High Sensitivity C-Reactive Protein (hs-CRP) Test

Hs-CRP or high-sensitivity C-reactive protein test is a more specific variation of the standard CRP test. CRP or C-reactive protein is synthesized by the liver and increases if there is any inflammation or acute infection in the body. The hs-CRP reports can help diagnose the risk of heart attacks(Myocardial infarction), atherosclerosis and any chronic inflammatory disease.

Coronary arteries are the most important arteries of the heart. They wrap around the heart and supply blood to the heart muscles. Similar to any other organ of our body, our heart needs oxygen-rich blood to function fully. Increased LDL levels (bad cholesterol) in the blood can cause deposition and obstruction in the natural flow of blood to the heart. It can cause the heart to lose its efficacy and may result in a heart attack(Myocardial Infarction) and probably death. This build-up of plaque is known as atherosclerosis and it adversely impacts heart health.

The high-sensitivity C-reactive protein test detects minor elevations in the normal range of CRP. In simpler terms, the higher the hs-CRP, the higher the risk of cardiovascular diseases. Moreover, hs-CRP is used in the diagnosis of heart attacks to know whether a person is at risk of experiencing it again. Depending upon your metabolic panel of cholesterol, history of heart attacks or family history of the same, the doctor will prescribe a hs-CRP test.

Globally, 17.7 million deaths have occurred due to cardiovascular disorders (CVD) and stroke. Among these, India stands at 1/5th of deaths in young individuals. Tamil Nadu, Punjab and Kerala have shown increased blood pressure levels and bad cholesterol (c-LDL), accounting for the highest deaths due to CVD. Modifiable risk factors such as smoking, obesity, hypertension, low fruit intake, stress and sedentary lifestyle are the primary causes of coronary artery disease (CAD) among Indians. However, increased diabetes mellitus and dyslipidemia are also responsible for increased cardiac morbidity (sickness) and mortality (death) rates.

Other names for the Hs-CRP test

• High-sensitivity C-reactive protein test
• HsCRP Test
• CRP for heart disease
• Cardiac CRP

What does the Hs-CRP test detect/measure and who is this prescribed for?

The hs-CRP test can help assess the following:

• Cardiac inflammation
• Blockage in coronary arteries, leading to atherosclerosis
• Chronic inflammation in the body
• The autoimmune activity of cells resulting in rheumatoid arthritis

Conditions under which your doctor will prescribe a hs-CRP test:

1. Hypercholesterolemia

High cholesterol levels in the blood tend to limit the blood flow towards the heart. Heart attack and stroke are two common symptoms of high cholesterol levels.

2. Visible signs and symptoms of a heart disease

Signs and symptoms of heart disease depend upon the type of disease. For instance, common signs of coronary artery disease, a variety of CVD are:

• Sharp chest pain in men and chest discomfort in women
• Tightness in the chest, pain and numbness
• Pain and stiffness of neck, jaw and back

3. Genetic predisposition

A family history of heart disease is likely to be inherited, i.e. passed on from parents to children.

Hs-CRP Test Range

What is the difference between hs-CRP and CRP?

What infections cause high hs-CRP?

Hs-CRP reports above 2.0 mg/L primarily indicate coronary artery disease, heart attack or a recurrent heart attack. Other conditions that might cause increased hs-CRP levels can also cause increased CRP levels. They are:

• Cardiovascular diseases
• Chronic infection [bronchitis, gingivitis, chronic obstructive pulmonary disorder (COPD)]
• Systemic Lupus erythematosus, rheumatoid arthritis
• Diabetes mellitus

Interpretation of hs-CRP test remains the same as in Table I: Hs-CRP Test Range.

The hs-CRP test detects even the slightest change in normal CRP levels that are detrimental to heart health. Table I depicts hs-CRP risk categorisation in the adult population.

Hs-CRP levels are usually measured with due consideration of the lipid panel. There are two types of cholesterol, low-density lipoprotein (c-LDL) and high-density lipoprotein (c-HDL). An increased level of c-LDL (>160 mg/dL) is a deadly risk factor for recurrent heart disorders.

The hs-CRP test results are based on testing a blood sample collected from the arm's vein.

Hs-CRP test preparation

1. Before the test

No specific preparations are needed before the hs-CRP test. However, there are a few pointers you need to take care of:

• Overnight fasting is required if your doctor has prescribed a lipid profile test along with a hs-CRP test.
• Avoid strenuous exercises and cigarette smoking before the test.
• Inform your doctor about any prior surgery, trauma or infection.

2. During the test

A nurse or phlebotomist will collect the blood sample from the vein of your arm.

3. After the test

When done hygienically(septic precautions ) and according to protocol, the hs-CRP test procedure poses no serious threats to an individual.

Test inclusions: What parameters are included?

The hs-CRP test is an advanced and sensitive quantification of the standard CRP test. Hs-CRP test results check whether any cardiac-related inflammation is present or not.

The test accounts for:

• The effect of hypercholesterolemia
• Dyslipidemia
• Breathlessness on slight exertion
• History of a heart attack

Moreover, healthy individuals with an elevated hs-CRP report are four times more likely to have coronary artery disease. Hs-CRP combined with a complete lipid profile can help estimate the risk of a heart attack.

How frequently should you take this test?

The hs-CRP test is prescribed if you have had critical levels of low-density cholesterol (c-LDL), a history of heart attack or you are at risk of developing coronary artery disease. Nevertheless, one can opt for a checkup to prevent the threat of a fatal outcome.

1. Normal hs-CRP levels mean that your heart is healthy. 50 years old and above men and 60 years old and above women can opt for a hs-CRP test once a year.
2. If hs-CRP levels are above 2.0 mg/L, repeat the hs-CRP test twice with an interval of two weeks.
3. If you have high hs-CRP levels, retest a month later.
4. People with an inactive lifestyle, increased smoking habits, obesity, diabetes mellitus and increased exhaustion after work should also opt for the test once a year.

Cardiovascular disorder (CVD), Stroke, Coronary artery disease (CAD), Peripheral artery disease (PAD)

A Hs-CRP test may have different costs depending on the city and the laboratory. Generally, the price for a Hs-CRP test falls within the range of INR 339 to INR 879. Here's a breakdown of the average expenses for a Hs-CRP test in select major cities in India: