Genetics and High Cholesterol: Link, Risks, and More

Cholesterol plays an important role in the body, but high levels of low-density lipoprotein (LDL) cholesterol can increase the risk of cardiovascular disease. There are several causes of high LDL cholesterol. One possible cause is the genetic disorder familial hypercholesterolemia.

This article describes the link between genetics and high cholesterol. It provides an overview of familial hypercholesterolemia (FH), including its symptoms, diagnosis, treatment, and outlook. We also outline some other causes of high cholesterol and list some steps people can take to prevent high cholesterol.

High cholesterol can have a genetic cause. The medical term for this is familial hypercholesterolemia (FH).

Estimates suggest that 1 in 250 people have FH. According to the Centers for Disease Control and Prevention (CDC)If a biological parent has FH, their offspring have a 50% chance of having the condition. If both biological parents have FH, their offspring may have a more severe form of the condition, which doctors refer to as “homozygous FH.”

FH also seems to be more common in people of certain ethnicities. According to the American College of Cardiology, the prevalence of the condition in people of different ethnicities is as follows:

  • Black people: 1 in 211 people
  • white people: 1 in 249 people
  • Mexican Americans: 1 in 414 people
  • other ethnicities: 1 in 343 people

Lipoproteins are proteins that transport cholesterol throughout the body. There are two main types::

  • LDL cholesterol, or “bad cholesterol”: This type can build up in the arteries, impairing blood flow and increasing the risk of cardiovascular disease.
  • HDL cholesterol or “good cholesterol”: This type absorbs cholesterol and transports it back to the liver, which then removes it from the body. In this way, HDL helps prevent LDL from getting too high.

FH impairs the body’s ability to remove LDL cholesterol from the blood. The excess cholesterol builds up in the arteries and forms plaques that impede blood flow. In this way, FH significantly increases the risk of cardiovascular diseases, such as heart attack and stroke.

According to the CDC, 60-80% of people with FH also have a mutation in one of the following three genes:

  • LDLR gene: Provides the instructions for making LDL receptors on the outside of certain cell types. The LDL receptors pick up circulating LDLs in the blood and bring them to the cell to use.
  • APOB gene: It allows LDLs to attach to LDL receptors, particularly those on liver cells.
  • PCSK9 gene: Regulates the number of LDL receptors, making it important for controlling blood cholesterol levels.

People with FH who do not receive treatment for the condition are 20 times more likely to develop coronary artery disease (CAD). This disease impedes the flow of oxygenated blood to the heart.

According to the National Organization for Rare Disorders, men who do not receive treatment for FH have a 50% chance of having a heart attack by age 50, while women who do not receive treatment have a 30% chance of having one by age 50. the age of 60 years. In addition, these risks increase for people who smoke or have diabetes.

However, it is important to note that a person with FH will not necessarily have a heart attack.

FH is not the only cause of high cholesterol. Other major causes include obesity and type 2 diabetes.

Being obese can increase the risk of high cholesterol, special if a person carries excess fat around their waist. Medical professionals call this “central obesity,” and the condition indicates excess fat around the internal organs.

Obesity too increases a person’s risk from developing type 2 diabetes, another risk factor for high cholesterol. Diabetic dyslipidemia is a condition that doctors characterize by: increased LDL and lowered HDL.

Type 2 diabetes can occur as a result of a diet lacking in nutritious foods and a lack of exercise. However, it can also have a genetic component. The more family members who have type 2 diabetes, the more likely someone is to develop the condition.

Not everyone with FH experiences symptoms. however, the CDC notes that the following can sometimes be a sign of the condition:

  • bumps or lumps around the knees, knuckles, or elbows
  • swelling or pain in the Achilles tendons
  • turning yellow around the eyes
  • a whitish-grey crescent on the outside of the cornea, the protective layer of the eye

The above symptoms are due to the accumulation of cholesterol in the relevant parts of the body.

Doctors may consider a diagnosis of FH if the following factors are present:

  • In children:
    • LDL greater than 160 milligrams per deciliter (mg/dl)
    • a family history of FH or early heart disease
  • In adults:
    • LDL higher than 190 mg/dl
    • a personal or family history of CAD at a younger age than expected
    • physical signs or symptoms

In addition, most people with FH have a family history of early heart disease or heart attacks.

Both children and adults can experience the above symptoms of FH.

Doctors may also order genetic testing to clarify whether a person has FH. These tests check for variations in one of three genes: LDLR, APOBand PCSK9. however, the CDC states that other genes likely play a role in FH. As such, a person can be diagnosed with FH even if a genetic test for one of these three genes gives a negative result.

The CDC states that people with FH typically need medications to lower their cholesterol to healthy levels. People with FH often need a combination of medications to regulate their LDL levels. These may include cholesterol-lowering drugs called statins and PCSK9 inhibitors.

Diet and lifestyle changes for people with FH include:

  • avoiding smoking or vaping, if applicable
  • eating a diet high in fresh fruits, vegetables, and fiber
  • limiting saturated fats, trans fats, salt, and foods with added sugar
  • limit alcohol consumption
  • participate in regular exercise
  • maintain a moderate body weight
  • regularly monitor and monitor blood pressure and cholesterol levels

In addition, people with FH should be treated for any accompanying cardiometabolic conditions, such as high blood pressure or type 2 diabetes.

The CDC offers the following recommendations to keep cholesterol levels in a healthy range and prevent cardiovascular disease:

  • Making Nutritious Food Choices: This includes:
    • limiting the intake of saturated and trans fats, sugar and salt
    • choose healthy fats from foods such as avocado, nuts and oily fish
  • Maintain a moderate weight: Excess body fat slows the body’s ability to remove LDL cholesterol.
  • Doing regular exercise: Regular exercise can help a person maintain a moderate weight.
  • Quit smoking, if applicable: Smoking damages blood vessels and leads to hardening and stiffening of the arteries, increasing the risk of cardiovascular disease.
  • Avoiding or limiting alcohol: Alcohol can contribute to elevated cholesterol levels.

According to a 2019 study, people with undiagnosed FH have a life expectancy about 16 years lower than those diagnosed with FH. The most likely cause of death is a cardiac event due to a buildup of cholesterol in the arteries.

The outlook for a person with FH also depends on the form of the condition they have. People with heterozygous FH inherit a genetic FH mutation from one biological parent. According to the National Organization for Rare Disorders, people with heterozygous FH have a 10- to 20-fold increased risk of developing CAD.

Individuals with homozygous FH inherit a genetic FH mutation from both biological parents and tend to develop symptoms in childhood. Without treatment, these individuals are at risk of death before the age of 30.

That’s why it’s important for people to discuss their cholesterol levels with a doctor. This is especially true for people with a family history of FH and for those with other risk factors for high cholesterol.

High cholesterol can have several causes. One possible cause is the genetic disorder familial hypercholesterolemia. People with this condition have a genetic mutation that interferes with their body’s ability to remove cholesterol from the blood. This can lead to cardiovascular disease and an increased risk of heart attacks.

People with FH can make certain dietary and lifestyle changes to control their cholesterol, but will likely also need to take cholesterol-lowering drugs, such as statins and PCSK9 inhibitors.

A person concerned about their cholesterol levels should talk to their doctor, especially if they have a personal or family history of high cholesterol or other risk factors for high cholesterol.

Genetics and High Cholesterol: Link, Risks, and More

Leave a Reply

Your email address will not be published.

Scroll to top