Incident thromboembolism in the aorta and the renal, mesenteric, pelvic, and extremity arteries after discharge from the hospital with a diagnosis ofatrial fibrillation

Background: The impact of atrial fibrillation (AF) on risk of peripheral ar terial thromboembolism is unknown. Methods: We analyzed the risk of thromboembolism (embolus and/or thrombosis ) in the aorta and the renal, mesenteric, pelvic, and extremity arteries in a cohort of patients discharged from the hospital with an incident diagnos is of AF relative to the risk of thromboembolism in these vessels in the Da nish population. In a random sample of half of the Danish population, 14917 men and 14945 women aged 50 to 89 years were identified in the Danish Nati onal Hospital Discharge Register with a diagnosis of AF from January 1, 198 0, through December 31, 1993. Patients were followed up from diagnosis of A F in the Danish National Hospital Discharge Register and the Causes of Deat h Register until the first diagnosis of a thromboembolic event, death, or t he end of 1993. Risk of a thromboembolic event relative to the risk in the Danish population was analyzed by means of Poisson regression modeling. Results: Patients with a hospital diagnosis of AF had an increased risk of thromboembolic events in the aorta and the renal, mesenteric, pelvic, and e xtremity arteries (relative risk, 4.0 [95% confidence interval, 3.5-4.6] in men; and relative risk, 5.7 [95% confidence interval, 5.1-6.3] in women) c ompared with the Danish population. Conclusion: A hospital diagnosis of AF is an important risk factor for peri pheral arterial thromboembolic complications.