Recurrent VTE occurred in 31 of 449 patients treated with tinzaparin and 45 of 451 patients treated with warfarin ( 6-month cumulative incidence , 7.2 % for tinzaparin vs 10.5 % for warfarin ; hazard ratio [ HR ] , 0.65 [ 95 % CI , 0.41-1 .03 ] ; P = .07 ) .