Overview: What is hypercholesterolemia?
Cholesterol is an important building block in the body. It belongs to the lipids (fats) and is needed to build cell membranes. 95 percent of human cholesterol is found in the cells. Cholesterol is also used to produce vitamin D, bile acid and sex hormones. In hypercholesterolemia (hyper = over), there is too much cholesterol in the blood. This affects older people in particular, as the total cholesterol level rises significantly with age.
Most cholesterol is produced by the body itself. We only absorb a small proportion through food. If there is too much cholesterol in the blood, there is an increased risk of arteriosclerosis (hardening of the arteries). The risk of cardiovascular disease increases, especially in combination with little exercise, tobacco consumption and severe obesity. This is why high cholesterol levels are considered harmful. However, how the values should be interpreted in detail has been the subject of debate for years. In 2019, the European Society of Cardiology (ESC) and the European Atherosclerosis Society (EAS) lowered many threshold values based on new study data. Although other factors are also important, the reduction of LDL cholesterol (low density lipoprotein) is central to the prevention of atherothrombosis.
Familial hypercholesterolemia
In familial hypercholesterolemia – a genetic and inherited disease – LDL is particularly high (>5 mmol/L). Familial hypercholesterolemia already occurs in childhood. This means that the risk of premature deposits in the blood vessels is relatively high. In most cases, several members of the family are affected by hypercholesterolemia and strokes or heart attacks at an early age. The clinical diagnosis of familial hypercholesterolemia can be made by calculating the DLNC score (www.agla.ch). However, high LDL cholesterol can be caused not only by hereditary diseases but also by certain other diseases:
In this case we are talking about secondary hypercholesterolemia.
Hypercholesterolemia: frequency and age
Hypercholesterolemia occurs in very many people – around a third of the population in Central Europe has an elevated cholesterol level. As cholesterol levels rise with increasing age, older people are particularly affected. However, hypercholesterolemia is not a disease in itself, but only the consequences of it: the excess cholesterol is deposited in the arteries, plaques (deposits) form and the arteries become increasingly narrow. This increases the risk of stroke and heart attack or peripheral arterial occlusive disease with a high risk of deterioration in quality of life or increased mortality. Overall, however, people in Switzerland have a lower risk of cardiovascular disease than other countries in Northern or Eastern Europe.
Around two to four out of 1000 people in Switzerland suffer from familial hypercholesterolemia. They often develop arteriosclerosis at an early age. However, many cases of familial hypercholesterolemia are not detected.
Clinical picture: causes and risk factors
However, high LDL cholesterol levels usually only become dangerous in combination with other risk factors:
Food plays an important role. More recent findings no longer aim to ban eggs and butter from the diet as in the past; a balanced diet with plenty of fruit and vegetables is more important. Meat should only play a minor role, with whole grain products, pulses and healthy oils taking center stage alongside fruit and vegetables.
Hardly any symptoms: Hypercholesterolemia is not noticeable
Elevated cholesterol levels do not cause any symptoms. This is why they are usually only noticed when it is too late – for example, when arteriosclerosis has already set in. You can only find out if your cholesterol levels are too high with the help of a blood test. If cholesterol levels are very high, deposited cholesterol may be visible as slightly raised xanthelasma on the eyelids or other skin changes. However, this symptom, as well as the white opacity of the cornea caused by hypercholesterolemia, also occurs in other diseases.
Hypercholesterolemia: Diagnosis with us
If you suspect that your cholesterol levels may be too high, we will measure your cholesterol levels. We will recommend this blood test in particular for risk factors such as smoking, high blood pressure or obesity. You must be fasting when the blood sample is taken, i.e. you must not have eaten for at least twelve hours. In addition to total cholesterol, we also check the values for HDL and LDL cholesterol. As blood lipids (triglycerides) are also elevated in some lipid metabolism disorders, we often order this value as well. If familial hypercholesterolemia or early atherothrombotic diseases are suspected, the determination of lipoprotein(a) is also recommended.
