“Simple five-item risk score” could be used to predict bleeding risk associated with dual antiplatelet therapy

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Marco Valgimigli

Francesco Costa (Swiss Cardiovascular Center Bern, Bern University Hospital, Bern, Switzerland) and others report in The Lancet that the PRECISE-DAPT score—“a simple five-item risk score”—could be used to predict the risk of out-of-hospital bleeding in patients receiving dual antiplatelet therapy (DAPT) after undergoing percutaneous coronary intervention (PCI). Therefore, the score could be used to determine which patients may be at potential harm from prolonged duration of DAPT.

The authors report that the optimal duration of DAPT after PCI is still debated because while prolonging treatment beyond 12 months is associated with ischaemic benefits, it is also associated with increased bleeding. They add that although international guidelines advise prescribing DAPT for fewer than 12 months in patients at high risk of bleeding, “no standardised tool exists to weigh bleeding risk at time of DAPT initiation”. Therefore—using a large pooled dataset of contemporary randomised clinical trials implementing different DAPT strategies—Costa et al created a bleeding risk score.

In the PRECISE-DAPT collaborative study, 14,963 patients underwent elective, urgent, or emergent PCI with a coronary stent and were prescribed DAPT—typically comprising of aspirin and clopidogrel—afterwards. The primary endpoint of the analysis was out-of-hospital bleeding; defined according to the thrombolysis in myocardial infarction (TIMI) definition. Overall, this endpoint occurred in 218 patients (12.5 per 1,000 patients at year one), and 124 of these patients had a major bleeding event. “From the final multivariate model, we developed a five-item bleeding risk score (age, creatinine clearance, haemoglobin, white-blood-cell count at baseline, and previous spontaneous bleeding—the PRECISE-DAPT score) assigning points to each predictor with bleeding,” Costa et al report. They add that score discrimination “was consistent regardless of the clinical presentation at the time of PCI or treatment with clopidogrel or ticagrelor but was apparently lower for patients treated with prasugrel and higher for those treated with proton-pump inhibitors”.

Furthermore, the authors report that prolonged DAPT in patients who were at high risk of bleeding, according to the score, was associated with a “remarkable bleeding burden, leading to a number needed to treat for harm of 38” but was not associated with an ischaemic benefit. By contrast, they note, prolonged DAPT in patients without a high risk of bleeding was associated with “marginal or even no increase of bleeding and a significant reduction of the composite endpoint ischaemic endpoint”.

They comment: “Selecting upfront a shorter than 12-month treatment duration [of DAPT] in patients deemed at high bleeding risk (PRESCISE-DAPT score ≥25) might prevent exposing them to an excessive bleeding hazard. In turn, patients at non-high bleeding risk (PRECISE-DAPT score <25) might receive a standard (ie. 12 months) or a prolonged (ie >12 months) course of treatment if tolerated.”

Additionally, in a separate analysis, the PRECISE-DAPT was able to determine which patients with acute coronary syndrome had excessive bleeding risk and did not derive ischaemic benefit from receiving DAPT for 12 months or 24 months—at present, 12 months of DAPT is recommended for patients who have undergone PCI for acute coronary syndrome.

Costa et al conclude: “The PRECISE-DAPT score identified patients in whom the benefits of prolonged DAPT outweighed the risks and vice versa. In the context of a comprehensive clinical evaluation, this tool can support clinical decision making for treatment duration. Prospective validation of this score in practice remains desirable.”

Responding to our question about the relevance of the stent used (ie. first-generation vs. second-generation drug-eluting stent) to the score, study author Marco Valgimigli (Swiss Cardiovascular Center Bern, Bern University Hospital, Bern, Switzerland) told Cardiovascular News: “PRECISE DAPT is a pure bleeding risk score. Since bleeding risk is not affected by type of stent implanted, PRECISE DAPT does not take that into account.

“Despite being a pure bleeding risk score, we have produced evidence that bleeding risk trumps ischaemic risk—ie. irrespective of the ischaemic risk, if your bleeding risk is high (PRECISE DAPT ≥25), then you are better off receiving a shorter rather than longer DAPT duration.”

He adds: “It is, however, fair to state that the proportion of first generation drug-eluting stents in the database used to generate the score was relatively limited. We did not see any signal that the score may work differently in first or second generation drug-eluting stents but I would caution towards the possibility that in a larger dataset of patients with first-generation drug-eluting stents, the outcomes may be different. That said, first-generation drug-eluting stents no longer exist and we do have a score (i.e. DAPT score) that takes that element into account.  So, I think this is not a real limitation of PRECISE DAPT, which has been developed to provide answers to contemporary population undergoing stenting. With this respect, it is actually an advantage that we are not taking stent type into account as, again, first generation drug-eluting stentsare no longer in use.”