hs-CRP and homocysteine measure different substances. High-sensitivity C-reactive protein, or hs-CRP, is used in some cardiovascular risk assessments. Homocysteine can contribute to an investigation of vitamin-related or other health concerns.[1][2]

What hs-CRP measures

C-reactive protein is produced by the liver in response to inflammation. The high-sensitivity test detects smaller amounts than a standard CRP test and can add information about cardiovascular risk.[1]

A raised result does not show where inflammation is occurring or what caused it. The interpretation considers symptoms, history, other results, and possible temporary causes.

The American Heart Association describes hs-CRP as a possible additional test when it would help clarify an existing cardiovascular risk assessment.[3]

What homocysteine measures

Homocysteine is an amino acid processed with the help of B vitamins, including B12 and folate. Levels can rise with vitamin deficiencies, kidney disease, hypothyroidism, and other factors.[2]

MedlinePlus notes that routine homocysteine screening for heart-disease risk is not recommended for everyone. Lowering the measurement has generally not been shown to reduce heart attacks or strokes in most settings.[2]

Decide what question needs answering

If the concern is cardiovascular risk, blood pressure, cholesterol, glucose, history, and other established factors come into the assessment. If the concern is fatigue or a possible deficiency, the symptoms may suggest a different investigation.