Derek Burnett
Derek Burnett is a Contributing Writer at Bottom Line Personal, where he writes frequently on health and wellness. He is also a contributing editor with Reader’s Digest magazine.
Rheumatoid arthritis (RA) is a devastating disease afflicting more than a million Americans. It occurs when the body is betrayed by its own immune system, which attacks healthy tissues in the joints by bombarding them with inflammatory substances. But there’s evidence to suggest that people with RA have something else to worry about…an increased risk of developing heart disease. What is the connection, if any, between these two conditions? And if RA really puts you at risk of heart disease, can controlling your RA lower your risk of heart problems?
For reasons we don’t fully understand, something goes haywire in the immune systems of people with RA. One of the immune system’s strongest assets is its zero-tolerance policy toward pathogens. Once it recognizes a substance as a threat, it holds a grudge against it for decades, having memorized its features and essentially sworn to destroy it on sight. In RA and more than 100 other diseases that we categorize as autoimmune disorders, the immune system has mistakenly learned to hold such a grudge against the body’s own healthy tissues. In multiple sclerosis, it’s the cells of the central nervous system that get attacked. In psoriasis, it’s the skin. In RA, it’s the joints of the fingers, wrists, toes, elbows, knees, feet, and ankles.
The disease process begins when inflammatory cells, especially cytokines, invade the joint-encasing tissue called the synovium. The inflammation brings about structural changes to this tissue, causing it to proliferate and form a coarse structure called a pannus, which begins to deform the joint. Now a cycle of inflammation gets under way, with the cells of the pannus releasing more inflammatory compounds that start to eat away at the surrounding cartilage and bone. Even the ligaments, tendons, and the joint capsules themselves may become inflamed and suffer damage as the disease proceeds symmetrically on both sides of the body. If left untreated, the joints can become unstable, misshapen, painful, and even unusable.
But untreated RA doesn’t limit itself to the joints. The inflammation spreads throughout the body, causing damage to organs and tissues far from any joint. It can cause the formation of scar tissue in the lungs, the stiffening of the lining of the heart, neurological damage, and vision problems.
For many years, scientists understood that one of the main features of cardiovascular disease was a narrowing of the arteries due to the buildup of fatty substances, a condition known as atherosclerosis. As the thinking went, a poor diet and lack of exercise allowed fats to accumulate along the inner walls of the blood vessels. Like rust buildup inside a water pipe, this caused the passageway inside the artery to narrow, forcing the heart to pump harder, causing blockages that trigger heart attacks, and allowing the formation of blood clots which can break free and cause ischemic strokes.
But in recent decades, our understanding of cardiovascular disease has become more sophisticated as mounting research has pointed toward inflammation as being an important part of the disease process. We’re still not completely sure of the exact role inflammation plays in heart disease, but it’s clear that chronic inflammation is a significant risk factor for the condition. Scientists think inflammation could be involved in both the development and worsening of cardiovascular disease. Here’s how that might work.
In the bodies of people living with chronically elevated levels of inflammation, the blood vessels are constantly exposed to inflammatory cells that use the circulatory system as the transport method to reach the tissues they’re targeting. The arteries are not immune to the effects of these inflammatory cells, and their linings begin to develop nicks, bumps, and other irregularities. Now when fatty substances come through the arteries, the arterial surface is no longer smooth, and the fats begin to collect in the surface irregularities of the arterial walls. The immune system recognizes those fatty plaques as threats and sends in more inflammatory enzymes and cells to wall them off and keep them from contaminating the bloodstream, similarly to how an abscess might form to wall off an infection in the mouth. But that makes the plaque even larger and more likely to form blockages. And sometimes the entire plaque structure, with its added cells and enzymes, bursts and travels downstream where it can cause a stroke.
It’s not hard to piece together a theory whereby the elevated inflammation levels of someone living with rheumatoid arthritis increases their risk of cardiovascular disease through the mechanisms just described. After all, it’s not just RA that’s associated with higher risk of heart disease, but numerous other autoimmune disorders marked by chronic inflammation, including irritable bowel disease, lupus, and psoriasis. In fact, people with these disorders tend to experience heart disease about a decade earlier than the general population. However, we still don’t know enough to say with certainty that RA or any other autoimmune disorder causes heart disease or even predisposes people to it, only that the two conditions are closely associated. There could be, for example, genetic or even lifestyle factors that make someone more susceptible both to rheumatoid arthritis and to cardiovascular disease.
The good news for people living with RA is that taking steps to protect their joints appears to be protective of their hearts, as well. Methotrexate, the most commonly prescribed medication for RA, has been shown to keep cardiovascular disease from progressing, as well as to lower the overall risk of death from heart disease.
But RA patients with high blood pressure, elevated cholesterol, or known heart disease…or who are known to be at increased risk of heart disease…should be cautious about using non-steroidal anti-inflammatory drugs (NSAIDs) to control inflammation and reduce pain. These medications, which include ibuprofen (Advil) and naproxen sodium (Aleve), have been associated in studies with increased risk of high blood pressure, heart attack, and stroke. The decision of whether or not to take them should be made in careful consultation with a physician.
