“…NOAC comparisons report slightly different bleeding rates for each agent against LMWH (usually enoxaparin) and among them. A synthesis includes: major bleeding in 1.4% (220 mg) or 1.1% (150 mg) vs. 1.4% (3 trials and 8,135 patients in dabigatran vs enoxaparin 251 ,); major or non-major, clinically relevant bleeding RR vs. enoxaparin of 1.52 (ribaroxaban), 0.34 (betrixaban), 0.88 (apixaban), 0.85 (darexaban), 1.30 (edoxaban) 250 ; better preventive effects on bleeding with apixaban 252 ; RR of major bleeding of oral direct factor Xa inhibitors vs. enoxaparin, 1.27 (5 trials, 12,184 patients with THA) and 0.94 (5 trials, 13,169 patients with TKA) being non significantly different from enoxaparin 253 ; less bleeding (and less efficacy) of enoxaparin vs. immediately postop ximegalatran with hip odds ratio (OR) = 0.30 and knee OR = 0.71 (6 trials, 10,051 THA or TKA patients) 254 ; compared to enoxaparin, the RR of clinically significant risk of bleeding was higher with rivaroxaban (RR = 1.25), similar with dabigatran (RR = 1.12) and lower with apixaban (RR = 0.82) in a meta-analysis of 16 trials, 38,747 THA or TKA patients 256 ; compared with dabigatran, enoxaparin similarly efficacious and similar risk of bleeding (OR = 0.90), while compared with rivaroxaban, enoxaparin less efficacious but lower risk of bleeding (OR = 0.79) in a meta-analysis with 6 trials, 18,405 THA or TKA patients 257 ; in a network meta-analysis with 19 trials and 43,838 THA or TKA patients, OR were also calculated against enoxaparin 30 mg twice a day ( bis in die [bid]) or 40 mg daily, and bleeding (major/non-major clinically relevant) was significantly increased for fondaparinux (vs. 40 mg daily, OR = 0.67) and rivaroxaban (vs. 40 mg daily, OR = 0.77) 258 , while apixaban as the comparator (2.5 mg bid) showed increased bleeding with enoxaparin 30 mg bid (OR = 0.75), dabigatran (OR = 0.73), fondaparinux (OR = 0.56), and rivaroxaban (OR = 0.65); a meta-analysis with 21 randomized control trials (RCT) 259 produced major bleeding rates with enoxaparin of 1.32%, dabigatran 1.25%, rivaroxaban 2.02%, apixaban 0.70%, ximegalatran 0.93%; a pooled analysis of 2 RCT with 8,464 THA or TKA patients comparing apixaban and enoxaparin showed a major bleeding rate of 0.7% and 0.8%, but when non-major clinically relevant bleeding was summed, the rates were 4.4% for apixaban and 4.9% for enoxaparin 260 . As a summary, major bleeding rates for enoxaparin were reported from 0.8 to 1.3%, for dabigatran 1.1 to 1.4%, for apixaban around 0.7, for rivaroxaban around 2%.…”