Cholesterol is often elevated in the elderly. It is this that most often causes coronary heart disease, as well as myocardial infarction. However, there are cases when the concentration of lipids exceeds the norm in very young people, and sometimes even in children. It is possible that this is due to familial hypercholesterolemia. This severe hereditary pathology often leads to severe heart pathologies. Such a disease requires immediate treatment and the constant use of special drugs.
Inheritance
Familial hypercholesterolemia is inherited as an autosomal dominant trait. This means that the disease is transmitted to the child from the father or mother in 50% of cases. If the sick parent has only one abnormal gene, then the first signs of the disease are not immediately detected in the child, but only in adulthood (about 30-40 years). In this case, doctors say that a person inherited family heterozygous hypercholesterolemia from their parents.
A parent can also be the carrier of two copies of the defective gene. This type of inheritance is called homozygous. In this case, the disease is much more difficult. If a child suffers from familial homozygous hypercholesterolemia, then signs of atherosclerosis occur in childhood. In adolescence, severe diseases of the heart and blood vessels can be diagnosed. This can be prevented only with the help of drug therapy and constant monitoring of blood cholesterol.
A homozygous form of pathology is observed if both parents were sick in the child. In this case, 25% of the children inherit two mutated genes at once.
Since familial hypercholesterolemia is inherited autosomally dominantly, the disease occurs with equal frequency in boys and girls. However, in women, the first signs of pathology occur about 10 years later than in men.
As already mentioned, familial hypercholesterolemia is inherited only in half the cases. That is, approximately 50% of newborns are born healthy even in sick parents. Can they pass the disease on to their children in the future? According to the laws of genetics, this is impossible, because these people did not receive the defective gene. This disease cannot be transmitted through a generation.
Prevalence
Familial hypercholesterolemia is one of the most common genetic diseases. About 1 newborn out of 500 is born with this pathology. When doctors detect a persistent increase in cholesterol in a patient, then in about 5% of cases this deviation is hereditary. Therefore, an important role in the diagnosis is the collection of anamnesis. It is necessary to find out whether the parents of the patient suffered from early atherosclerosis, as well as diseases of the heart and blood vessels.
Pathogenesis
The LDLR gene is responsible for the processing of cholesterol in the body. Normally, lipids entering the body bind to special receptors and penetrate into the tissues. Therefore, their level in blood plasma is low.
If a person has a mutation of the LDLR gene, then the function of the receptors worsens, and their number decreases. Especially strong deviations from the norm are noted with a homozygous form of pathology. In this case, the receptors may be completely absent.
As a result of impaired receptor function, lipids are not absorbed by the cells and end up in the blood. This leads to the formation of plaques in the vessels. The blood flow is disturbed, as well as the nutrition of the brain and heart muscle. In advanced cases, ischemia occurs, and then a stroke or heart attack.
Provocative factors
The main cause of familial hereditary hypercholesterolemia is the LDLR gene mutation. However, there are additional unfavorable factors that can provoke an early onset of the disease or lead to aggravation of symptoms. These include:
- Abuse of fatty foods. The intake of a large amount of lipids with food with weak receptors significantly worsens the patient's condition.
- Obesity. Fat people often have high blood cholesterol .
- Taking medication. Glucocorticoid hormones, blood pressure medications, immunomodulators, and immunosuppressants can increase cholesterol.
A person suffering from familial hypercholesterolemia needs to monitor his weight and nutrition. Caution must also be exercised when taking medication.
Symptomatology
For a long time, pathology can be asymptomatic. A person most often learns about a disease only by the results of a blood test for biochemistry. With familial hypercholesterolemia, the lipid level in the analysis is sharply increased.
A characteristic symptom of the disease is the appearance of cholesterol deposits (xanthomas) on the tendons. They look like bumps on the elbows, knees, buttocks and fingers. This leads to inflammation of the joints and tendons. Such manifestations of pathology with a heterozygous form of the disease occur at the age of 30-35 years.
With hypercholesterolemia of a homozygous type, xanthomas can be detected already in childhood. Deposits of cholesterol are found not only in the tendons, but also on the cornea of the eye.
Patients often have a gray line around the iris. It has the shape of a half ring. Doctors call this sign of hypercholesterolemia a "senile arch."
