Cholesterol: its benefits and drawbacks

2022. May 25.

Cholesterol, a very important building block in all cells of our body, is involved in the synthesis of certain hormones, bile acids and vitamin D. Chief physician Dr. Bernadett Voloncs, cardiologist and internist at Dr. Rose Private Hospital, spoke on the subject.

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"There are several types of cholesterol, as we can see in our laboratory results. The laboratory test determines total cholesterol levels, including two fractions: LDL and HDL cholesterol.

"LDL is also known as bad cholesterol, the reason being that it is the fraction of total cholesterol that can deposit on the walls of blood vessels to form plaques, thus narrowing the blood vessels. HDL cholesterol is the so-called good cholesterol, the fraction that has a cleansing function, i.e., it transports cholesterol from the blood vessel wall to the liver for excretion and breakdown," explains Dr. Bernadett Voloncs. "It follows that the higher the HDL cholesterol level, the more protective it is against atherosclerosis."

High cholesterol has no symptoms. It can be diagnosed by routine laboratory tests, but unfortunately in most cases it is only in the context of a complication, a heart attack or stroke, that high cholesterol is discovered. The causes are partly lifestyle related: poor diet, smoking, a sedentary lifestyle.

Less commonly, high cholesterol may also have a genetic cause. A genetic defect can lead to a significant increase in cholesterol levels at a young age and early complications. Statistically, it affects one in 250 people. That is why it is always very important for the doctor to know the family background and the medical history. And from the patient's point of view, if there is a family history of stroke or heart attack, cholesterol monitoring is recommended at a young age.

The target level, i.e., the cholesterol level above which the doctor should start to prescribe medication, depends on many factors: age, co-morbidities, and previous history of heart attack or stroke.

"I always say to patients that we should not treat the cholesterol level seen in the laboratory result - the target value shown is for patients at low cardiovascular risk - but that we should aim to achieve a target value appropriate to the patient's cardiovascular risk status. The targets for a low-, medium-, high- and very high-risk patient are quite different. These may change every few years based on European and American recommendations," says Dr. Voloncs.

"Today, the goal after a heart attack or stroke is a low cholesterol level, which cannot be achieved by lifestyle changes alone. In such cases, but also in primary prevention, medication has an important role to play alongside lifestyle changes.

High cholesterol levels, including high LDL cholesterol levels, together with elevated triglyceride levels - known as blood lipids - can trigger lipid deposition on the blood vessel wall, leading to plaque formation. Over time, this can limit blood flow in a section of blood vessel, contributing to poor blood supply to that organ. In acute cases, it can also cause complete blockage of the vessel, leading to myocardial infarction if it affects the heart or stroke if it affects the brain. Therefore, it is very important to know your cholesterol level, as LDL cholesterol is one of the most important risk factors for cardiovascular mortality, which is the leading cause of death, along with cancer, in Hungary today.

One of the most important factors in reducing or maintaining LDL cholesterol to normal levels is lifestyle change. Physical activity is part of the treatment, with a minimum weekly recommendation of 150 minutes of moderate-intensity cardio exercise, which can be achieved with just a brisk walk. Smoking and the use of all forms of tobacco products should be avoided. It is also important to manage blood pressure and, if it has developed, diabetes.

"Lifestyle changes may no longer be enough. In such cases, the doctor may decide that medication is needed to bring LDL cholesterol levels down to target levels, thereby significantly reducing the risk of cardiovascular mortality. The first step in treatment today is statin therapy. A drug containing this active substance inhibits the formation of cholesterol in the liver. These drugs are very effective, they can reduce baseline LDL cholesterol levels by up to 50 percent," explains Dr. Voloncs.

In very high-risk patients, the target is much lower, and a combination of treatment may be needed: in addition to statins, drugs that inhibit the absorption of dietary cholesterol are used. These can be given with support only if medically indicated for secondary prevention, i.e., after a stroke or heart attack. In patients at high cardiovascular risk, or even in those with genetically significantly elevated cholesterol levels, if the target is not reached with combination therapy, treatment by injection is also an option. This therapy is also available in Hungary and should be administered by subcutaneous injection every six months. It can reduce cholesterol levels by an extra 50 percent compared to combined drug therapy. Achieving a patient-specific target level of LDL cholesterol in the long term can reduce the risk of developing cardiovascular disease, its complications and associated mortality.