The exact point at which cholesterol levels become dangerous cannot be determined for everyone. For this reason, the European Cardiology Society has created tables that relate the risk of cardiovascular disease to total cholesterol levels. In Switzerland, a risk calculator has been adapted to the Swiss population and can be found on the AGLA website. If there are known cases of premature cardiovascular disease in the family, and the higher the blood pressure, age and total cholesterol level, the greater the risk. Smokers have a higher risk than non-smokers, and men have a higher risk than women. At the same time, a high HDL value lowers the risk, while a high LDL value increases it.
What your cholesterol levels say
We can only determine your individual risk of cardiovascular problems on the basis of your lifestyle and other physical data. However, some guidelines apply:
- Safe: If your total cholesterol is below 5 mmol/L and your triglycerides are below 2 mmol/L and your HDL cholesterol is above 1 mmol/L, you have nothing to worry about.
- Moderate hypercholesterolemia: If your total cholesterol is between 5 and 7.5 mmol/L, your LDL cholesterol <3 mmol/L and your triglycerides 2 mmol/L, you should change your lifestyle.
- Severe hypercholesterolemia: your total cholesterol level is above 5 mmol/L, your blood pressure is above 150 mmHg and your LDL cholesterol level is above 4 mmol/L, while at the same time triglycerides are below 2 mmol/L.
High blood pressure increases the risk, as does smoking or suffering from kidney disease. We will therefore also measure your blood pressure and pulse and listen to your heart and lungs. In some cases, we will also order the blood glucose value and the HbA1c value. If familial hypercholesterolemia is suspected, a genetic test may be necessary.
Hypercholesterolemia: prevention, early detection, prognosis
You can do a lot yourself to prevent hypercholesterolemia. It is important to get plenty of exercise in everyday life – we recommend at least half an hour of sweat-inducing sport several times a week. Even with a healthy diet, you can reduce LDL cholesterol on the one hand and strengthen HDL cholesterol on the other. You should avoid fatty meat, convenience foods, products made from white flour (pizza, pastries, pasta), fried foods and fatty foods. You should eat a lot of the following foods in particular:
- Vegetables (carrots, peppers, cucumber, lettuce, mushrooms…)
- Fruit (apples, berries, cherries, oranges…)
- Wholemeal products (bread, wholemeal pasta, unhulled rice…)
- Pulses (lentils, chickpeas, beans, peas)
- Water/mineral water
- Nuts (up to a handful a day)
- Low-fat dairy products
- lean fish
- Olive oil, rapeseed oil
Course and prognosis of hypercholesterolemia
Experts in Switzerland recommend that cholesterol levels should be measured every five years in men aged between 35 and 65 and in women aged between 45 and 65. If hypercholesterolemia is detected in time, you can prevent harmful effects by changing your behavior and – if necessary – by taking medication. The earlier a high cholesterol level is detected, the lower the risks. If you adapt your diet and lifestyle early on, you can stay healthy into old age. However, in the case of familial hypercholesterolemia, life expectancy is reduced due to the high risk of cardiovascular disease.
Clinical picture: Treatment for hypercholesterolemia
The aim of any therapy for hypercholesterolemia is to lower the LDL level. Regardless of the use of pharmacological therapy, a healthy lifestyle is recommended. It is definitely worth eating healthier, exercising more and giving up tobacco and nicotine. If pre-existing conditions or medication are the triggers, we will treat these or switch to alternative active ingredients. This is followed by regular checks of your cholesterol levels.
However, if there is no improvement in cholesterol levels despite these measures, or if the vessels are already severely affected by arteriosclerosis, we prescribe medication. The first are the statins. These suppress the production of cholesterol in the liver. As a result, the liver cells absorb more LDL cholesterol in order to maintain their value. As they do not produce any new cholesterol at the same time, the cholesterol level in the blood drops – by about half in most people. However, not all patients respond equally well to this active ingredient.
Familial hypercholesterolemia is treated in the same way as acquired hypercholesterolemia. In some cases, however, statins do not help at all with inherited hypercholesterolemia. If, for example, the LDL receptors on the surface of the liver are missing for genetic reasons, no LDL cholesterol can enter the liver cells. If statins do not work or are not tolerated, we use ezetimibe (cholesterol absorption inhibitor) or PCSK9 inhibitors. Replacement resins are used less frequently. We often use these medications in combination.