Abstract 3700: Impact of Vascular Events on Mortality in AF Patients: Insights from ACTIVE W
Background and Methods: Guidelines and clinical decision-making regarding antithrombotic therapy in atrial fibrillation (AF) have focused primarily on stroke prevention. However AF patients on antithrombotic therapy are at risk of multiple different vascular events and of hemorrhage. Strokes differ in severity from non-disabling to very severe. To better understand the clinical importance of different types vascular events and of hemorrhage, we have examined the subsequent risk of death after the occurrence of different types of non-fatal events occurring during ACTIVE W. ACTIVE-W was a randomized trial comparing oral anticoagulation (OAC) with clopidogrel + aspirin (C+A) for prevention of vascular events in high-risk patients with AF which reported that OAC reduced the risk total vascular events (RR 1.45, p<0.001) compared to C+A, but not mortality (RR 1.01 p=0.91).
Results: Out of a total of 3371 randomized to OAC and 3335 patients randomized to C + A, after a median follow up duration of 1.28 years, there were 58 and 100 strokes and there were 158 and 159 deaths, respectively. 59 strokes (37%) were classified as non-disabling (modified Rankin 1–2). Hazard ratios (HR) and 95% confidence intervals for subsequent death associated with the occurrence of different non-fatal vascular events are shown. Major hemorrhage significantly increased the risk of death 2.7 fold. Stroke increased the risk 5.6 fold. Strokes which were either hemorrhagic or disabling (modified Rankin 3– 6) markedly increased the risk of dying, but non-disabling stroke) did not significantly increase the risk of death (HR = 1.38, p=0.52). HR 95% CI P Major bleeding 2.69 1.77 4.08 p<.0001 Severe bleeding 3.56 2.13 5.28 p<.0001 Stroke 5.60 3.85 8.13 p<.0001 Ischemic stroke 5.30 3.54 7.95 p<.0001 Hemorrhagic stroke 7.43 2.76 7.95 p<.0001 Transient ischemic attack 1.06 0.44 2.57 p=0.89 Stroke Severity Non-disabling 1.38 0.52 3.71 p=0.52 Disabling 9.56 6.43 14.22 p<.0001 Myocardial infarction 4.75 2.66 8.47 p<.0001 Non-CNS embolism 2.80 0.90 8.78 p=0.08
Conclusion: Major hemorrhage and other vascular events increase the risk of death. But TIA and non-disabling stroke do not. The negative impact of major bleeding is an important factor in evaluation of antithrombotic therapies.