At an early age, a person may experience pain in the heart. This is a sign of ischemia. Due to blockage of blood vessels by cholesterol plaques, myocardial nutrition worsens.
Attacks of headache and dizziness may also occur. Patients often have persistent arterial hypertension. Due to pathological changes in the vessels, cerebral circulation is disturbed.
Complications
Familial hypercholesterolemia is a serious illness that, if untreated, can be fatal. The most dangerous consequences of pathology are myocardial infarction and stroke. Damage to the heart and blood vessels is often noted at a young age. The risk of developing such pathologies depends on the form of the disease, as well as on the age and gender of the person.
With a heterozygous form of the disease, the following consequences are observed in patients:
- In half of men and 12% of women, ischemia of the heart and brain occurs before the age of 50 years.
- By the age of 70, 100% of men and 75% of women with this disease have vascular and heart pathologies.
With a homozygous form of pathology, coronary artery disease is noted in childhood. This type of hypercholesterolemia is difficult to treat. Even with timely therapy, the risk of a heart attack remains very high.
Diagnostics
The main method for diagnosing familial hypercholesterolemia is a blood test for cholesterol and low density lipids. Patients have a persistent increase in plasma fats.
An ECG with a stress test is performed. In patients, an adverse reaction of the heart muscle to the load and signs of ischemia is determined. Research helps determine the risk of heart attack.
To identify the hereditary nature of the disease, a genetic blood test is done. This allows you to accurately determine the etiology of hypercholesterolemia. However, such a test is carried out only in specialized laboratories. This is an expensive study, in addition, the analysis is done for quite some time. Therefore, the treatment of pathology is most often started, without waiting for the results of a genetic test.
Treatment of heterozygous form
With the heterozygous form of the disease, the patient is recommended to review his lifestyle and diet. Prescribe a diet with a restriction of fat intake, but with a high fiber content. It is forbidden to eat spicy, smoked and fatty dishes. It is recommended to eat more vegetables and fruits. It is important for patients to remember that without dieting, drug treatment will not have any effect.
Also, patients are recommended to include the following products in the diet:
- rice
- vegetable oil;
- nuts
- corn.
These foods contain substances that lower cholesterol.
Patients are shown moderate physical activity and an active lifestyle. It is necessary to completely stop smoking and drinking alcohol.
However, these measures are not enough to permanently lower cholesterol. Therefore, patients are advised to take statins. These drugs help to normalize blood lipids. In many cases, lifelong administration of the following drugs is indicated:
- "Simvastatin."
- "Lovastatin."
- Atorvastatin.
In addition, medications are prescribed that reduce the formation of cholesterol in the liver, for example, “Holistiramine” or “Clofibrate”, as well as “Nicotinic acid”.
Treatment of a homozygous form
This form of the disease is most difficult and can be treated with great difficulty. With homozygous hypercholesterolemia, the patient has to enter high doses of statins. But even such therapy does not always give an effect.
In such cases, the patient is given plasmapheresis. Blood is passed through a special apparatus and it is cleaned of lipids. This procedure has to be carried out constantly.
In very severe cases, liver transplantation is indicated. An ileum surgery is also performed. As a result of such surgical intervention, cholesterol gets into the bloodstream.
Forecast
The prognosis for a heterozygous form of the disease is more favorable than for a homozygous one. However, without treatment, 100% of men and 75% of women die from myocardial infarction or stroke at the age of about 70 years.
The homozygous form of hypercholesterolemia has a very serious prognosis. In the absence of therapy, patients can die by the age of 30. But even with treatment, a very high risk of heart attack remains.
In recent years, medical scientists have been conducting research in the treatment of this dangerous disease. Protein preparations for treatment are being developed. Gene therapy methods are also being studied.
Prevention
Currently, specific prevention of this disease has not been developed. Modern medicine cannot affect mutated genes. This disease can be detected in an unborn child only with the help of prenatal diagnostic methods.
Every couple planning a pregnancy should be examined and consulted by a geneticist. This is especially necessary in cases where one of the future parents suffers from hypercholesterolemia of an unknown etiology.
If a person has high cholesterol at a young age, then you need to pass a genetic test for hereditary hypercholesterolemia. If the diagnosis is confirmed, it is necessary to take statins for life and follow a diet. This will help prevent an early heart attack or stroke.