Stroke as a complication of atrial fibrillation is an important cause of morbidity and mortality worldwide. The incidence of atrial fibrillation is higher in men than in women in all age groups, but, as the linked paper by Friberg and colleagues confirms (doi:10.1136/bmj.e3522),1 women carry a higher risk of stroke than men, a statement that was previously questioned by the National Institute for Health and Clinical Excellence guidelines.2 Nevertheless, there is considerable evidence that women should receive special consideration in relation to preventing stroke in atrial fibrillation.

Until recently the CHADS₂ score was used to classify the risk of stroke in patients with atrial fibrillation. Recently, however, the more detailed CHA₂DS₂-VASc score, which includes female sex as an independent risk factor (counting as 1 point), has been developed.3 The other risk factors included are congestive heart failure, hypertension, diabetes, vascular disease, age 65-74 years, which each count for 1 point, plus age 75 or more …