Prevalence of atrial fibrillation in Spain. OFRECE study results.
OBJECTIVE
Atrial fibrillation is associated with substantial morbidity and mortality and both its incidence and prevalence are high. Nevertheless, comprehensive data on this condition in Spain are lacking. The aim of this study was to estimate the prevalence of atrial fibrillation in Spain.


METHODS
A cross-sectional study was conducted in the general Spanish population older than 40 years. Two-stage random sampling was used, in which first-stage units were primary care physicians randomly selected in every Spanish province and second-stage units were 20 randomly selected persons drawn from each participating physician's assigned population. The reported prevalence was standardized for the age and sex distribution of the Spanish population. The electrocardiogram recordings were read centrally.


RESULTS
Overall, 8343 individuals were evaluated. The mean age was 59.2 years (95% confidence interval, 58.6-59.8 years), and 52.4% of the participants were female. The overall age-adjusted prevalence of atrial fibrillation was 4.4% (95% confidence interval, 3.8-5.1). Prevalence was similar in both sexes, men 4.4% (3.6-5.2) and women 4.5% (3.6-5.3), rising with increasing age older than 60 years. In patients older than 80 years, the prevalence was 17.7% (14.1-21.3). In 10% of patients an unknown atrial fibrillation was diagnosed.


CONCLUSIONS
The prevalence of atrial fibrillation in the general Spanish population older than 40 years is high, at 4.4%. The prevalence is similar in both sexes and rises steeply above 60 years of age. It is estimated that there are over 1 million patients with atrial fibrillation in the Spanish population, of whom over 90,000 are undiagnosed.
Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain. Electronic address: jjgomezdoblas@secardiologia.es.
Juan José
JJ
Gómez-Doblas
Instituto Universitario de Ciencias de la Salud, Universidad de A Coruña, A Coruña, Spain.
Javier
J
Muñiz
Servicio de Cardiología, Hospital Universitario de Fuenlabrada, Fuenlabrada, Madrid, Spain.
Joaquín J Alonso
JJ
Martin
Centro de Salud La Puebla de Montalbán, Toledo, Spain.
Gustavo
G
Rodríguez-Roca
Centro de Salud Jazmín, Madrid, Spain.
José Maria
JM
Lobos
Servicio de Cardiología, Hospital Universitario de Fuenlabrada, Fuenlabrada, Madrid, Spain.
Paula
P
Awamleh
Servicio de Cardiología, Hospital Universitario Vall d'Hebron, Barcelona, Spain.
Gaietá
G
Permanyer-Miralda
Servicio de Cardiología, Hospital Clínico Universitario de Valencia, Valencia, Spain.
Francisco Javier
FJ
Chorro
Servicio de Cardiología, Hospital Reina Sofía, Córdoba, Spain.
Manuel
M
Anguita
Servicio de Cardiología, Hospital de Sant Pau, Barcelona, Spain.
Eulalia
E
Roig
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013030:Spain / Q000453:epidemiology
Atrial fibrillation; Epidemiology; Epidemiología; Fibrilación auricular; Prevalence; Prevalencia