What is the purpose of a high sensitivity C-Reactive Protein (CRP) test?

From the Guidelines

The primary purpose of a high sensitivity C-Reactive Protein (CRP) test is to assess cardiovascular disease risk, particularly in patients with intermediate risk factors, as an independent marker of risk that may help direct further evaluation and therapy in the primary prevention of CVD. The hsCRP test is used to measure low levels of inflammation in the body, which can detect smaller amounts of CRP in the blood, unlike standard CRP tests that detect higher inflammation levels 1. This test is valuable for identifying individuals who may be at risk for heart disease or stroke despite having normal cholesterol levels, with levels below 1 mg/L indicating low cardiovascular risk, 1-3 mg/L suggesting moderate risk, and above 3 mg/L suggesting high risk. Some key points to consider when using the hsCRP test include:

• hsCRP is an independent marker of risk that may be used at the discretion of the physician in patients judged by global risk assessment to be at intermediate risk for cardiovascular disease (CVD) 1
• hsCRP levels may be useful in motivating patients to improve their lifestyle behaviors, although the benefits of this strategy remain uncertain 1
• Patients with persistently unexplained marked elevation of hsCRP after repeated testing should be evaluated for noncardiovascular causes 1
• The test is particularly useful for patients with intermediate risk factors for cardiovascular disease, helping physicians make decisions about preventive treatments like statins. It's also important to note that inflammation plays a key role in atherosclerosis development, as inflammatory processes contribute to plaque formation and instability in blood vessels 1. For accurate results, patients should avoid exercise, smoking, and taking certain medications before the test, as these factors can temporarily elevate CRP levels. Overall, the hsCRP test is a valuable tool for assessing cardiovascular disease risk and guiding treatment decisions, particularly in patients with intermediate risk factors.

From the Research

Purpose of High Sensitivity C-Reactive Protein (CRP) Test

The purpose of a high sensitivity C-Reactive Protein (CRP) test is to:

• Assess cardiovascular risk and predict the likelihood of cardiovascular events, such as heart attacks and strokes 2, 3, 4, 5, 6
• Identify individuals with residual inflammatory risk, which is associated with an increased risk of major adverse cardiovascular events, cardiovascular mortality, and all-cause mortality 3
• Monitor the effectiveness of statin therapy and other interventions in reducing inflammation and cardiovascular risk 2, 4, 5
• Provide additional information for cardiovascular risk assessment, beyond traditional risk factors such as lipid screening and global risk assessment 2, 4, 5

Key Findings

• High-sensitivity CRP (hs-CRP) is a stronger predictor of cardiovascular events and death than low-density lipoprotein cholesterol (LDL-C) in patients receiving statin therapy 3
• Elevated hs-CRP levels are associated with an increased risk of cardiovascular events, cardiovascular mortality, and all-cause mortality, even in individuals with normal LDL-C levels 3, 5
• Statin therapy can lower hs-CRP levels and reduce the risk of cardiovascular events, even in individuals with normal LDL-C levels 4, 5

Clinical Applications

• High-sensitivity CRP testing can be used to:
  • Identify individuals at high risk of cardiovascular events who may benefit from statin therapy or other interventions 2, 4, 5
  • Monitor the effectiveness of treatment and adjust therapy as needed 2, 4, 5
  • Provide additional information for cardiovascular risk assessment and management 2, 4, 5