Risk of ischaemic stroke in thyrotoxic atrial fibrillation

Abstract

Objective: Atrial fibrillation (AF) is the most common cardiac complication of thyrotoxicosis and is strongly implicated in thromboembolic events. However, the incidence of stroke in thyrotoxic AF remains unclear. Herein, we aimed to investigate the risks of mortality and ischaemic stroke between patients with thyrotoxic AF and nonthyrotoxic AF. Designs and Methods: From Taiwan's National Health Insurance Research Database, 1868 patients with the concomitant diagnoses of AF and thyrotoxicosis identified between 2001 and 2010 were compared to 7472 patients with nonthyrotoxic AF using propensity score matching for age, sex and comorbidities. Results: There was no significant difference in either CHA2DS2-VASc score or anticoagulant usage between the groups. Alternatively, the thyrotoxic group contained more β-blocker/digoxin users, whereas the nonthyrotoxic group contained more statin users. Patients with thyrotoxic AF exhibited lower risks of all-cause mortality (HR: 0.66, CI: 0.59-0.73, P