Abstract 17155: Proarrhythmia Associated With Sotalol: Population-Level Incidence and Risk Factors
Introduction: Sotalol's proarrhythmia (PA) effect limits its use, despite its ability to maintain sinus rhythm in atrial fibrillation (AF). Our study reports the first population-based incidence and potential predictors of sotalol-associated PA in a real-world setting.
Methods: We conducted a retrospective cohort study using linked administrative databases containing hospital discharge abstracts, prescription claims and vital status from Quebec, Canada between 1999–2007. All patients 65+ years who were discharged alive with primary or secondary diagnoses of AF were included. Patients with a diagnosis of AF or PA within the prior year were excluded. Patients were identified as being “users” or “non-users” of sotalol based on prescriptions dispensed within 7 days post-AF discharge. PA was defined with ICD-9/10 codes for ventricular tachycardia/fibrillation/flutter, cardiac arrest and sudden death. Potential risk factors for PA and a composite of PA/death were explored using multivariable Cox regression.
Results: There were 2,627 sotalol users in the cohort out of 10,133 AF patients who were prescribed antiarrhythmics and met the inclusion/exclusion criteria. Sotalol users were 75.6+/−6.4 years old, 44.2% male, with 57.5% having hypertension, 29.9% coronary artery disease, but only 5.9% having chronic kidney disease and 11.0% heart failure. A sotalol daily dose of ≤160mg was used in 91.6% of patients. The crude incidence of PA was 72/2,627 (2.7%) in sotalol users over a median follow-up of 2.1 years. The crude incidence of PA in male and female users was 6.1 and 6.7/1000 person-years, respectively. Crude incidence rose to 8.7 and 13.1/1000 person-years, respectively, in patients with a baseline history of heart failure and chronic kidney disease. No significant predictors of PA or PA/death in sotalol users were found, although trends were found for age, kidney disease, and diabetes.
Conclusions: Population-based incidence of PA in sotalol users is in the lower range of what has been previously reported. Clinicians appear to prescribe sotalol in the real-world setting at low-moderate doses, mainly avoiding patients with known risk factors for PA, resulting in a lower than expected number of PA events.
- © 2010 by American Heart Association, Inc.