Study: New-Onset Atrial Fibrillation Increases Cancer Risk

A new analysis finds a connection between new-onset atrial fibrillation (AF) and an elevated cancer risk beyond 1 year of AF diagnosis in a large, initially healthy female cohort.

A group including researchers from Brigham and Women’s Hospital, Boston University, and University Hospital of Basel in Switzerland sought to examine the associations between AF and cancer in a large, long-term, prospective cohort study. The authors evaluated a total of 34,691 women aged 45 years old or older and free of AF, cardiovascular disease, and cancer at baseline. Participants were prospectively followed up between 1993 and 2013 for incident AF and malignant cancer within the Women’s Health Study. Cox proportional hazards models using time-updated covariates were constructed to assess the link between new-onset AF and subsequent cancer, and to adjust for potential confounders, with data analysis being performed from December 2014 to May 2015.
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During the median follow-up period, new-onset AF and malignant cancer were confirmed among 1467 participants. AF was a “significant risk factor” for incident cancer in age-adjusted and multivariable-adjusted models, with the relative risk of cancer being highest in the first 3 months after new-onset AF but remaining considerable beyond 1 year after new-onset AF, according to the authors, who also note observed a trend toward an increased cancer mortality. In contrast, the relative risk of AF among women with new-onset cancer was increased only within the first 3 months.

Primary care physicians must “be aware of the relationship between AF and malignant cancers,” said study coauthor David Conen, MD, MPH, a physician in the Department of Medicine at University Hospital of Basel.

“Our data emphasize the importance of risk factor reduction in AF patients to not only reduce recurrent AF episodes, but to also potentially decrease other adverse outcomes, such as cancer,” Conen said.

“Therefore, AF patients should be closely followed and should receive optimal medical therapy,” he said, adding that future studies “should assess whether incorporating AF into cancer prediction models improve the performance of these scores.”

—Mark McGraw

Reference:

Conen D, Wong JA, Sandhu RK, et al. Risk of malignant cancer among women with new-onset atrial fibrillation [published online May 25, 2016]. JAMA Cardiol. doi:10.1001/jamacardio.2016.0280.