What is High Sensitivity C-reactive Protein (HS-CRP)?
Inflammation (swelling) of the arteries is a risk factor for cardiovascular disease. It has been linked to an increased risk of heart disease, heart attack, sudden death, stroke, and peripheral arterial disease. It has also been linked to an increased risk of restenosis, or the re-closing of an artery that has been treated with balloon angioplasty.
High Sensitivity (also called Ultra-sensitive) C-reactive protein is known as HS-CRP, US-CRP or CRP for short. It is a protein found in the blood and what we call a "marker" for inflammation, meaning its presence indicates a heightened state of inflammation in the body. Inflammation is a normal response to many physical states including fever, injury and infection. Inflammation plays a role in the initiation and progression of cardiovascular disease.
CRP and Cardiovascular Risk
In studies involving large numbers of patients, CRP levels seem to be correlated with levels of cardiac risk. In fact, CRP seems to be at least as predictive of cardiac risk as cholesterol levels. The Physicians Health Study, a clinical trial involving 18,000 apparently healthy physicians, was the first large study to show that elevated levels of CRP were associated with a threefold increase in the risk of heart attack.
In the Harvard Women's Health Study, results of the CRP test were more accurate than cholesterol levels in predicting coronary problems. Twelve different markers of inflammation were studied in healthy, postmenopausal women. After three years, CRP was the strongest predictor of risk. Women in the group with the highest CRP levels were more than four times as likely to have died from coronary disease, or suffered a nonfatal heart attack or stroke. This group was also more likely to have required a cardiac procedure such as angioplasty or bypass surgery than women in the group with the lowest levels.
More recently, the JUPITER (Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin) study has shown that statins prevent heart disease and lower risks of stroke, heart attack - and death – in individuals with normal levels of LDL (the bad cholesterol), but elevated levels of “high-sensitivity C-reactive protein” or CRP.
How can I be tested?
A simple blood test can be done at the same time as a cholesterol screening. The high-sensitivity C-reactive protein (HS-CRP) test, helps determine heart disease risk and is widely available. Patients should ask their doctors about HS-CRP specifically.
The American Heart Association recommends HS-CRP as part of routine screening for those who are at intermediate risk for heart disease. The Cleveland Clinic has used the hs-CRP test routinely for at-risk patients for several years. It is a useful test for people with one or two risk factors who wonder if they are at risk of heart attack or stroke. The JUPITER study results suggest that people even with minimal risk factors in an older age group (late 50s to early 60s) should have their CRP tested and treated accordingly.
Ultra Sensitive C-Reactive Protein Blood (HS-CRP)
- C-reactive protein measures an inflammatory response in the body and has been shown to play a role in atherosclerosis and blood clot formation.
- Patients should ask their doctor specifically about hs-CRP, as this test helps determine heart disease risk. Elevated HS-CRP is related to increased risk for heart attack, restenosis of coronary arteries after angioplasty, stroke, and peripheral vascular disease (PVD).
- While elevated cholesterol, LDL and triglycerides and low HDL are all independent risk factors for heart disease and cholesterol build-up, HS-CRP provides additional information about inflammation in the arteries – something not determined by lipid testing alone.
Results:
- Less than 1.0 mg/L = Low Risk for CVD
- 1.0 – 2.9 mg/L = Intermediate Risk for CVD
- Greater than 3.0 mg/L High Risk for CVD
Readings of 50 and above are possible, but we generally attribute a level higher than 10 to inflammation due to other conditions, such as an infection, illness, or a serious flare-up of arthritis, can raise CRP levels.
Therefore, testing should not occur while ill or injured. The HS-CRP should be ordered to evaluate CVD risk in apparently healthy individuals who have not had recent infection or other serious illness. Those who have levels of higher than 10 should be evaluated for other sources of inflammation.
Preparation:
This test may be measured any time of the day without fasting.
What can I do if my HS-CRP level is high?
A high HS-CRP should be treated by aggressive risk factor reducing strategies. These include lifestyle change, such as:
- Eating a heart-healthy diet
- Reducing high cholesterol levels
- Maintaining a healthy weight
- Exercising regularly
- Managing diabetes and high blood pressure
- Quitting smoking or tobacco use
- Drinking less alcohol
Cholesterol-lowering statin drugs both reduce CRP and LDL and lower cardiac risks. Antithrombotic medications such as low dose aspirin or clopidogrel may provide protection as well. Your doctor will prescribe the correct medications and dosage to treat your condition.
HS-CRP: Improve Your Cardiovascular Health
HS-CRP, combined with a global risk evaluation can provide an overall view of cardiovascular risk. This information is important to develop a plan to improve your cardiovascular health. Call the Preventive Cardiology and Rehabilitation Program at 216.444.9353 or toll-free 800.223.2273, ext. 49353 to be evaluated and get started.
For More Information
Reviewed by Dr. Leslie Cho, Director of the Cleveland Clinic’s Women’s Cardiovascular Center and Section Head, Preventive Cardiology and Rehabilitation at the Miller Family Heart & Vascular Institute at Cleveland Clinic.
Reviewed: 06/10
This information is about testing and procedures and may include instructions specific to Cleveland Clinic.
Please consult your physician for information pertaining to your testing.
This information is provided by Cleveland Clinic and is not intended to replace
the medical advice of your doctor or health care provider.
Please consult your health care provider for advice about a specific medical condition.
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