Voorspellers mortaliteit in ACTIVE-W trial geïdentificeerdNieuws - Aug. 17, 2010
Een nieuwe analyse van de ACTIVE-W trial laat zien dat invaliderende beroertes en ernstige bloedingen beiden geassocieerd zijn met een verhoogd risico op mortaliteit bij patiënten met atrium fibrilleren (AF) die antitrombotische therapie krijgen.
De onderzoekers vinden dan ook dat toekomstig onderzoek zich meer moet focussen op de preventie van betreffende events en minder de nadruk moet leggen op niet-invaliderende beroertes en niet-ernstige bloedingen, welke beiden de mortaliteit niet verhoogden in deze analyse.
The Atrial Fibrillation Clopidogrel Trial with Irbesartan for Prevention of Vascular Events (ACTIVE-W) was the largest trial conducted to date into the relative efficacy and safety of different antithrombotic therapies. It revealed a 37% reduction in strokes associated with dose-adjusted warfarin but no significant mortality benefit of warfarin over aspirin.
In this analysis, Raffaele De Caterina (Institute of Cardiology, G d'Annunzio University, Chieti, Italy) and colleagues assessed the risk for death after the occurrence of different types of nonfatal events among participants in the ACTIVE-W trial.
"Antithrombotic therapies in AF have primarily focused on stroke prevention and bleeding. However, strokes and bleeds differ in severity, and the level of severity may differently impact mortality," De Caterina and team explain.
The median follow-up time in the study was 1.28 years and the analysis included 3371 warfarin-treated patients and 3335 clopidogrel/aspirin-treated patients.
Writing in the European Heart Journal, the authors reveal that the hazard ratios for mortality associated with various nonfatal events were as follows: 5.8 for nonfatal stroke; 5.29 for nonfatal ischemic stroke; 7.38 for nonfatal hemorrhagic stroke; 9.54 for disabling stroke (modified Rankin Score ≥3); and 3.35 for severe bleeding.
By contrast, transient ischemic attack, non-disabling stroke, and major non-severe bleeding did not increase mortality.
In an editorial accompanying the report, Deirdre Lane and Gregory Lip, both from the University of Birmingham, UK, warn against the overinterpretation of the findings given that it is a secondary analysis and based on a small number of events.
"Although mortality is a key outcome, and the prevention of death is important, the emphasis for antithrombotic therapy in patients with AF should remain on the prevention of stroke, particularly disabling strokes and their sequelae," the commentators say.
They add: "Individual assessment of the net clinical benefit of antithrombotic treatment for the patient based on stroke and bleeding risk stratification is essential."