Researchers believe that chronic inflammation initiates and speeds along the process of atherosclerosis. How does inflammation damage your body and how can you detect it? Read on …
When you read or hear the word "inflammation,” what comes to mind? An infected cut or scrape? Swollen, congested sinuses? Painful, arthritic joints? What about coronary heart disease? It probably wasn’t on the list. Yet a large amount of research shows that inflammation plays a role -- possibly a major one -- in the development and progression of atherosclerosis, the buildup of fatty plaques that leads to coronary heart disease, heart attacks, and strokes.
The inflammation we are talking about is not the short-term kind that the immune system produces to help the body fight an acute infection or heal a wound. Instead, it is low grade and chronic inflammation -- present in the body at low levels day in and day out.
The inflammation - atherosclerosis story begins with risk factors: high blood pressure, high cholesterol, obesity, and smoking. These risk factors irritate and disturb the normal biology and activity of the arteries. This irritation in turn stimulates the production of cells and proteins that initiate and fuel inflammation.
Ongoing irritation and inflammation by these risk factors eventually injures the delicate tissues of the arteries. This injury stimulates the production of more inflammatory factors and attracts immune-system cells called monocytes that burrow into the arteries where they develop into other cells known as macrophages. Macrophages absorb cholesterol that enters the injured artery. As the cholesterol accumulates, the macrophages are transformed into foam cells, the earliest stage of plaques.
As plaque builds up inside an artery, inflammatory factors make the plaque unstable and prone to rupture or cracking. When a plaque becomes disrupted, its contents may spill into the bloodstream and come into contact with platelets and clotting factors that can produce a blood clot and ultimately a heart attack.
Detecting Inflammation -- Unfortunately, there are no outward signs that inflammation is damaging arteries. That’s why researchers have developed blood tests to measure substances in the blood that signal inflammation. The most widely known and commonly used is C-reactive protein (often abbreviated as CRP). CRP levels rise and fall with the intensity of inflammation in the body -- whether the inflammation involves the arteries or some other inflammatory disease such as rheumatoid arthritis.
Studies clearly show that elevated CRP levels are associated with an increased risk of heart attack or dying of heart disease. In fact, one study found that CRP was just as good a predictor of risk as LDL cholesterol. In addition, evidence is emerging that lowering high CRP levels can reduce future heart attacks in people who are at high risk. A high CRP level is 3 mg/L or above; the optimal level is less than 1 mg/L.
