Risk and Prediction of Sudden Cardiac Death and Ventricular Arrhythmias for Patients with Atrial Fibrillation - A Nationwide Cohort Study

Sudden cardiac death (SCD) is the most devastating manifestation of ventricular arrhythmias (VAs), and is the leading cause of mortality among atrial fibrillation (AF) patients. The goal of the present study was to investigate the incidence of SCD/VAs amongst patients with and without AF. We also aimed to identify important risk factors of SCD/VAs among AF patients. Using the "National Health Insurance Research Database" in Taiwan, a total of 352,656 AF and 352,656 non-AF patients without antecedent SCD/VAs were identified. The annual risk of SCD/VAs was higher in AF than non-AF groups (0.97% versus 0.47%) with an adjusted hazard ratio (HR) of 1.64. The increased risk of SCD/VAs in AF patients was consistently observed in different age strata, various comorbidities and patients without use of class I/III anti-arrhythmic drugs or digoxin. Among AF patients, age >= 75 years, congestive heart failure, hypertension, diabetes mellitus, previous stroke/transient ischemic attack, vascular diseases, chronic kidney disease and chronic obstructive pulmonary disease were important risk factors for SCD/VAs. In conclusion, the risk of SCD/VAs amongst AF patients was 1.64-fold higher compared to non-AF patients, which was associated with the number of clinical risk factors associated with the particular AF patient.