Is there Sex-related Outcome Difference According to oral P2Y12 Inhibitors in Patients with Acute Coronary Syndromes? A Systematic Review and Meta-Analysis of 107,126 Patients

Background and Objectives: The majority of patients included in trials of anti-platelet therapy are male. This systematic review and meta-analysis aimed to determine whether, in addition to aspirin, P2Y12 blockade is beneficial in both women and men with acute coronary syndromes. Methods: Electronic databases were searched and nine eligible randomised controlled studies were identified that had sex-specific clinical outcomes (n=107,126 patients). Risk Ratios (RR) and 95% Confidence Intervals (CI) were calculated for a composite of cardiovascular death, myocardial infarction or stroke (MACE), and a safety endpoint of major bleeding for each sex. Indirect comparison analysis was performed to statistically compare ticagrelor against prasugrel. Results: Compared to aspirin alone, clopidogrel reduced MACE in men (RR, 0.79; 95% CI, 0.68 to 0.92; p=0.003), but was not statistically significant in women (RR, 0.88; 95% CI, 0.75 to 1.02, p=0.08). Clopidogrel therapy significantly increased bleeding in women but not men. Compared to clopidogrel, prasugrel was beneficial in men (RR, 0.84; 95% CI, 0.73 to 0.97; p=0.02) but not statistically significant in women (RR, 0.94; 95% CI, 0.83 to 1.06; p=0.30); ticagrelor reduced MACE in both men (RR, 0.85; 95% CI, 0.77 to 0.94; p=0.001) and women (RR, 0.84; 95% CI, 0.73 to 0.97; p=0.02). Indirect comparison demonstrated no significant difference between ticagrelor and prasugrel in either sex. Compared to clopidogrel, ticagrelor and prasugrel increased bleeding risk in both women and men. Conclusion: In summary, in comparison to monotherapy with aspirin, P2Y12 inhibitors reduce MACE in women and men. Ticagrelor was shown to be superior to clopidogrel in both sexes. Prasugrel showed a statistically significant benefit only in men; however indirect comparison did not demonstrate superiority of ticagrelor over prasugrel in women.