Sex and outcomes after stenting and endarterectomy in asymptomatic severe carotid stenosis patients

Objectives: To determine if sex was an effect modifier in a pooled analysis of asymptomatic patients from CREST and ACT I. Materials and Methods: We analyzed data from 2544 patients aged <80 with >= 70 % asymptomatic carotid stenosis randomized to CAS or CEA (nCREST = 1091; nACT-1 = 1453). The pre-specified primary endpoint in both trials was any stroke, myocardial infarction or death during the peri-procedural period, or ipsilateral stroke within 4 years of randomization. The secondary endpoint was any stroke or death during the peri-procedural period, or ipsilateral stroke within 4 years of randomization. Results: There was no significant difference in the frequency of events for men or women between CAS and CEA for the primary or secondary endpoints. When assessing for an interaction of sex and risks between procedures, the treatment-by-sex interaction was not significant for either primary or secondary endpoints in the four-year period or the peri-procedural period. However, women had significantly fewer post-procedural events (ipsilateral stroke) with CAS than CEA (HR = 0.33, 95 % CI: 0.09-1.18) compared to men (HR = 2.09, 95 % CI: 0.78-5.61), p = 0.02 for interaction. Conclusions: In this large, pooled analysis of asymptomatic patients comparing CAS to CEA, sex did not act as an effect modifier of treatment differences in the four-year primary stroke-MI-or-death endpoint or the secondary stroke-or-death endpoint. However, during the post-procedural period men treated with CAS were at higher risk than their female counterparts.