Can infection trigger heart disease?
Are you the one who always gets whatever is "going around"? Do you seem to be perpetually fighting off flu-like illnesses or other infections, like gum disease? Based on the discovery that chronic infections are common in people who suffer from heart disease, researchers conducted several studies. The results of the studies, reported recently in the American Heart Journal, showed that certain respiratory and periodontal diseases may have a relationship with cardiovascular conditions of all kinds, including hardening of the arteries, heart attacks, and strokes.
Scientists have found, for example, a similarity between the genes that cause arterial damage and those that cause periodontal disease. Indeed, both heart disease and gum disease share risk factors -- age, gender (male), diabetes, smoking, high cholesterol, high blood pressure, and family history. By extension, then, could periodontal disease be an early indicator of future heart disease? Perhaps. It's an association that hasn't been proven but is currently undergoing careful scrutiny by researchers.
The theory is that chronic infections can cause irritation to the inner lining of your blood vessels. When you have an infection, your white blood cells rush to the area to fight off the "invader." People who are susceptible to chronic infections, however, have "supercharged" white blood cells. Instead of simply doing their job, the cells overreact and secrete substances that damage arterial walls and cause scar tissue to form. Over time, scar tissue and fat may develop into the thick layers of artery-clogging material we call plaque. This plaque can rupture, causing a blood clot that totally blocks blood flow through an artery. The result is a heart attack or stroke, perhaps partially due to years of infection.
Infections linked to heart disease
The following chronic infections may lead to the development of cardiovascular disease:
- Periodontal disease. More than 30 million Americans suffer from periodontal disease, a progressive form of infection of the gums and tissues around the teeth. Scientists theorize that bacterial products from infected gums enter the bloodstream, where they can trigger the formation of arterial plaque. A study of 10,000 Americans followed for more than 14 years found that those with periodontal disease had a 25 percent increased risk of developing coronary heart disease. Men below age 50 with gum disease had a 70 percent greater risk of heart problems. Another study showed that men with the worst gum infections were twice as likely to die of heart disease and three times as likely to suffer stroke than men with less severe gum infections.
- Respiratory infections. Research indicates that persistent respiratory infections, such as chronic bronchitis, are associated with coronary heart disease. One study showed that evidence of past infection from Chlamydia pnemoniae -- a bacteria that causes respiratory illness -- was present in 90 percent of heart-attack victims, compared with only 25 percent of people in the control group.
- Cytomegalovirus. A virus that causes flu-like illness has been detected in the arterial plaque of patients with cardiovascular disease. For patients who have had a heart transplant or balloon dilation of blocked coronary arteries, past infection with cytomegalovirus increases the likelihood that clogged arteries will recur.
Preventing infection
If you are prone to chronic infections or have a family history of periodontal disease, take the following precautions to help prevent infection:
- Keep your teeth and gums healthy by brushing twice and flossing once each day. Schedule a dental checkup and cleaning at least every six months.
- Practice good hygiene, including washing your hands before meals and after using the bathroom.
- Stop smoking. Toxins from tobacco cause both gum disease and heart disease.
- If you have an infection, see your health care provider promptly for treatment.
- Get all recommended immunizations. In the future, vaccines may become available to prevent specific infections linked to heart disease.
Elizabeth Smoots, M.D., F.A.A.F.P., is a board-certified family physician in Seattle, Washington. A fellow of the American Academy of Family Physicians, Dr. Smoots specializes in prevention and primary care medicine.
