Atherosclerosis Causes and Risk Factors

Risk factors are conditions or habits that make a person more likely to develop a disease. Nearly half of Americans have high blood pressure or unhealthy cholesterol levels, or they smoke. These are key risk factors that can trigger the start of plaque buildup.

What causes atherosclerosis?

Plaque buildup in the arteries starts with damage to the arteries. Risk factors such as unhealthy lifestyle habits, medical conditions, or your genes, can lead to this damage.

This video shows how buildup of cholesterol and other waste can lead to plaque buildup (atherosclerosis). Medical Animation Copyright © 2022 Nucleus Medical Media Inc. All rights reserved

inflammatory cells travel to the damaged areas of the artery and release chemical signals. The signals cause cholesterol and cell waste to collect at the damaged spots. This buildup attracts white blood cells that eat the cholesterol and clump together, forming plaque. The artery narrows as the plaque grows, reducing the flow of oxygen-rich blood to the limbs and organs. Over time, the plaque can break and flow into the bloodstream. This may lead to formation of blood clots, which can block blood flow. If this happens, nearby tissue can't get enough oxygen and may die. 

What raises the risk of atherosclerosis?

The risk factors for plaque buildup are often linked. For example, smoking and a lack of regular physical activity raises your risk of unhealthy levels of cholesterol, which can lead to plaque buildup.

Other common risk factors for plaque buildup are listed below.

  • High blood pressure: Over time, high blood pressure can damage artery walls, allowing plaque to build up.
  • Diabetes: High blood sugar can damage the inner layers of the arteries, causing plaque buildup.
  • Metabolic syndrome: High levels of cholesterol and triglycerides in your blood increase your risk.
  • Unhealthy diet: Eating a lot of foods high in saturated fats can increase your cholesterol levels.
  • Family history: Your gene may increase your risk, especially if you have a common inherited cholesterol disorder called familial hypercholesterolemia.
  • Inflammatory diseases: When you have conditions such as rheumatoid arthritis and psoriasis, high levels of inflammation can end up irritating your blood vessels, which can lead to plaque buildup.   
  • Older age: For most people, plaque buildup starts in childhood and gets worse as they get older. In men, the risk increases after age 45. In women, the risk increases after age 55. The risk for women is even higher if you have endometriosis or polycystic ovary syndrome, or if you had gestational diabetes or preeclampsia during pregnancy.

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Did you know that heart disease is the number one killer of women of all ages, races, shapes, and sizes in the United States? Learn more on our webpage dedicated to heart disease in women.

What should you do if you have risk factors?

Talk with your healthcare team about your heart health. Together, you can set up a plan to reduce your risk, monitor your health, and manage your risk factors to delay or prevent disease caused by atherosclerosis. Starting treatment early is the key to preventing symptoms.

Research for your health

The NHLBI leads and supports research to better understand what raises the risk of atherosclerosis and also how it is linked to other medical conditions. One study, for example, found that psoriasis can raise the risk of metabolic syndrome and atherosclerosis.


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