I s it a new era in the war against heart attacks and stroke?
For many years, researchers focused on cholesterol in reducing the risk of cardiovascular events such stroke and heart attack. In recent years, though, attention has shifted toward inflammation, the body’s first response to injury or infection. It’s what causes cuts to swell, but also happens internally as part of the response to foreign invaders such as viruses and bacteria.
Study results confirm hypothesis
Now, for the first time, researchers say they have evidence of a connection between inflammation, heart attacks and stroke.
In a study published in New England Journal of Medicine, researchers found that heart-attack survivors who were given the anti-inflammatory medicine canakinumab, which has no known effect on cholesterol, reduced the risk of a future heart attack and stroke. For the Canakinumab Anti-inflammatory Thrombosis Outcomes Study (CANTOS), which was sponsored by Novartis Pharmaceuticals, more than 10,000 patients who’d had a heart attack received injections of canakinumab (or a placebo) every three months for four years.
Patients who received the two highest doses of the medicine experienced a 15 percent reduction in the risk of a cardiovascular event – including fatal or non-fatal heart attacks and strokes – compared to patients who received the placebo. The need for interventional procedures, such as bypass surgery and angioplasty, was cut by more than 30 percent.
The research team was led by Dr. Paul Ridker at Brigham and Women’s Hospital in Boston. Dr. John Ijem, a Tidelands Health cardiologist, helped enroll people in the study.
“Even when you’re not having a heart attack, if inflammation is elevated, there is an increased risk of future heart attack or coronary artery disease,” Dr. Ijem said. “If we treat the inflammation process, are we able to get reduction of future coronary events? So far, the answer is yes, but studies are ongoing.”
Factors that influence inflammation
Aging is one reason a patient might have higher levels of inflammation, Dr. Ijem said. Another is genetics, and some infections can also contribute to inflammation.
People who believe they might be at risk for heart attack or heart disease should see a qualified primary care provider, Dr. Ijem said. The physician will take a history and determine risks, such as diabetes, high cholesterol, sedentary lifestyle, smoking and genetic predisposition, he said.
The physician can order blood tests to determine inflammation levels, he said. Patients with high levels of inflammation may one day be prescribed medicines like canakinumab, which is not yet approved for treating heart conditions.
Ridker said anti-inflammatories are the most important breakthrough since doctors were able to link heart disease to lifestyle and high cholesterol.
Half of heart attacks occur in people who do not have high cholesterol, he said. Anti-inflammatory medicines may be the key to reducing their risk.
“In my lifetime, I’ve gotten to see three broad eras of preventative cardiology,” he said. “In the first, we recognized the importance of diet, exercise and smoking cessation. In the second, we saw the tremendous value of lipid-lowering medicines such as statins. Now, we’re cracking the door open on the third era. This is very exciting.”