PARIS Registry: Sex Disparity in DAPT Cessation Arises from Comorbidities

PARIS, France—Dual antiplatelet therapy (DAPT) cessation is more common for women than men. But findings from a subanalysis of the PARIS registry, presented Wednesday, May 21, 2014, at EuroPCR, indicate that the higher adverse event rates experienced by women who stop their medications are linked not directly to their sex but to their higher overall comorbidity burden.

Researchers led by Roxana Mehran, MD, of Mount Sinai Medical Center (New York, NY), looked at more than 5,000 stented patients on DAPT enrolled in the PARIS registry. They followed patients out to 24 months (93.2%) and noted their antiplatelet treatment as:

• Discontinued: as per recommendation of their physician who felt the patient no longer needed therapy
• Interrupted: on a voluntary basis and as guided by a physician (ie, due to surgery) for no more than 14 days
• Disrupted: due to bleeding or noncompliance

Women were generally older than men and had a greater burden of comorbidity. Nevertheless, there was only a trend toward greater discontinuation in women (P = .051)—with a “bump” at 1 year in both sexes—and no difference in interruption between men and women (P = .31). Disruption, however, was seen more often in women (P < .001).

Higher rates of cardiac death (P = .02), MACE (P = .03), and BARC-defined major bleeding (P < .001) were seen in women than men. There were no differences in definite/probable stent thrombosis or spontaneous MI.

Dr. Mehran explained that disruption of DAPT within 7 days of the procedure was linked with higher risk of MACE in the overall PARIS registry (HR 7.04; 95% CI 3.31-14.95; P < .001). However, there were no associations between DAPT cessation and the composite endpoint of cardiac death, spontaneous MI, and definite/probable stent thrombosis or any of its individual components in the current analysis by sex.

Higher Bleeding in Women May Lead to More Cessation

Since the study is a post hoc analysis, it can be only “hypothesis generating, as usual,” she explained. Another limitation is that “most patients were treated with clopidogrel and this limits our ability to generalize [the findings] to the very important P2Y12 inhibitors. There were very few events after interruption so this could [lead to] an imprecise point estimate for this kind of DAPT cessation,” Dr. Mehran noted.

With regard to why higher bleeding rates are seen in women, Dr. Mehran said though her team did not study “cause and effect,” it is possible that “whatever differences were seen are most likely related to the comorbidities.

“When you look at the interaction between the sexes you see that disruption is bad for both sexes,” she continued. “Disruptions usually were from a clinical event such as bleeding and women had more bleeding therefore they [likely] have more disruptions. That’s what we think, and that’s all that we could say.”

Study Details

Women were less likely to have thrombotic lesions (P = .002) and more likely to have a shorter stent lengths (P = .01).

Note: Dr. Mehran is a faculty member of the Cardiovascular Research Foundation, which owns and operates TCTMD.

 

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Source:
Mehran M. Impact of sex on modes of dual antiplatelet therapy cessation and clinical outcomes following PCI: results from the “patterns of non-adherence to antiplatelet regimens in stented patients” (PARIS) registry. Presented at: EuroPCR; May 21, 2014; Paris, France.

 

 

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