Conference Coverage

Early aspirin withdrawal after PCI: More benefit for women?


A new analysis from the TWILIGHT study has shown that, in the high-risk population undergoing percutaneous coronary intervention (PCI) enrolled in the study, the benefits of early aspirin withdrawal and continuation on ticagrelor monotherapy were similar in women and men.

But there were some interesting observations in the analysis suggesting possible additional benefits of this strategy for women.

“These data support the use of ticagrelor monotherapy in women and men, and importantly show that the absolute risk reduction of bleeding was higher in women, as their bleeding rates were higher,” senior author Roxana Mehran, MD, the Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, said in an interview.

“These data also support the need for prospective dual antiplatelet therapy deescalation studies in women,” Dr. Mehran added.

The main results of the TWILIGHT study showed that after a short period of dual antiplatelet therapy, a strategy of ticagrelor monotherapy, compared with continued dual therapy led to reduced bleeding without an increase in ischemic events among patients at high risk for bleeding or ischemic events after PCI.

The new gender-based analysis was presented by Birgit Vogel, MD, on May 15 at the annual scientific sessions of the American College of Cardiology. It was also published online in JAMA Cardiology to coincide with the ACC presentation.

Dr. Vogel, also from Wiener Cardiovascular Institute, explained that the current analysis was undertaken to investigate whether the TWILIGHT results varied in relation to sex, given that women are believed to have an increased risk for bleeding after PCI, compared with men.

“The current analysis showed that, while women did have a higher bleeding risk, compared to men, this was no longer significant after adjustment for baseline characteristics; and ischemic events were similar between the two sexes,” she reported.

“Results showed that withdrawing aspirin while continuing ticagrelor after 3 months of dual antiplatelet therapy was associated with a reduction in bleeding and preserved ischemic benefits in both women and men,” she added.

The TWILIGHT trial randomized 7,119 patients at high risk of ischemic or bleeding events who had undergone successful PCI with at least one drug-eluting stent and had completed 3 months of dual antiplatelet therapy to aspirin or placebo for an additional 12 months plus open-label ticagrelor.

The main results showed that the primary endpoint of Bleeding Academic Research Consortium (BARC) 2, 3, or 5 bleeding at 1 year was almost halved with ticagrelor monotherapy, occurring in 4% of these patients, compared with 7.1% of the ticagrelor/aspirin group (hazard ratio, 0.56). Ischemic events were similar in the two groups.

The current analysis focused on whether these effects varied in relation to sex.

Dr. Vogel noted that women made up 23.9% of the study population, were older than the men, and were more likely to have diabetes, chronic kidney disease, anemia and hypertension, while the men were more likely to be current smokers. Men had a higher incidence of coronary heart disease history, while women were more likely to have an ACS indication for PCI.

Unadjusted results showed a higher rate of BARC 2, 3, or 5 bleeding at 1 year in women (6.8%) versus men (5.2%), giving an HR of 1.32 (95% CI, 1.06-1.64).

But after adjustment for baseline characteristics, this became nonsignificant (HR, 1.20; 95% CI, 0.95-1.52).

Dr. Vogel pointed out that the most severe type of bleeding (BARC 3 and 5) was not attenuated as much by adjustment for baseline characteristics, with the HR reducing from 1.57 to 1.49.

The ischemic endpoint of death/stroke or MI was similar in men (4.0%) and women (3.5%), and this did not change after adjustment for baseline characteristics.

In terms of the two treatment groups, BARC 2, 3, or 5 bleeding was reduced to a similar extent with ticagrelor monotherapy in both men and women. This endpoint decreased from 8.6% in women on dual-antiplatelet therapy to 5.0% in women on ticagrelor alone (adjusted HR, 0.62) and from 6.6% to 3.7% in men (aHR, 0.57). But she noted that the absolute risk reduction in bleeding was greater in women (3.6%) versus men (2.9%).

“If we have a relative risk reduction in bleeding with early withdrawal of aspirin that is similar between the sexes but an overall higher risk of bleeding in women, that results in a greater absolute risk reduction,” Dr. Vogel commented.

The primary ischemic endpoint of death/MI/stroke was not increased in the ticagrelor group vs the dual antiplatelet group in either men (aHR, 1.06) or women (aHR, 1.04).


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