Abstract 11875: Risk of Malignant Cancer Among Women With New-onset Atrial Fibrillation
Introduction: A substantial proportion of patients with atrial fibrillation (AF) die of non-cardiovascular causes, and recent studies suggest a link between AF and cancer. However, this association has not been evaluated in long-term prospective studies.
Methods: A total of 34691 women ≥45 years and free of AF, cardiovascular disease and cancer at baseline were prospectively followed for incident AF and malignant cancer within the Women’s Health Study. All incident AF and cancer events were validated by medical record review. Cox proportional-hazards models using time-updated covariates were constructed to assess the relationship of new-onset AF with incident cancer and to adjust for potential confounders. We then assessed the risk of incident AF among women with cancer using a similar modelling approach.
Results: Mean age at baseline was 55±7 years. During 19.1 years of follow-up, we observed 1467 (4.2%) AF and 5130 (14.8%) cancer events. AF was a significant risk factor for incident cancer in age-adjusted (hazard ratio (HR) 1.58, 95% confidence interval (CI), 1.34, 1.87, p<0.0001) and multivariable adjusted (HR 1.49, 95% CI, 1.26, 1.77, p<0.0001) models, and was increased among women with paroxysmal (HR 1.35, 95% CI 1.09, 1.67, p=0.005) and non-paroxysmal AF (HR 1.61, 95% CI 1.23, 2.09, p=0.0004). The risk of cancer was highest in the first 3 months after new-onset AF (HR 3.53, 95% CI 2.05, 6.08, p<0.0001) but remained significant beyond 1 year (adjusted HR 1.44, 95% CI 1.19, 1.73, p=0.0001). New-onset AF was also associated with an increased risk of cancer mortality (adjusted HR 1.37, 95% CI 1.01, 1.85, p=0.04). In contrast, women with new-onset cancer had an increased risk of incident AF within 3 months (HR 4.61, 95% CI 2.81, 7.54, p<0.0001) but not beyond 1 year (HR 1.17, 95% CI 0.97, 1.41, p=0.11).
Conclusions: In this large cohort of initially healthy women, new-onset AF was a significant risk factor for the short and long term diagnosis of incident cancer. In contrast, cancer was not associated with an increased AF risk over the long term. Our results may suggest that AF could be an early sign of occult cancer or an underlying systemic process conferring an increased cancer risk.
Author Disclosures: D. Conen: None. J.A. Wong: None. R.K. Sandhu: None. N.R. Cook: None. I. Lee: None. J.E. Buring: None. C.M. Albert: None.
- © 2015 by American Heart Association, Inc.