Background and Purpose—In ACTIVE-W, oral anticoagulation (OAC) was more efficacious than combined clopidogrel plus aspirin (CA) in preventing vascular events in patients with atrial fibrillation. However, because OAC carries important bleeding complications, risk stratification schemes have been devised to identify patients for whom the absolute benefits of OAC exceed its risks. Methods—Participants were risk-stratified with the widely-used CHADS2 scheme. Treatment-specific rates of stroke and major bleeding were calculated for patients with a CHADS21 and compared to those with a CHADS21. Results—Observed stroke rates for those with a CHADS21 were 1.25% per year on CA and 0.43% per year on OAC (RR2.96, 95% CI: 1.26 to 6.98, P0.01). Among patients with a CHADS21, the stroke rates were 3.15% per year on CA and 2.01% per year on OAC (RR1.58, 95% CI: 1.11 to 2.24, P0.01) (P for interaction between stroke risk category and efficacy of OAC0.19). The risk of major bleeding during OAC was significantly lower among patients with CHADS21 (1.36% per year) compared with CHADS21 (2.75% per year) (RR0.49, 95% CI 0.30 to 0.79, P0.003). Conclusions—In this clinical trial, patients with a CHADS21 had a low risk of stroke, yet still derived a modest (1% per year) but statistically significant absolute reduction in stroke with OAC and had low rates of major hemorrhage on OAC.
Risks and Benefits of Oral Anticoagulation Compared With Clopidogrel Plus Aspirin in Patients With Atrial Fibrillation According to Stroke Risk. The Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE-W)
DE CATERINA, Raffaele;
2008-01-01
Abstract
Background and Purpose—In ACTIVE-W, oral anticoagulation (OAC) was more efficacious than combined clopidogrel plus aspirin (CA) in preventing vascular events in patients with atrial fibrillation. However, because OAC carries important bleeding complications, risk stratification schemes have been devised to identify patients for whom the absolute benefits of OAC exceed its risks. Methods—Participants were risk-stratified with the widely-used CHADS2 scheme. Treatment-specific rates of stroke and major bleeding were calculated for patients with a CHADS21 and compared to those with a CHADS21. Results—Observed stroke rates for those with a CHADS21 were 1.25% per year on CA and 0.43% per year on OAC (RR2.96, 95% CI: 1.26 to 6.98, P0.01). Among patients with a CHADS21, the stroke rates were 3.15% per year on CA and 2.01% per year on OAC (RR1.58, 95% CI: 1.11 to 2.24, P0.01) (P for interaction between stroke risk category and efficacy of OAC0.19). The risk of major bleeding during OAC was significantly lower among patients with CHADS21 (1.36% per year) compared with CHADS21 (2.75% per year) (RR0.49, 95% CI 0.30 to 0.79, P0.003). Conclusions—In this clinical trial, patients with a CHADS21 had a low risk of stroke, yet still derived a modest (1% per year) but statistically significant absolute reduction in stroke with OAC and had low rates of major hemorrhage on OAC.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
