COMPARISON AND METAANALYSIS OF RANDOMIZED TRIALS OF ENDARTERECTOMY FOR SYMPTOMATIC CAROTID-ARTERY STENOSIS

Objective: Comparison and meta-analysis of randomized trials of caroti d endarterectomy for symptomatic stenosis of the extracranial carotid artery. Background: Randomized trials (North American Symptomatic Caro tid Endarterectomy Trial [NASCET], the European Carotid Surgery Trial [ECST], and the VA Cooperative Study [VACS]) each show that carotid en darterectomy improves outcomes in selected symptomatic patients with h igh-grade extracranial carotid artery stenosis. Direct comparisons amo ng the studies have not been possible because of differing methodologi es, endpoints, and formats of data reporting. Design/methods: Data for specified endpoints and corresponding person-years at risk were obtai ned for each trial. The rates of nonfatal stroke, nonfatal myocardial infarction, or death for surgically or medically treated patients in t he perioperative period (30 days) and thereafter were compared (both i ncluding and excluding perioperative events) and then combined using m eta-analytic techniques. Data from NASCET and ECST were also analyzed for differences in outcomes by sex. Results: Event rate estimates (wit h 95% confidence intervals [95% CI]) for the first 30 days (events per person-year, primarily nonfatal stroke) for medically treated patient s were 0.44 (0.22 to 0.76) for NASCET, 0.15 (0.04 to 0.38) for ECST, a nd 0.27 (0.03 to 0.96) for VACS. For surgically treated patients, the corresponding rates (per person-year) were 0.78 (0.49 to 1.19), 0.63 ( 0.41 to 0.94), and 1.27 (0.58 to 2.43). Event rates per year after 30 days were higher for medically treated patients (0.20 [0.16 to 0.25] v ersus 0.08 [0.05 to 0.11] for NASCET; 0.12 [0.10 to 0.15] versus 0.07 [0.06 to 0.09] for ECST; and 0.15 [0.07 to 0.25] versus 0.07 [0.03 to 0.16] for VACS). There were no significant differences among the trial s, with an overall benefit for surgical therapy (risk ratio estimate, RR = 0.67, 95% CI = 0.54 to 0.83). There were no significant sex-based differences between NASCET and ECST and the overall benefit was not s ignificantly different for men and women (RR = 0.58, 95% CI = 0.45 to 0.74 for men; RR = 0.84, 95% CI = 0.57 to 1.25 for women). Conclusions : Adjusting for primary endpoints and duration of follow-up, carotid e ndarterectomy has a similar benefit for symptomatic patients across tr ials and a similar benefit for men and women.