What Is the Connection between CRP and Inflammation?

C-reactive protein (CRP) is a natural, molecular substance produced by the body that may be evaluated to detect the presence of inflammation. Individuals exhibiting moderate to high amounts of C-reactive protein, as measured with a C-reactive protein test, likely have some degree of inflammation or infection in their system. The connection between CRP and inflammation is often indicative of an inflammatory condition, such as rheumatoid arthritis, but may also serve as a means for monitoring and measuring disease progression.

Originating in the liver, C-reactive protein maintains a constant, subtle presence in the blood. Considered a key element for maintaining healthy immunity, CRP levels are generally influenced by lifestyle and heredity and vary by individual. Individuals with a diagnosis of liver failure experience a significant impairment in CRP production, which can adversely affect the body’s ability to ward off infection and fight inflammation.

The production of C-reactive protein often depends on the body’s overall condition and ability to function. Under normal circumstances, a blood sample shows no sign of the protein at all. CRP production increases to detectable levels when infection and/or inflammation are present in the body. The severity of infection or inflammation will correspond directly to the amount of CRP produced. It is important to understand that the presence of progressive, chronic conditions, such as atherosclerosis and certain cancers, can initiate a steady increase in CRP and inflammation over the long term.

A C-reactive protein test is a diagnostic tool that requires a blood draw to assess protein levels. The test is also known by the monikers ultra-sensitive CRP (us-CRP) and high-sensitivity CRP (hs-CRP). Regardless of the name used, the test is administered the same with the expectation of acquiring the same result, which is an accurate measurement of C-reactive protein levels in the blood. Obtained from the arm, the blood is housed in a vial and sent for laboratory analysis. The test possesses the same risks as any blood draw, including irritation at the puncture site, bleeding, and infection.

All CRP results are interpreted on a general level. Although result values can vary depending on the laboratory used, elevated CRP levels simply indicate there is inflammation present. Measured in milligrams per deciliter (mg/dL), high CRP levels are usually considered anything above 3 mg/dL. Additional diagnostic testing is often required for individuals with a high CRP reading to determine the source and extent of inflammation.

Several situations may contribute to high CRP and inflammation. In some cases, infection can cause a spike in CRP production and, once the infection is treated, protein levels return to normal. High CRP and inflammation may also be triggered by diabetes, physical trauma, and arterial swelling. It is possible that chronic conditions, including autoimmune diseases such as rheumatoid arthritis (RA), may also cause an elevation in CRP production. Unhealthy lifestyle choices, such as prolonged inactivity and smoking, can contribute to elevated CRP levels.

In recent years, the recognized connection between CRP and inflammation has been used as a guideline to assist with determining one’s risk for cardiovascular disease. Arterial inflammation, understood to be a contributing factor in the development of heart disease, may be detected and monitored with periodic C-reactive protein testing. Smokers, obese individuals, and those with a family history of cardiovascular issues are often encouraged to undergo periodic CRP tests.