Atrial Fibrillation and Cause‐Specific Risks of Pulmonary Embolism and Ischemic Stroke

BackgroundAtrial fibrillation (AF) is a well‐established risk factor for ischemic stroke (IS). Emerging evidence also indicates an association between AF and pulmonary embolism (PE). Because IS may potentially mediate the observed risk of PE in AF, we aimed to assess the impact of AF on the cause‐specific risks of PE and IS in a large cohort recruited from the general population. Methods and ResultsWe observed 29 842 participants from 3 surveys of the Tromso study (inclusion in 1994–1995, 2001–2002, and 2007–2008) to the end of 2012. Incident events of AF, IS, and PE during follow‐up were recorded, and information on potential confounders was obtained at baseline. Cox regression models, with AF as a time‐dependent variable, were used to calculate cause‐specific hazard ratios (HRs) with 95% confidence intervals (CIs) for PE and IS. There were 2067 participants diagnosed as having AF, 296 with PE and 1164 with IS, during a median of 17.6 years of follow‐up. The risks of PE (HR, 10.88; 95% CI, 6.23–18.89) an...