How do I Compare CRP & LDL?

Researchers have found that high amounts of certain substances in the blood are linked with certain negative cardiovascular events such as heart attack and stroke. Doctors often send patients to have blood drawn so that these substances can be measured and risk level--or response to efforts to lower them--can be assessed. Two important indicators in the blood are low-density lipoprotein (LDL) cholesterol and c-reactive protein (CRP) or high-sensitivity c-reactive protein (hsCRP). For a patient to be considered at low risk for adverse heart events, both of these numbers should be low.

Things You'll Need

• Previous CRP and LDL results (if available)

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Instructions

• 1

  The blood work analysis results will be sent to your doctor's office.

  Get your blood work done. Your doctor will convey to the laboratory exactly how much blood to take and what it should measure in the blood it draws. You may be instructed to "fast" overnight or for several hours before the blood is taken. After your blood is drawn, the samples will be sent to a special lab for analysis.

• 2

  Obtain a copy of your blood work results. Your doctor will receive the results in a matter of days and share them with you. He may simply tell you that the numbers are low, normal or high. If you do not receive a written report, request a copy from your doctor's office for your records.

• 3

  Look at the LDL number. LDLs are large molecules in the blood that can cling to artery walls, leading to blockage of these important passageways. LDL cholesterol is measured in milligrams per deciliter, or mg/dL. According to a National Institutes of Health and National Heart Lung and Blood Institute pamphlet, 100 mg/dL or lower is optimal; 100 to 129 is near optimal/above optimal; 130 to 159 is borderline high; 160 to 189 is high and 190 or more is very high. As you compare older lab results to newer ones, your LDL number should be lower each time until it is in the optimal range.

• 4

  Look at the CRP number. CRP is produced by the liver and indicates inflammation when found in blood. This could be due to trauma or infections, but researchers think CRP also may be high in blood when someone has atherosclerosis, which is clogging in the arteries and a big warning sign. When CRP is low in blood, probably fewer cells stick together and form plaque in arteries. In a 2008 study funded by AstraZeneca, healthy subjects whose CRP and LDL were lowered were less likely to have heart attacks or strokes than their counterparts. Therefore, a low CRP number is considered good. CRP is measured in milligrams per liter of blood, or mg/L. According to the American Heart Association and U.S. Centers for Disease Control and Prevention, under 1 mg/L translates to a low risk; 1 to 3 is average risk; and above 3 is high risk.

  If this is your first blood test for CRP, expect to have another one in the near future to compare the numbers and see if they have gone down in response to medicine or lifestyle changes. As with LDL, the goal is to bring the numbers down until they are in low-risk range.