Peripheral artery disease risk factors: what raises the risk and what lowers it

What PAD is

Peripheral arterial disease in the legs is the narrowing or blockage of the vessels that carry blood from the heart to the legs. It is mainly caused by a buildup of fatty plaque in the arteries, called atherosclerosis (CDC). Plaque is made up of fat, cholesterol, fibrous tissue and calcium, and it can reduce or fully block the flow of oxygen-rich blood (NHLBI). If blocked blood flow is severe enough, it can cause tissue death and sometimes lead to amputation of the foot or leg (MedlinePlus).

Approximately 6.5 million people age 40 and older in the United States have PAD (CDC). People with PAD are also at risk for coronary artery disease and cerebrovascular disease, which could lead to a heart attack or stroke (CDC).

Risk factors that raise the risk

The risk factors for PAD are mostly the same as those for coronary heart disease and carotid artery disease, which are also caused by atherosclerosis (NHLBI).

• Smoking. MedlinePlus calls smoking the main risk factor (MedlinePlus). Smoking or regularly breathing in secondhand smoke damages blood vessels, raises blood pressure and causes unhealthy cholesterol levels, and nicotine makes blood vessels tighten and reduces blood flow in the legs (NHLBI).
• Age. You can develop PAD at any age, but the risk goes up as you get older. Most people in the United States who have PAD are age 65 or older (NHLBI). The CDC lists age above 60 years (CDC).
• Diabetes (NHLBI) (CDC).
• High blood pressure (NHLBI) (CDC).
• High cholesterol or high triglycerides (NHLBI) (CDC).
• Chronic kidney disease (NHLBI).
• Obesity and metabolic syndrome (NHLBI).
• Heart disease and stroke (MedlinePlus).
• Family history. A family history of PAD, heart disease, stroke, or blood vessel disease such as some types of vasculitis raises the risk (NHLBI).
• Pregnancy history. Having had preeclampsia or gestational diabetes during pregnancy raises the risk of PAD later in life (NHLBI).
• Lifestyle habits. Not getting enough physical activity can make other risk factors worse, stress can make arteries tighten and narrow, and eating foods high in saturated fat can raise the risk (NHLBI).
• Other conditions. Disorders that cause blood clots, such as thrombocytosis or antiphospholipid syndrome, and fibromuscular dysplasia (NHLBI).

Race, ethnicity and sex

African American people have a higher risk of PAD than people of other races or ethnicities, and are more likely to have complications such as problems walking or loss of a limb. American Indian women have a higher risk than white or Asian American women (NHLBI). Men and women have a similar risk, but women are more likely to have PAD without symptoms and often have more complications, such as problems walking (NHLBI).

Which ones you can change

NHLBI suggests heart-healthy lifestyle changes: quitting smoking, a heart-healthy eating pattern such as the DASH eating plan, being physically active, aiming for a healthy weight and managing stress, plus following your provider's advice on diabetes, high blood pressure and high blood cholesterol (NHLBI). The CDC adds that physical activity can help prevent PAD or improve its symptoms, and that smoking makes PAD symptoms worse (CDC).

The PAD risk calculator estimates the 4-year chance of leg pain from PAD for ages 45 to 84, using the Framingham model. Because PAD shares its risk factors with heart disease, heart disease risk factors are worth reading too, and so are abdominal aortic aneurysm risk factors, since PAD is one of them.

Leg signs to report

About 1 in 4 people with PAD have the common symptoms, more than half have nontypical symptoms, and about 1 in 5 do not report any symptoms (NHLBI). The CDC says up to 4 in 10 people with PAD have no leg pain (CDC). Signs include (NHLBI) (CDC):

• Pain, aching, heaviness or cramping in the legs that comes when walking or climbing stairs and goes away after rest (intermittent claudication), often in the calf but also the buttocks, hip or thigh
• One foot or leg colder than the other
• Pale, discolored or blue skin on the foot or leg; smooth, shiny skin
• Toenails and leg hair that stop growing
• Weak or absent pulses in the feet
• Leg weakness or numbness, or cold or numb toes
• Sores or wounds on the toes, feet or legs that heal slowly or not at all

MedlinePlus also lists erectile dysfunction, especially in men who have diabetes (MedlinePlus). Pain in the leg and foot at rest can be a sign of severe PAD (NHLBI). Without treatment, PAD may cause sores, infections and even the loss of a limb (NHLBI), so tell your provider about these signs. Other conditions can mimic PAD symptoms (CDC).

Is there a screening test?

If you have symptoms, your doctor may do an ankle-brachial index (ABI), a noninvasive test that compares the blood pressure in the ankles with the blood pressure in the arms (CDC). For adults without symptoms, the US Preventive Services Task Force found the evidence insufficient to weigh the benefits and harms of screening with the ABI (I statement) (USPSTF 2018). The PAD screening check explains what it means for you.

Common questions

Can I have PAD without leg pain?

Yes. Many people who have PAD do not have any symptoms (MedlinePlus), and up to 4 in 10 have no leg pain (CDC).

Why does PAD matter for my heart?

It comes from the same plaque buildup as coronary heart disease. PAD can raise the risk of heart attack, stroke and transient ischemic attack (MedlinePlus), and no matter the symptoms, everyone with PAD shares the same high risk of cardiovascular disease (NHLBI).

What is the most important change I can make?

If you smoke, quitting. NHLBI calls quitting smoking a very important step in lowering your risk of PAD (NHLBI).