Should I be screened for carotid artery narrowing?

What the USPSTF recommends

The 2021 statement reaffirms the 2014 recommendation. The USPSTF concluded with moderate certainty that the harms of screening adults without symptoms outweigh the benefits (USPSTF 2021). Clinicians should still watch for signs and symptoms and check them when they appear (USPSTF 2021).

What carotid narrowing is

Carotid artery stenosis is a narrowing of the arteries in the neck caused by atherosclerosis. It is a risk factor for stroke and a marker of higher heart attack risk, but it causes a fairly small share of strokes (USPSTF 2021). In the general population it is uncommon, about 0.5% to 1%, and it becomes more common with age (USPSTF 2021).

What about risk factors?

Older age, male sex, high blood pressure, smoking, high cholesterol, diabetes and heart disease all raise the chance of carotid narrowing (USPSTF 2021). The trials the USPSTF reviewed included people with these risk factors, and it still found no benefit in screening people without symptoms. No reliable tool can say who has important narrowing, or whose narrowing will cause a stroke (USPSTF 2021).

Why screening does more harm than good

Neck ultrasound finds 70% or greater narrowing fairly well, but in the general population, where narrowing is rare, it gives many false-positive results (USPSTF 2021). No studies looked directly at whether screening improves health (USPSTF 2021). A positive result can lead to more tests and to surgery. In the older trials, 0.4% to 1.2% of people who had angiography to confirm the result had a stroke because of it, and about 2.4% of people who had carotid surgery (endarterectomy) died or had a stroke within 30 days. In large recent registries, 30-day stroke or death ranged from 1.4% to 3.5% after endarterectomy and from 2.6% to 5.1% after stenting (USPSTF 2021). For people without symptoms, the harms of surgery compared with good medical care appear to outweigh the benefits (USPSTF 2021).

Listening to the neck with a stethoscope for a bruit is not accurate enough to be a screening test (USPSTF 2021).

Common questions

Do other groups agree?

Not all. The American Heart Association and American Stroke Association also advise against routine ultrasound screening in people without symptoms. Some professional societies say screening is reasonable for people with a bruit heard in the neck, with several stroke risk factors, or with known artery disease elsewhere (USPSTF 2021).

How is carotid narrowing treated if it is found?

Treatment usually targets atherosclerosis as a whole: statins, antiplatelet medicines, blood pressure and diabetes control, and lifestyle changes. Surgery or stenting can be added in some cases (USPSTF 2021).

Also see the stroke risk check, the statin check, the blood pressure screening check, the aortic aneurysm screening check, the peripheral artery disease screening check andaortic aneurysm screening check and all screening tests by age.