High cholesterol can cause the arteries to narrow, leading to serious complications, such as heart disease, heart attack, and stroke. Lowering high cholesterol can help prevent complications.

High cholesterol can lead to excess cholesterol in the blood, which can cause a buildup of fatty deposits, or plaque, in the arteries.

This leads to atherosclerosis, in which the arteries become narrow and stiff, reducing blood flow around the body. This can lead to many severe or life threatening health problems.

This article looks at some of the possible complications of high cholesterol, tips to lower cholesterol and reduce the risk of complications, and when to contact a doctor.

A woman with high cholesterol holding her chest and feeling symptoms of complications, such as angina.-1Share on Pinterest
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Narrowing of the arteries due to plaque can reduce blood flow to the heart. This can cause angina, which involves chest pain that worsens with exertion.

Angina can be a symptom of an underlying problem with the heart, such as coronary heart disease (CHD).

High cholesterol can cause plaque to build up in the walls of the arteries, causing them to become narrower. Narrowed arteries make it more difficult for blood to flow through the arteries and around the body.

This can lead to coronary artery disease, which is a buildup of plaque in the arteries that supply blood to the heart. This reduces blood flow to the heart, reducing the amount of oxygen to the heart muscle.

Coronary heart disease occurs as a result of coronary artery disease, although some healthcare professionals may use these terms interchangeably.

Cardiac events are the biggest risk of high cholesterol levels. If plaque continues to build up within the coronary arteries, coronary heart disease can lead to a block of blood flow to the heart, resulting in a heart attack.

Some people may not have any symptoms of coronary heart disease until they experience a heart attack.

If people have any symptoms of a heart attack, or if they are unsure if chest pain is a heart attack or not, they should call 911.

Is it a heart attack?

Heart attacks occur when there is a lack of blood supply to the heart. Symptoms include:

  • chest pain, pressure, or tightness
  • pain that may spread to arms, neck, jaw, or back
  • nausea and vomiting
  • sweaty or clammy skin
  • heartburn or indigestion
  • shortness of breath
  • coughing or wheezing
  • lightheadedness or dizziness
  • anxiety that can feel similar to a panic attack

If someone has these symptoms:

  1. Dial 911 or the number of the nearest emergency department.
  2. Stay with them until the emergency services arrive.

If a person stops breathing before emergency services arrive, perform manual chest compressions:

  1. Lock fingers together and place the base of hands in the center of the chest.
  2. Position shoulders over hands and lock elbows.
  3. Press hard and fast, at a rate of 100 to 120 compressions per minute, to a depth of 2 inches.
  4. Continue these movements until the person starts to breathe or move.
  5. If needed, swap over with someone else without pausing compressions.

Use an automated external defibrillator (AED) available in many public places:

  1. An AED provides a shock that may restart the heart.
  2. Follow the instructions on the defibrillator or listen to the guided instructions.

If too much plaque builds up in the arteries, it can block a pathway to the brain and prevent blood from reaching the brain, causing a stroke.

Atherosclerosis, which can occur due to high cholesterol, can cause an ischemic stroke in two ways:

  • Atherothrombotic stroke: If plaque breaks off from the blood vessel wall, a blood clot can form. If the clot becomes large enough, it can block blood flow to the brain and cause a stroke.
  • Embolic stroke: If a blood clot forms, it can break away from the original site and travel to an artery connecting to the brain. This can block blood flow and cause a stroke.

High cholesterol increases the risk of peripheral artery disease (PAD). PAD is a narrowing of the arteries that reduces blood flow to the legs. The main cause of PAD is atherosclerosis.

PAD causes pain or aching in the legs during physical activity, which eases with rest. Other symptoms affecting the legs include:

Excessive plaque buildup in the peripheral arteries of the legs may cause a blockage that, without treatment, may lead to complete loss of blood flow to the legs. This may result in gangrene or the loss of a limb.

Lowering low-density lipoprotein (LDL) cholesterol can help reduce the risk of complications, such as those above. Tips to help reduce cholesterol levels include:

  • reducing saturated and trans fats
  • focusing on eating plant foods, such as whole grains, legumes, and nuts, which contain stanols and sterols that help reduce cholesterol
  • including healthy fats, such as olive and avocado oils
  • increasing soluble fiber intake
  • getting regular physical activity
  • maintaining a moderate weight, as a weight loss of 5% to 10% may help improve cholesterol levels
  • avoiding or quitting smoking

Learn more about reducing cholesterol.

The American Heart Association (AHA) recommends all adults over 20 years old test their cholesterol levels every 4 to 6 years. If people have the following risk factors, they may need more frequent testing.

  • high blood pressure
  • older age
  • obesity
  • family history of high cholesterol

When people reach 40 years of age, people can also speak with a doctor to calculate their 10-year heart attack or stroke risk.

High cholesterol generally has no symptoms until it causes a complication or health problem. A doctor can perform a blood test to find out a person’s cholesterol levels.

People with high cholesterol can discuss a treatment plan with a doctor to effectively lower their cholesterol levels. If lifestyle changes are not enough to reduce cholesterol, a doctor may prescribe cholesterol-lowering medication, such as statins.

People should also seek immediate medical attention if they have symptoms of a stroke or heart attack. These events are medical emergencies.

Without treatment, high cholesterol can cause serious complications. High cholesterol causes a buildup of plaque in the arteries, which causes them to narrow and harden.

This reduces blood flow and increases the risk of blood clots, which can lead to conditions, such as coronary heart disease, peripheral artery disease, heart attack, and stroke.

Diet and lifestyle changes can help prevent and treat high cholesterol. Some people may also need cholesterol-lowering medication.