Prevalence of Undiagnosed Atrial Fibrillation and of That Not Being Treated With Anticoagulant Drugs: the AFABE Study

Introduction and objectivesAtrial fibrillation constitutes a serious public health problem because it can lead to complications. Thus, the management of this arrhythmia must include not only its treatment, but antithrombotic therapy as well. The main goal is to determine the proportion of cases of undiagnosed atrial fibrillation and the proportion of patients not being treated with oral anticoagulants.MethodsA multicenter, population-based, retrospective, cross-sectional, observational study. In all, 1043 participants over 60 years of age were randomly selected to undergo an electrocardiogram in a prearranged appointment. Demographic data, CHA2DS2-VASc and HAS-BLED scores, international normalized ratio results, and reasons for not receiving oral anticoagulant therapy were recorded.ResultsThe overall prevalence of atrial fibrillation was 10.9% (95% confidence interval, 9.1%-12.8%), 20.1% of which had not been diagnosed previously. In the group with known atrial fibrillation, 23.5% of those with CHA2DS2-VASc≥2 were not receiving oral anticoagulant therapy, and 47.9% had a HAS-BLED score≥3. The odds ratio for not being treated with oral anticoagulation was 2.04 (95% confidence interval, 1.11-3.77) for women, 1.10 (95% confidence interval, 1.05-1.15) for more advanced age at diagnosis, and 8.61 (95% confidence interval 2.38-31.0) for a CHA2DS2-VASc score<2. Cognitive impairment (15.2%) was the main reason for not receiving oral anticoagulant therapy.ConclusionsThe prevalence of previously undiagnosed atrial fibrillation in individuals over 60 years of age is 20.1%, and 23.5% of those who have been diagnosed receive no treatment with oral anticoagulants.

ResumenIntroducción y objetivosLa fibrilación auricular significa un grave problema de salud pública por sus complicaciones, por lo que su manejo debería incluir no sólo su tratamiento, sino también la prevención de las complicaciones tromboembólicas. El objetivo principal es conocer las proporciones de la fibrilación auricular desconocida y la no tratada con anticoagulantes.MétodosEstudio observacional, transversal, retrospectivo, de base poblacional y multicéntrico. Se seleccionó aleatoriamente a 1.043 sujetos mayores de 60 años para realizarles un electrocardiograma en visita concertada. Se registraron variables sociodemográficas, valores en las escalas CHA2DS2-VASc y HAS-BLED, razón internacional normalizada y motivos de no recibir tratamiento anticoagulante oral.ResultadosLa prevalencia total de fibrilación auricular fue del 10,9% (intervalo de confianza del 95%, 9,1-12,8%), de la que el 20,1% era desconocida. De la fibrilación auricular conocida, el 23,5% con un valor de CHA2DS2-VASc ≥ 2 no recibía tratamiento anticoagulante y el 47,9% tenía un valor HAS-BLED ≥ 3. La odds ratio de no recibir tratamiento anticoagulante fue 2,04 (intervalo de confianza del 95%, 1,11-3,77) para las mujeres, 1,10 (intervalo de confianza del 95%, 1,05-1,15) para la mayor edad de diagnóstico y 8,61 (intervalo de confianza del 95%, 2,38-31,0) si el valor de CHA2DS2-VASc es < 2. El deterioro cognitivo (15,2%) fue el motivo principal de no recibir tratamiento anticoagulante.ConclusionesEl 20,1% de las fibrilaciones auriculares de pacientes mayores de 60 años son desconocidas previamente y no se trata con anticoagulantes al 23,5% del total.