Limited duration of antiarrhythmic drug use for newly diagnosed atrial fibrillation in a nationwide population under age 65

J Cardiovasc Electrophysiol. 2021 Jun;32(6):1529-1537. doi: 10.1111/jce.15012. Epub 2021 Apr 3.

Abstract

Introduction: Antiarrhythmic drugs (AADs) are commonly used for the treatment of newly diagnosed symptomatic atrial fibrillation (AF), however initial AAD choice, duration of therapy, rates of discontinuation, and factors associated with a durable response to therapy are poorly understood. This study assesses the initial choice and duration of antiarrhythmic drug therapy in the first 2 years after diagnosis of AF in a younger, commercially insured population.

Methods: A large nationally representative sample of patients age 20-64 was studied using the IBM MarketScan Database. Patients who started an AAD within 90 days of AF diagnosis with continuous enrollment for 1-year pre-index diagnosis and 2 years post-index were included. A Cox proportional hazards model was used to determine factors associated with AAD discontinuation.

Results: Flecainide was used most frequently (26.8%), followed by amiodarone (22.5%), dronedarone (18.3%), sotalol (15.8%), and propafenone (14.0%), with other AADs used less frequently. Twenty-two percent of patients who started on an AAD underwent ablation within 2 years, with 79% discontinuing the AAD after ablation. Ablation was the strongest predictor of AAD discontinuation (hazard ratio [HR], 1.70; 95% confidence interval [CI]: 1.61-1.80), followed by the male gender (HR, 1.10; CI: 1.02-1.19). Older patients (HR, 0.76; CI: 0.72-0.80; reference age 18-49) and those with comorbidities, including cardiomyopathy (HR, 075; CI: 0.61-0.91), diabetes (HR, 0.83; CI: 0.75-0.91), and hypertension (HR, 0.87; CI: 0.81-0.94) were less likely to discontinue AADs.

Conclusion: Only 31% of patients remained on the initial AAD at 2 years, with a mean duration of initial therapy 7.6 months before discontinuation.

Keywords: antiarrhythmic drugs; atrial fibrillation; catheter ablation.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Amiodarone*
  • Anti-Arrhythmia Agents / adverse effects
  • Atrial Fibrillation* / diagnosis
  • Atrial Fibrillation* / drug therapy
  • Atrial Fibrillation* / epidemiology
  • Catheter Ablation*
  • Flecainide / adverse effects
  • Humans
  • Male
  • Middle Aged
  • Sotalol
  • Treatment Outcome
  • Young Adult

Substances

  • Anti-Arrhythmia Agents
  • Sotalol
  • Flecainide
  • Amiodarone