Abbreviated DAPT regimen more beneficial to women compared to men: JAMA

The researchers found that bleeding and ischemic risks were comparable between sexes in the prespecified comparative effectiveness analysis of the MASTER-DAPT trial comprising 4579 participants. They found no significant interaction between net bleeding and adverse events, while a significant heterogeneity was seen for major adverse cardiac or cerebral events (MACCE) with the benefit of abbreviated DAPT in women but not in men.

Abbreviated DAPT reduces bleeding with no increase in ischemic events in patients at HBR undergoing percutaneous coronary intervention (PCI). Antonio Landi, Ente Ospedaliero Cantonale, Lugano, Switzerland, and colleagues aimed to evaluate the association of sex with the comparative effectiveness of abbreviated vs standard DAPT in patients with high bleeding risk.

The study was an analysis of the MASTER DAPT trial, a randomized, multicenter, open-label clinical trial conducted at 140 sites in 30 countries and performed from 2017 to 2019. 4579 patients with HBR were randomized at 1 month after PCI to abbreviated or standard DAPT. They were randomized to abbreviated (immediate DAPT discontinuation, followed by single APT for ≥6 months) or standard (DAPT for ≥2 additional months, followed by single APT for 11 months) treatment groups.

Based on the study, the researchers reported the following:

• Of the 4579 patients included in the analysis, 30.7% were women and 69.3% were men (mean age, 76.0 years).
• Ischemic and bleeding events were similar between the sexes. Abbreviated DAPT was associated with comparable net adverse clinical events (NACE) rates in men (hazard ratio [HR], 0.97) and women (HR, 0.87).
• There was evidence of heterogeneity of treatment effect by sex for MACCEs, with a trend toward benefit in women (HR, 0.68) but not in men (HR, 1.17).
• There was no significant interaction for nonmajor bleeding (MCB) across sexes, although the benefit with abbreviated DAPT was relatively greater in men (HR, 0.65) than in women (HR, 0.77).
• Results remained consistent in patients with acute coronary syndrome and/or complex PCI.

"We showed that female patients with high bleeding rates did not have higher risks of ischemic and bleeding events compared with male patients despite several differences in baseline characteristics," the researchers wrote.

"Abbreviated DAPT benefits over standard DAPT remained generally consistent in both sexes, albeit women may derive enhanced benefit from an abbreviated DAPT regimen owing to numerically lower bleeding and ischemic events rate."

"The latter findings should be regarded as exploratory and need prospective validation," they concluded.

Reference:

Landi A, Alasnag M, Heg D, et al. Abbreviated or Standard Dual Antiplatelet Therapy by Sex in Patients at High Bleeding Risk: A Prespecified Secondary Analysis of a Randomized Clinical Trial. JAMA Cardiol. Published online November 22, 2023. doi:10.1001/jamacardio.2023.4316