Familial Aggregation of Lone Atrial Fibrillation in Young Persons

Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
Journal of the American College of Cardiology (Impact Factor: 16.5). 06/2012; 60(10):917-21. DOI: 10.1016/j.jacc.2012.03.046
Source: PubMed


This study investigated whether an individual's risk of developing lone atrial fibrillation (AF) before age 60 years is associated with lone AF in relatives.
Genetic factors may play a role in the development of lone AF.
Using Danish national registers, a cohort was established of ~4 million persons born between 1950 and 2008, and those with a family history of lone AF (AF without preceding cardiovascular/endocrine diagnoses) were identified. Individuals were followed up until the first diagnosis of lone AF. Poisson regression was used to estimate incidence rate ratios (IRRs).
In ~92 million person-years of follow-up, 9,507 persons were identified as having lone AF. The IRRs for lone AF given an affected first- or second-degree relative were 3.48 (95% confidence interval [CI]: 3.08 to 3.93) and 1.64 (95% CI: 1.04 to 2.59), respectively. IRRs were higher for men than for women but were not associated with the affected relative's sex. IRR for lone AF was 6.24 (95% CI: 2.59 to 15.0), given at least 2 first-degree relatives affected with lone AF. The IRR for lone AF in persons aged <40 years given a first-degree relative affected at age <40 years was 5.42 (95% CI: 3.80 to 7.72), and 8.53 (95% CI: 3.82 to 19.0) in persons age <30 years given a first-degree relative affected at age <30 years.
A family history of lone AF is associated with substantial risk of lone AF, with the strongest risks associated with young age at onset, multiple affected relatives, and in first-degree relatives. These results suggest routine evaluation of the families of at least certain types of patients with lone AF.

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Available from: Mattis Flyvholm Ranthe, Feb 17, 2015
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