For some time now, homocysteine has been linked to heart problems. But what does it mean? When is it necessary to have a homocysteine test? What are the indications for high and low homocysteine? In this article we will answer all these questions.

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What is homocysteine?

First, we need to explain what homocysteine is. To help us, we talked to Dr. Nilton Carneiro, cardiologist at Santa Catarina Hospital.

According to the expert, homocysteine is a type of amino acid. Called an intermediate, its particles form the proteins Homocysteine is an intermediate amino acid, formed for the conversion of methionine into cysteine," he adds.

Therefore, this amino acid is formed in the body due to the ingestion of proteins. Furthermore, when it is present in the blood plasma, it is related to the onset of cardiovascular diseases.

What is homocystinuria?

The cardiologist comments that there is a pathological condition called homocystinuria: "It is a genetic disease, that is, an autosomal recessive disease, characterized by elevated homocysteine in the blood and urine.

Homocystinuria is the excess of homocysteine, i.e., it is a disease caused by an enzyme deficiency that prevents the correct metabolism of amino acid which then accumulates in the body.

Therefore, homocystinuria is a problem in homocysteine metabolism, an autosomal recessive disease in which the enzyme cystathionine-β-synthetase (CβS) is deficient.

Diagnosis of homocystinuria

According to the doctor, "the diagnosis is often made early in childhood, with neurological changes, some cognitive deficit, typical changes of osteoporosis It's not just a question of the age of the child, but also of the age of the child's brain, eye changes, and increased chances of thrombosis, vascular disease, and premature atherosclerosis," she says.

Therefore, the diagnosis is made by combining these clinical signs with an analysis of the levels of the amino acids homocysteine and methionine in the blood plasma, as shown in the test.

When is the homocysteine test indicated?

This type of examination is requested by the doctor when it is necessary to investigate the risk of cardiovascular diseases This is because with the results presented it is possible to verify the high amount of this amino acid in the bloodstream, indicating a higher risk of cardiovascular diseases.

These diseases can be stroke, coronary heart disease, thrombosis, or heart attack, as their elevated levels can cause changes in the blood vessels. Besides being indicated for checking the risk of heart disease, the test can also monitor problems related to the thyroid and kidney diseases.

A trained physician will analyze the changes in circulating levels of this amino acid, and will order other blood tests to help make the diagnosis.

What are the normal reference values?

There are some reference values that can indicate a patient's risk of cardiovascular disease; however, these values may vary by laboratory.

Generally, the level is considered normal when the test indicates a value between 5 and 15 µmol/L. Understand the reference values that can indicate some risk of cardiovascular disease:

• Low risk of cardiovascular disease: between 15 and 30 µmol/L;
• Intermediate risk of cardiovascular disease: between 30 and 100 µmol/L;
• High risk of cardiovascular disease: greater than 100 µmol/L.

What does high homocysteine mean?

According to studies of the project Determination of Plasma Homocysteine Levels in the Population of São Paulo, high levels of homocysteine increase by at least 42% the risk of unstable angina A heart problem that can recur over and over again.

However, according to Dr. Nilton Carneiro, some elevation is common in the population: "around 5% may have this increase, but rarely should it accomplish anything," he reassures.

However, if you have these clinical manifestations together, then the specialist informs that it is worthwhile to perform the test. After all, the doctor states that there are other situations that can increase homocysteine as well, such as malignant diseases, oncological diseases, kidney dysfunction, and some medications.

Consequences of high dosage

To understand the consequences of high homocysteine concentration in organism We need to explain that blood clots form due to high levels of this amino acid.

In turn, the high concentration of homocysteine further suppresses arterial passages, consequently decreasing blood flow. The lack of blood flow to the brain is one of the main causes of stroke, with the formation of blood clots in the brain.

What does low homocysteine mean?

The low homocysteine that shows up in the test can have different motivations, such as vitamin B supplementation or folic acid especially during pregnancy, since these substances decrease the concentration of homocysteine in the blood.

However, normally, values slightly below the reference value are not worrisome.

However, when the cause of the homocysteine decrease indicates vitamin B or folic acid supplementation, for example, the medical specialist may recommend discontinuing or changing the dosage of these supplements until the concentration returns to the normal reference value.

When and how is treatment for elevated homocysteine done?

Finally, the cardiologist informs that it is possible to seek treatment with a specialist in metabolic diseases and by a nutrologist.

"Although this high homocysteine rate is associated with cardiovascular and thrombotic diseases, studies can't show that by reducing homocysteine by giving some vitamins or folate, for example, nutrients important for our metabolism, will be able to decrease the cardiovascular event rate", he reminds us.

Therefore, Dr. Nilton Carneiro informs that there is a way to treat and eventually reduce some damage, except heart attacks and cardiovascular events.

Furthermore, for each case of altered homocysteine levels in the blood, the physician in charge will be able to indicate the best form of treatment.

After all, levels below the reference value can result in the failure of the immune system and the fight against oxidative stress, and can lead to cell death and toxic effects in the body.

Source: Dr. Nilton Carneiro, cardiologist at Santa Catarina Hospital - Paulista.