Do women bleed more than men when prescribed novel oral anticoagulants for venous thromboembolism? A sex-based meta-analysis.
BACKGROUND
Bleeding complications occur more frequently in women than men in clinical trials of warfarin and thrombolytics. It is unknown whether these sex-related differences exist for new oral anticoagulants, including dabigatran, rivaroxaban, and apixaban. To determine whether women suffer more bleeding complications with these agents, we conducted a systematic review and meta-analysis of randomized controlled trials on new oral anticoagulants for venous thromboembolism (VTE).


METHODS
Medline, Embase, and the Cochrane-controlled trial register on the Cochrane library were searched to identify studies that evaluated novel oral anticoagulants versus any comparator, and reported outcomes, including major bleeding and recurrent VTE, stratified by sex. No language restrictions were applied. Studies were evaluated according to a priori inclusion criteria and critically appraised using established internal validity criteria. Pooled relative risk was estimated using a random effects model.


RESULTS
Eight studies were eligible, comprising 9417 patients. There was no difference in the primary efficacy outcome of recurrent VTE between men and women [Relative Risk (RR) 1.02, 95% confidence interval (CI) 0.74-1.39]. However, men had less major bleeding with novel oral anticoagulants compared to women [RR 0.79, 95% CI 0.66-0.97, p=0.03]. All-cause mortality was not reported by sex in any of the studies.


CONCLUSIONS
Women suffer more bleeding complications than men when receiving novel oral anticoagulants for VTE. Future clinical trials should report outcomes stratified by sex, and further studies are needed to investigate the clinical impact of this sex-related safety difference.
Department of Medicine, University of Alberta, Canada.
Ghazi S
GS
Alotaibi
Hind
H
Almodaimegh
M Sean
MS
McMurtry
Cynthia
C
Wu
D000284:Administration, Oral; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects*; D005260:Female; D006470:Hemorrhage / Q000097:blood / Q000139:chemically induced*; D006801:Humans; D008297:Male; D016032:Randomized Controlled Trials as Topic; D012737:Sex Factors; D054556:Venous Thromboembolism / Q000097:blood* / Q000188:drug therapy*
D000925:Anticoagulants
Bleeding; Novel oral anticoagulants; Sex-related differences; Venous thromboembolism