Already have high cholesterol at a young age? Family inheritance: increased risk of cardiovascular disease

Many people smell bad cholesterol and quit the bad habit of eating fried and fatty foods to avoid life-threatening strokes and heart attacks caused by excessive cholesterol.¹ However, some people are born with the problem of high cholesterol. Even if they try to adjust their diet and maintain regular exercise, their cholesterol remains high.² Dr. Li Chun Hong, a specialist in endocrinology and diabetes, reminded that familial hypercholesterolemia (Familial hypercholesterolemia) is a congenital genetic disease. Because the patient’s risk of cardiovascular disease is greatly increased, low-density cholesterol (commonly known as low-density cholesterol) must be reduced through drugs. Only by reducing bad cholesterol (bad cholesterol) to ideal levels can we effectively reduce the risk of cardiovascular disease.²

Related to genetic mutations

Familial hypercholesterolemia is one of the most common genetic diseases in the world caused by a single gene mutation^3,4 Dr. Li explained that most patients have mutations in the low-density lipoprotein receptor gene, which prevents the liver from properly clearing bad cholesterol. As a result, the bad cholesterol in the patient’s blood has been at a high level since birth, so Atherosclerosis and blood vessel blockage will develop earlier than the average person, greatly increasing the long-term risk of cardiovascular problems such as coronary heart disease, stroke and peripheral arterial disease.^2-4 This disease is divided into two types depending on the way of genetic inheritance: “The first type is to inherit the disease-causing gene from one parent. The disease is relatively mild. About one in every 200 to 250 people in the world suffers from it, which is a high rate. The other is that the disease is inherited from one parent. One type inherits the disease-causing gene from both parents at the same time, and the condition is obviously more serious. There is only one patient in every 160,000 to 320,000 people, which is quite rare.”^3,4

Patients have a higher risk of cardiovascular disease than the general population

Dr. Li emphasized that patients with familial hypercholesterolemia have had high cholesterol problems since birth, so their risk of cardiovascular disease is more than 10 times higher than that of the general population, and the disease tends to occur at a younger age. ^2,4。”People in their 20s and 30s are young and should be healthy and free from disease and pain. However, as the concentration of bad cholesterol in the blood continues to be high, their blood vessels have actually been damaged over time, causing premature aging and blockage of blood vessels, leading to premature coronary heart disease. , stroke, etc., the consequences are quite serious”^3,5 Therefore, patients should receive early diagnosis and treatment to reduce the risk of cardiovascular disease. The clinical symptoms of patients mainly include xanthomas on the hands and heels, or xanthomas on the skin near the eyes, but some patients may not have any symptoms.³ Dr. Li suggested that even if they do not have the above symptoms, high-risk individuals (such as close relatives with a family history of hypercholesterolemia or premature cardiovascular disease, as well as patients with premature cardiovascular disease) should take the initiative to have their cholesterol tested. “If the cholesterol level is obviously normal, there is basically a small chance of inheriting the disease. If high cholesterol and related clinical features are found at the same time, familial hypercholesterolemia can basically be diagnosed. If necessary, the diagnosis can be confirmed through genetic testing result.⁶ Confirmed patients should also take the initiative to notify their close relatives to receive examinations as soon as possible to avoid delaying their condition.”

Drugs are the key to treatment

Once familial hypercholesterolemia is diagnosed, the patient must take medications and adopt healthy lifestyle habits to lower cholesterol. Dr. Li said: “About 70% to 80% of cholesterol in the human body is produced by the liver, and only 20% to 30% comes from the diet.⁷ Familial hypercholesterolemia is not an urban disease caused by poor diet and living habits, but a hereditary disease. Because the patient’s liver’s ability to process cholesterol is significantly reduced, even if the patient tries to quit eating, the cholesterol will still remain high. Therefore, it is necessary to control diet alone. (such as avoiding large fish, meat and trans fats) are not very helpful in improving cholesterol levels8,9. Although regular exercise is only auxiliary, it can help improve cardiopulmonary function, promote overall health and reduce weight. Maintaining a standard weight can help reduce the risk of cardiovascular disease.” ^3,10 Taking cholesterol-lowering drugs regularly is the key to treatment, and patients must be mentally prepared to take drugs for life. Commonly used types of drugs include statins, cholesterol absorption inhibitors and PCSK9 inhibitors⁴ He said that the first two are oral drugs, among which statins are the first-line cholesterol-lowering drugs. Large-scale studies have proven that they can effectively reduce bad cholesterol and the risk of cardiovascular disease. However, a small number of people will experience elevated liver enzymes and Side effects such as muscle soreness and high muscle enzymes⁴, before prescribing drugs, possible side effects will be clearly explained to the patient and monitored, and the drugs will be adjusted if necessary. Another type of oral cholesterol absorption inhibitor works by reducing intestinal absorption of food cholesterol. It is safe and common side effects include abdominal discomfort or diarrhea. If statins fail to bring bad cholesterol up to target, cholesterol absorption inhibitors can be added along with statins.^4,11 However, some patients with familial hypercholesterolemia still fail to reduce bad cholesterol to target levels by relying on the above two oral drugs. Therefore, doctors will consider adding PCSK9 inhibitors to patients to further lower cholesterol.⁴ On the other hand, if patients cannot tolerate the adverse effects of oral medications, PCSK9 inhibitors are also effective alternative treatments.⁴ PCSK9 inhibitors are subcutaneously injected drugs that can effectively increase the level of low-density lipoprotein receptors in the liver, allowing them to restore their function of clearing bad cholesterol in the blood and achieve cholesterol-lowering effects4. Clinical studies have shown that PCSK9 inhibitors have good safety profiles. Common side effects include the possibility of temporary mild redness and swelling at the injection site and flu-like symptoms.^4,12

Bad cholesterol target levels

How do patients with familial hypercholesterolemia meet the bad cholesterol level? Dr. Li pointed out that major medical organizations in Europe and the United States have increasingly strict requirements on bad cholesterol levels. “For example, in 2019, the European Society of Cardiology recommended further tightening the requirements for bad cholesterol levels: patients with familial hypercholesterolemia, if they have no other risk factors for vascular disease and are in the high-risk group, should have lower levels. above 1.8 mmol/L, and a 50% decrease; if the patient is already complicated by cardiovascular disease, or has other cardiovascular disease risk factors (such as diabetes, hypertension, chronic kidney disease, smoking, close relatives with a history of premature cardiovascular disease, etc.) , it belongs to the very high risk group, the level should be less than 1.4 mmol/L, and the 50% reduction.”⁴ He added that patients should regularly monitor their vascular conditions through non-invasive examinations to detect cardiovascular disease early⁴, then provide appropriate treatment. For example, exercise electrocardiogram can increase the load on the heart through exercise, thereby monitoring the electrocardiogram for signs of myocardial ischemia. It is one of the commonly used examination methods for diagnosing coronary heart disease.¹³ Carotid artery ultrasound can assess whether the large arteries in the neck have stenosis and the risk of stroke.¹⁴ Source：https://heart2heart.mingpao.com/年紀輕輕已有高膽固醇-家族遺傳-心血管疾病風險大增/