Tests and Procedures

C-reactive protein test

Results

It can take a few days to get your results. Your doctor will explain to you what the results of your test mean.

CRP is measured in milligrams per liter (mg/L). Results for a standard CRP test are usually given as follows:

  • Normal: Less than 10 mg/L
  • High: Equal to or greater than 10 mg/L

Note: Abnormal range values may vary depending on the laboratory doing the test. A high CRP test result is a sign of acute inflammation. It may be due to serious infection, injury or chronic disease. Your doctor will recommend other tests to determine the cause.

Results for an hs-CRP test are usually given as follows:

  • Lower risk of heart disease: hs-CRP level less than 2.0 mg/L
  • Higher risk of heart disease: hs-CRP level equal to or greater than 2.0 mg/L

A person's CRP levels vary over time. A coronary artery disease risk assessment should be based on the average of two hs-CRP tests, ideally taken two weeks apart. Values above 2.0 mg/L may reflect an increased risk of heart attacks or risk of a recurrent heart attack.

Remember that your hs-CRP level is only one risk factor for coronary artery disease. If you have a high hs-CRP level, it doesn't definitely mean you have an overall higher risk of developing heart disease. Other tests need to be done to further evaluate your risk.

Talk to your doctor about all your risk factors and ways you can try to prevent coronary artery disease and a heart attack. Your doctor might recommend lifestyle changes or medications to decrease your risk of a heart attack.