C-REACTIVE PROTEIN AND YOUR HEART



CRP or C – Reactive Protein is a protein released by the liver during periods of active inflammation in the body. Very likely, you have already learned about this important protein in the news media, since it has been extensively publicized.

The importance of CRP has to do with the fact that it is an independent risk factor for the development of heart disease and stroke. Although we already know about such things as high blood pressure, smoking, diabetes, elevated cholesterol and a strong family history of heart disease as being risk factors, the CRP also increases this risk, independently. In fact, in men very high levels of CRP (also known as hs-CRP, or high-sensitivity CRP) result in a three-fold increase in the risk of heart attack, and a two-fold increase in the risk of stroke.

How does the CRP relate to an increased risk of cardiovascular events such as stroke and heart attack? The process of inflammation, by which the body is able to respond effectively to injury or infection, is also involved in the process of atherosclerosis, or progressive hardening of the arteries. In this situation, LDL or low density lipoprotein cholesterol…the “bad cholesterol"…as well as other substances, build up within the walls of arteries, especially around the heart and to the brain and result in plaques, which eventually can rupture, form a clot directly in the artery, and completely block the flow in the artery beyond the plaque. If this occurs in an artery around the heart, a “heart attack” occurs; if it occurs in an artery in the neck, a “stroke” can occur.

Interestingly the Women’s Health Study, a major study of 28,000 women over an 8-year period, concluded that CRP levels were even more predictive of vascular events (strokes and heart attacks) than the LDL levels. Furthermore, the highest risk for these women occurred in those with elevated levels of both CRP and LDL cholesterol.

Whenever the inflammatory response is activated in the body, CRP is released in significant quantities from the liver and aids this inflammatory response. And, since the hardening of the arteries process involves an activation of the inflammatory system, it can result in elevations of the blood levels of C RP, which can now be measured in laboratories. Thus, if a person is otherwise free of an obvious injury or infection, then an elevated C RP level is likely to represent an active process of hardening of the arteries in the body, and places the person at higher risk for future stroke or heart attack.

As you probably know, aspirin is beneficial for people with atherosclerosis; some of its benefit is probably related to reducing the inflammatory process, as well as to thinning the blood, since its benefits are seen to be greatest in those with the highest levels of underlying inflammation. In fact, it is thought that the inflammatory response to some ordinary bacteria and viruses may lead to initiating and/or aggravating the hardening of the arteries process, almost like an “innocent bystander” approach.

You may wonder what other treatments may be available to control damage to the arteries via the inflammatory process. Presently, there are no definite medications that are specifically approved for the lowering of CRP levels. It is not yet possible to directly lower CRP levels significantly with medications, even though some of the current cholesterol medications may do so to a mild degree. Currently the best approach to a patient with an elevated CRP level may be to be even more aggressive in controlling all of their risk factors and getting their cholesterol levels even lower than usual.

Who should have their CRP level checked? Probably those individuals who already have some modest risk for hardening of the arteries, such as people with one or two of the major risk factors mentioned above. At Sacramento Heart and Vascular Medical Associates, CRP tests are available in our laboratory, along with other innovative tests to look for atherosclerosis, such as Coronary Artery Calcium Scoring. An effective diagnostic and treatment strategy can be put into place by any of the Cardiologists at Sacramento Heart & Vascular Medical Associates.

Dan Van Hamersveld, MD, FACC is affiliated with the Sacramento Heart & Vascular Medical Associates located in the Sacramento Heart Center. For more information about the Sacramento Heart & Vascular Medical Associates, visit their website at www.sacheart.com or call (916) 830-2000 and request information be mailed to you. Please address your cardiology-related questions to "Ask the Cardiologist", 500 University Avenue, Sacramento, CA 95825. Selected questions will be answered in future columns.