What you don't know can kill you

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide, afflicting an estimated 33 million people.1 In the United States alone, AFrelated annual cost estimates are as high as $26 billion. While some patients experience bothersome symptoms, many remain completely asymptomatic. Most concerning is the severe consequence of untreated AF. Patients with AF are at an increased risk of stroke and systemic embolism, up to 15% per year.2 In the United States, 800 000 people suffer a stroke annually, and these strokes cause one in every 20 deaths.1 This converts to one stroke every 40 seconds and one strokerelated death every 4 minutes. Despite these staggering statistics, there has long been anecdotal evidence that most of the atrisk population is unaware of AF or its association with stroke risk. In fact, prior studies have suggested that public screening of adults ages 65 and older would identify one new diagnosis of AF for every 170 adults screened.1 Additionally, inadequate understanding of how AF can cause stroke may contribute to the underutilization of, poor adherence to, and frequent early discontinuation of stroke preventative medications (eg, anticoagulants) among AF patients.3 To better understand the global awareness of AF, Wendelboe and colleagues conducted a global survey to quantify public awareness of AF in comparison to other thrombotic and nonthrombotic illnesses.4 Unsurprisingly, they found less than half (48%) of those surveyed were aware of AF. This differed considerably from the high awareness of heart attacks (74%), stroke (81%), human immunodeficiency/acquired immunodeficiency syndrome (HIV/AIDS; 80%), breast cancer (81%), and prostate cancer (78%). Additionally, they found a striking difference in awareness by country, with Uganda reporting the highest awareness (69%) and Canada the lowest (25%). While differences in the surveyed population and potential selection/responder bias may have contributed to part of the variation, a nearly threefold difference is hard to ignore. Perhaps the most important finding from this report is that only 36% of respondents were aware that AF can lead to stroke. With such prominent morbidity and mortality associated with stroke and the presence of a highly effective prevention method (anticoagulation), one would hope that the awareness of this connection was higher. To help contextualize, the World Health Organization estimates 2.1 million global cases of HIV with one million yearly deaths.5 They also estimate annual deaths due to breast cancer around 500 000 globally while the World Cancer Research Fund estimates 1.1 million global cases of prostate cancer annually. Each are incredibly important diseases worthy of robust public awareness campaigns. So too is AF, for which millions of people worldwide are at high risk of a potentially devastating stroke. Nonetheless, awareness of these conditions was strikingly higher than AF in this survey. The role that advocacy organizations play in public awareness should not be underestimated. In fact, the World Health Organization has identified nine global public health days to raise awareness of HIV/AIDS, tobacco use, tuberculosis, and malaria. However, they do not have a day associated with AF, despite its sizeable prevalence and potentially devastating morbidity and mortality. Other wellfunded and wellorganized movements focused solely on HIV/AIDS and specific cancer types (eg, breast and prostate). It is no wonder that these conditions have gained widespread awareness across the globe. For the cardiovascular conditions, many major organizations (eg,the American Heart Association/American Stroke Association and the European Society of Cardiology) have focused on risk factor and lifestyle modification in their public health awareness campaigns. Additionally, these major cardiovascular organizations cover a wide range of diseases, from coronary artery disease and stroke to sudden cardiac death and atrial fibrillation. This diversity may limit the awareness of any specific disease, such as atrial fibrillation. To help address a public knowledge gap regarding thrombosis, the International Society on Thrombosis and Haemostasis began World Thrombosis Day in 2014.6 This effort, in partnership with a number of other thrombosisrelated organizations, focuses on public awareness of thrombotic disorders, primarily venous thromboembolism and AF.