Genetic predisposition? Environmental influence? Or disease? Uncovering the multiple causes of hyperlipidemia

Author: Liu Wenxian, Chief Physician, Beijing Anzhen Hospital, Capital Medical University

Reviewer: Zhang Haicheng, Chief Physician, Peking University People's Hospital

Hyperlipidemia, also known as high blood lipids, is a condition in which the fat content in the blood is abnormally high, mainly involving abnormal levels of triglycerides and cholesterol. This disease does not have a single cause, but is the result of a combination of genetic, environmental and secondary factors.

1. Genetic factors: warning signs of familial hypercholesterolemia

Genetic factors play a key role in the development of hyperlipidemia. Familial hypercholesterolemia is a hereditary disease in which patients have specific gene mutations that cause dysfunction of the low-density lipoprotein (LDL) receptors on the cell membrane, making it impossible to effectively remove LDL cholesterol from the blood, ultimately causing abnormally high cholesterol levels in the blood. This disease may manifest in childhood, manifesting as hypercholesterolemia, which significantly increases the risk of early-onset cardiovascular disease.

Familial hypercholesterolemia usually follows an autosomal dominant inheritance pattern, meaning that only one mutated gene is required to develop the disease. Patients with homozygous variants (mutations in both genes) have more severe disease, higher lipid levels, and an earlier age of onset. Therefore, early identification and screening are critical for families with a history of familial hypercholesterolemia, especially if family members have developed cardiovascular disease at a younger age. Regular lipid testing can detect potential problems in a timely manner, which is especially important for children and adolescents, so that early intervention can be made to avoid complications.

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2. Environmental factors: the chain reaction of bad living habits

Environmental factors also play an important role in the development of hyperlipidemia. The rapid changes in modern lifestyles have made it easier for people to fall into bad habits, such as lack of exercise, overeating, obesity and mental stress. These factors may affect the body's normal metabolic mechanism and cause abnormal increases in blood lipid levels.

First of all, lack of exercise is one of the important factors leading to hyperlipidemia. Appropriate exercise can promote body metabolism, accelerate the burning and metabolism of fat, and thus reduce blood lipid levels. However, with the accelerated pace of modern life, it is increasingly difficult for people to find time for exercise. Long-term lack of exercise can lead to decreased body function and excessive fat accumulation, which in turn causes hyperlipidemia.

Secondly, overeating and obesity are also important causes of hyperlipidemia. Excessive intake of high-calorie foods will lead to excess energy in the body, which is converted into fat and stored in the body. Obesity will increase the metabolic burden on the body and cause abnormal fat metabolism, which will lead to increased blood lipid levels. In addition, some unhealthy eating habits, such as high-fat, high-sugar, and high-salt diets, may also lead to abnormal blood lipid levels.

Mental stress is also one of the potential causes of hyperlipidemia. Long-term mental stress can lead to endocrine disorders in the body, affecting fat metabolism and blood lipid levels. Therefore, maintaining a good attitude and reducing mental stress are equally important for preventing hyperlipidemia.

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3. Secondary factors: the influence of systemic diseases

In addition to genetic and environmental factors, some systemic diseases may also indirectly lead to abnormal lipid metabolism, including diabetes, hypothyroidism, and liver disease.

Diabetes is a common metabolic disease. Patients often have problems such as insulin resistance and insufficient insulin secretion. These problems cause the body to be unable to use glucose as an energy source and instead rely on fat decomposition to generate energy. This will lead to an increase in free fatty acids in the blood, which in turn promotes the liver to synthesize more cholesterol and triglycerides, leading to increased blood lipid levels.

Hypothyroidism is also a common endocrine disease. Thyroid hormone is one of the important hormones to maintain normal metabolism of the body. When thyroid hormone secretion is insufficient, the body's metabolic rate will decrease and fat metabolism will also be affected. This will lead to increased blood lipid levels and increase the risk of cardiovascular disease.

Liver disease may also lead to abnormal blood lipid metabolism. The liver is one of the important organs for fat metabolism and is responsible for the synthesis, decomposition and excretion of fat. When the liver is damaged or affected by disease, its fat metabolism function will be affected, leading to abnormally high blood lipid levels. For example, liver diseases such as hepatitis and cirrhosis may lead to high blood lipid levels.

For these patients with systemic diseases, treating the underlying disease is one of the important measures to control blood lipid levels. By controlling blood sugar, improving thyroid function or treating liver disease, blood lipid levels can be effectively lowered and the risk of cardiovascular disease can be reduced.