Risk, causes, and prevention of ischaemic stroke in elderly patients with symptomatic internal-carotid-artery stenosis

Background Carotid endarterectomy benefits patients with symptomatic stenos is of 70-99% in the internal carotid artery, with smaller benefit for 50-69 % stenosis. The benefit of carotid endarterectomy in patients of 75 years a nd older remains unclear. Methods American Symptomatic Carotid Endarterectomy Trial were compared wit h those aged 65-74 years and less than 65 years for baseline characteristic s and risk of ipsilateral ischaemic stroke at 2 years by degree of stenosis and treatment group. Patients aged 75 years pr older from the North Sympto matic Carotid Endarterectomy Trial: were Findings Among patients with 70-99% stenosis, the absolute risk reduction o f ipsilateral ischaemic stroke with carotid endarterectomy was 28.9% (95% C I 12.9-44.9) for patients aged 75 years or older (n=71), 15.1% (7.2-23.0) f or those aged 65-74 years (n=285), and 9.7% (1.5-17.9) for the youngest gro up (n=303). Among patients with 50-69% stenosis, the absolute risk reductio n was significant only in those of 75 years and older (n=145; 17.3% [6.6-28 .0]). The perioperative risk of stroke and death at any degree of stenosis was 5.2% for the oldest group, 5.5% for 65-74 years, and 7.9% for less than 65 years. The number of patients aged 75 years or older needed to treat to prevent one ipsilateral stroke within 2 years was three with 70-99% stenos is and six with 50-69% stenosis. Interpretation In the prevention of ipsilateral ischaemic stroke, elderly p atients with 50-99% symptomatic carotid stenosis benefited more from caroti d endarterectomy than younger patients did. To achieve this treatment benef it, surgeons must be skilled and patients with other life-threatening illne sses must be excluded.