In a recommendation statement published on 2 February in The Journal of the American Medical Association (JAMA), the US Preventive Services Task Force (USPSTF) advises against screening for asymptomatic carotid artery stenosis in the general adult population. This recommendation is consistent with the task force’s 2014 statement on the topic.
During a review of all the available data on screening for carotid artery stenosis in the general population, authors Alex H Krist (Virginia Commonwealth University, Richmond, USA) and colleagues detail that the USPSTF “found no new substantial evidence” that could change its 2014 recommendation. Therefore, the statement concludes “with moderate certainty that the harms of screening for asymptomatic carotid artery stenosis outweigh the benefits”.
The authors detail that asymptomatic carotid artery stenosis refers to stenosis in persons without a history of ischaemic stroke, transient ischaemic attack, or other neurologic symptoms referable to the carotid arteries.
The prevalence of asymptomatic carotid artery stenosis is low in the general population but increases with age, Krist et al note, adding that, while asymptomatic carotid artery stenosis is a risk factor for stroke and a marker for increased risk for myocardial infarction, it causes a relatively small proportion of strokes.
Although the USPSTF do not recommend screening of the general population for asymptomatic carotid artery stenosis, the authors acknowledge that several risk factors increase a person’s risk, including older age, male sex, hypertension, smoking, hypercholesterolaemia, diabetes, and heart disease. However, they also state that “there are no externally validated, reliable methods to determine who is at increased risk for carotid artery stenosis, or who is at increased risk for stroke when carotid artery stenosis is present”.
Krist and colleagues highlight data gaps in this field, writing: “More research is needed to evaluate the benefits and harms of screening for asymptomatic carotid artery stenosis in the general adult population.”
Considering the direction of future research, they suggest that this would include trials with long-term follow-up (>5 years) that compare carotid endarterectomy (CEA) or carotid artery angioplasty and stenting (CAS) plus contemporary best medical therapy with best medical therapy alone, including completion of ongoing trials.
In addition, they recommend the development and validation of tools to determine which persons are at high risk for carotid artery stenosis and for stroke due to carotid artery stenosis and who might experience harm from treatment with CEA or CAS.