In the CAS group , recurrent stroke or transient ischemic attack occurred more often among DWI + patients ( 12 of 62 ) than among DWI - patients ( 6 of 62 ) , with a cumulative 5-year incidence of 22.8 % ( standard error [ SE ] : 7.1 % ) and 8.8 % ( SE : 3.8 % ) , respectively ( unadjusted hazard ratio : 2.85 ; 95 % confidence interval : 1.05 to 7.72 ; p = 0.04 ) .