Objective: To determine whether carotid endarterectomy prevents deterioration of functional status among patients with transient ischemic attacks or nondisabling strokes and ipsilateral carotid stenosis of 70% to 99%.
Design: Multicentered randomized controlled trial with an average 18-month follow-up.
Setting: Fifty clinical centers in North America.
Patients: A total of 659 patients presenting with recent transient attacks of nondisabling stroke and ipsilateral atherosclerotic carotid stenosis of 70% to 99% were included. Patients were stable neurologically at the time of entry. No patient was lost to follow-up.
Intervention: Vascular surgeons and neurosurgeons were prescreened for low perioperative complication rates. Patients were randomly allocated to carotid endarterectomy plus continuing medical care (n = 328) or medical care alone (n = 331), including antiplatelet therapy.
Main outcome measures: All patients were assessed by neurologists for the occurrence of stroke and functional status at scheduled intervals after entry.
Results: In addition to a previously reported risk reduction for ipsilateral stroke for patients assigned to carotid endarterectomy, there was an absolute risk reduction (and relative risk reduction [RRR]) for functional status impairment of 5.6% (RRR, 69%) for vision, 4.6% (RRR, 87%) for comprehension of language, 8.3% (RRR, 88%) for fluency of speech, 4.3% (RRR, 84%) for swallowing, 6.0% (RRR, 53%) for lower-limb function, 9.3% (RRR, 75%) for upper-limb function, 7.4% (RRR, 60%) for shopping, and 10.5% (RRR, 50%) for visiting outside usual residence (P < .05, two-tailed, for all items).
Conclusions: Carotid endarterectomy reduced the risk for impairment of function among patients with recent symptomatic cerebral ischemia and ipsilateral high-grade carotid stenosis.