Effect of fish oil on ventricular tachyarrhythmia and death in patients with implantable cardioverter defibrillators: the Study on Omega-3 Fatty Acids and Ventricular Arrhythmia (SOFA) randomized trial

JAMA. 2006 Jun 14;295(22):2613-9. doi: 10.1001/jama.295.22.2613.


Context: Very-long-chain n-3 polyunsaturated fatty acids (omega-3 PUFAs) from fish are thought to reduce risk of sudden death, possibly by reducing susceptibility to cardiac arrhythmia.

Objective: To study the effect of supplemental fish oil vs placebo on ventricular tachyarrhythmia or death.

Design, setting, and patients: The Study on Omega-3 Fatty acids and ventricular Arrhythmia (SOFA) was a randomized, parallel, placebo-controlled, double-blind trial conducted at 26 cardiology clinics across Europe. A total of 546 patients with implantable cardioverter-defibrillators (ICDs) and prior documented malignant ventricular tachycardia (VT) or ventricular fibrillation (VF) were enrolled between October 2001 and August 2004. Patients were randomly assigned to receive 2 g/d of fish oil (n = 273) or placebo (n = 273) for a median period of 356 days (range, 14-379 days).

Main outcome measure: Appropriate ICD intervention for VT or VF, or all-cause death.

Results: The primary end point occurred in 81 (30%) patients taking fish oil vs 90 (33%) patients taking placebo (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.64-1.16; P = .33). In prespecified subgroup analyses, the HR was 0.91 (95% CI, 0.66-1.26) for fish oil vs placebo in the 411 patients who had experienced VT in the year before the study, and 0.76 (95% CI, 0.52-1.11) for 332 patients with prior myocardial infarctions.

Conclusion: Our findings do not indicate evidence of a strong protective effect of intake of omega-3 PUFAs from fish oil against ventricular arrhythmia in patients with ICDs.

Trial registration: clinicaltrials.gov Identifier: NCT00110838.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cause of Death
  • Defibrillators, Implantable*
  • Dietary Supplements
  • Double-Blind Method
  • Fatty Acids, Omega-3 / administration & dosage*
  • Female
  • Heart Diseases / mortality
  • Heart Diseases / therapy*
  • Humans
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Tachycardia, Ventricular / epidemiology*


  • Fatty Acids, Omega-3

Associated data

  • ClinicalTrials.gov/NCT00110838