26. EFFECT OF RISK STATUS & TREATMENT ON THE ANNUAL RISK OF STROKE IN NON-RHEUMATIC AF Warfarin Aspirin Untreated Risk group Very high 5% 10% 12% Previous stroke or transient ischaemic attack High 2.5% 5% 6.5% Age > 65 and one other risk factor Moderate Age > 65, no other risk factors 1.5% 3% 4% Age < 65, other risk factors Low 0.5% 1% 1.2% Age < 65 and no other risk factors