherosclerosis and higher rates of cardiovascular disease events,” Giles notes.

“However, this may not be the only contributor, since some of the autoimmune features of RA, like the autoantibodies that are made by RA patients, and the particular way that certain types of immune cells become activated in RA, may also add to the risk in a way that is more than can be explained by cytokines alone,” he says.

It could also be that both rheumatoid arthritis and heart disease share a common trigger.

“There are striking parallels between the immune cell types present [in both diseases] and in how they behave in the inflamed joint lining of people with RA and the inflamed atherosclerotic plaque of anyone [with or without RA],” according to Giles.

And both diseases have high levels of macrophages, a type of cell that “gives rise to an array of inflammatory cytokines, many of which are the therapeutic targets of many RA treatments,” Giles adds.

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If you have rheumatoid arthritis, the outlook is not all bad.

“Thankfully, heart disease is not an inevitable consequence of having RA and the risk appears to be ‘modifiable,'” Mikuls says. “We have found that there is a robust relationship between RA disease activity and mortality risk related to heart disease — the more active the RA, the stronger the risk.”

The good news is that this increased risk appears to disappear when rheumatoid arthritis is well-controlled, “suggesting that tight arthritis control imparts important dividends in terms of heart health for patients with RA,” Mikuls adds.

Giles agrees. “There is solid evidence from observational studies that controlling RA inflammation reduces cardiovascular risk in RA. It is unclear whether this can be accomplished with any RA medication that reduces inflammation, or whether certain RA medications have more protective effect. The best data for a special protective effect are for methotrexate,” he says.

“Methotrexate is considered a ‘cornerstone’ treatment in RA and appears to be quite cardioprotective — to the point that it is being actively studied now as a means of preventing cardiovascular disease progression in individuals without RA,” Mikuls says.

“Some medicines used in arthritis treatment, however, such as glucocorticoids and non-steroidal anti-inflammatory drugs, might actually increase the risk of heart disease, so caution with these drugs in at-risk patients is appropriate. More research is needed to better understand the precise relationship of other RA drugs [and drug combinations] with the progression of cardiovascular disease in our patients,” Mikuls adds.

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Giles lists three main things that you should do if you have rheumatoid arthritis to reduce your risk of heart disease.

First, “talk to your rheumatologist about your risk and how and when you should be screened for heart disease,” he says. If your rheumatologist doesn’t suggest such screening, bring the subject up yourself. “This is where you can be proactive if it has not been addressed.”

Second, “work hard to obtain maximum control of standard risk factors [for heart disease]. Stop smoking, ensure that blood pressure is controlled, get diabetes under control, exercise, maintain a heart-healthy diet and take cholesterol-lowering medication if cholesterol levels are elevated.”

Third, “get RA symptoms under control with RA medications.”

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What’s the Connection Between Rheumatoid Arthritis and Heart Disease? originally appeared on usnews.com