Baseline Stroke Risk and Efficacy of Dual-Antiplatelet Therapy : A Post Hoc Analysis of the POINT Trial

BACKGROUND: High-risk transient ischemic attacks and minor ischemic strokes are followed by a variable risk of ischemic stroke. We aimed to determine how baseline stroke risk modified the efficacy of clopidogrel-aspirin (referred to here as dual-antiplatelet therapy [DAPT]) for transient ischemic attack and minor ischemic stroke.

METHODS: We performed an unplanned secondary analysis of the POINT trial (Platelet-Oriented Inhibition in New Transient Ischemic Attack and Minor Ischemic Stroke). We first evaluated the associations of the CHA2DS2-VASc and stroke prognosis instrument II (SPI-II) scores with the risk of incident ischemic stroke and major hemorrhage (intracranial hemorrhage or major systemic hemorrhage). We then tested for heterogeneity of the relative and absolute treatment effect of DAPT relative to aspirin across low- and high-risk patient subgroups.

RESULTS: A total of 4841 trial participants were included in this analysis, with 2400 participants assigned to treatment with short-term DAPT and 2430 participants to treatment with aspirin and placebo. The dichotomized SPI-II score, but not the CHA2DS2-VASc score (P=0.18), was associated with the risk of incident ischemic stroke. A high-risk SPI-II score (>3) was associated with greater risk of incident ischemic stroke (hazard ratio of incident ischemic stroke relative to low-risk SPI-II score of 1.84 [95% CI, 1.44-2.35]; P<0.001) and numerically greater risk of major hemorrhage though not meeting statistical significance (hazard ratio, 1.80 [95% CI, 0.90-3.57]; P=0.10). The relative risk reduction with DAPT was similar across SPI-II strata (Pinteraction=0.31). The absolute risk reduction for ischemic stroke with DAPT compared with aspirin was nearly 4-fold higher (2.80% versus 0.76%; number needed to treat, 31 versus 131) in the high-risk SPI-II stratum relative to the low-risk stratum. The absolute risk increase for major hemorrhage with DAPT compared with aspirin was 3-fold higher (0.84% versus 0.30%; number needed to harm, 119 versus 331) in the high-risk SPI-II stratum relative to the low-risk stratum.

CONCLUSIONS: Stratification by baseline stroke risk identifies a patient subgroup that derives greater absolute benefit from treatment with DAPT.

REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00991029.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:55

Enthalten in:

Stroke - 55(2024), 2 vom: 09. Feb., Seite 385-391

Sprache:

Englisch

Beteiligte Personen:

Daghlas, Iyas [VerfasserIn]
Johnston, S Claiborne [VerfasserIn]
Easton, J Donald [VerfasserIn]
Kim, Anthony S [VerfasserIn]

Links:

Volltext

Themen:

Aspirin
Ischemic attack, transient
Journal Article
Platelet Aggregation Inhibitors
Platelet aggregation inhibitors
Precision medicine
R16CO5Y76E
Stroke

Anmerkungen:

Date Completed 01.02.2024

Date Revised 11.02.2024

published: Print-Electronic

ClinicalTrials.gov: NCT00991029

Citation Status MEDLINE

doi:

10.1161/STROKEAHA.123.044927

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM366651900