Omega-3 Fatty Acids and Heart Rhythm, Rate, and Variability in Atrial Fibrillation

Abstract

Background Previous randomized control trials showed mixed results concerning the effect of omega-3 fatty acids (n-3 FAs) on atrial fibrillation (AF). The associations of n-3 FA blood levels with heart rhythm in patients with established AF are unknown. The goal of this study was to assess the associations of total and individual n-3 FA blood levels with AF type (paroxysmal versus nonparoxysmal), heart rate (HR), and HR variability in patients with AF. Methods and Results Total n-3 FAs, eicosapentaenoic acid, docosahexaenoic acid, docosapentaenoic acid, and alpha-linolenic acid blood levels were determined in 1969 patients with known AF from the SWISS-AF (Swiss Atrial Fibrillation cohort). Individual and total n-3 FAs were correlated with type of AF, HR, and HR variability using standard logistic and linear regression, adjusted for potential confounders. Only a mild association with nonparoxysmal AF was found with total n-3 FA (odds ratio [OR], 0.97 [95% CI, 0.89-1.05]) and docosahexaenoic acid (OR, 0.93 [95% CI, 0.82-1.06]), whereas other individual n-3 FAs showed no association with nonparoxysmal AF. Higher total n-3 FAs (estimate 0.99 [95% CI, 0.98-1.00]) and higher docosahexaenoic acid (0.99 [95% CI, 0.97-1.00]) tended to be associated with slower HR in multivariate analysis. Docosapentaenoic acid was associated with a lower HR variability triangular index (0.94 [95% CI, 0.89-0.99]). Conclusions We found no strong evidence for an association of n-3 FA blood levels with AF type, but higher total n-3 FA levels and docosahexaenoic acid might correlate with lower HR, and docosapentaenoic acid with a lower HR variability triangular index.

Keywords: atrial fibrillation; heart rate; heart rate variability; omega‐3 fatty acid; rhythm type.

Figure 1. Flow chart of included and excluded patients.

AF indicates atrial fibrillation; HR, heart rate; HRVI, heart rate variability triangular index; n‐3 FA, omega‐3 fatty acid; and SWISS‐AF, Swiss Atrial Fibrillation Cohort.

Figure 2. Summary of main results.

Total n‐3 FAs and DHA were shown to reduce heart rate, and DPA reduced the heart rate variability index. Dashed lines indicate no significant effect between total or individual n‐3 FAs and end points. Symbols of individual n‐3 FAs indicate mainly marine or plant‐derived origin. AF indicates atrial fibrillation; ALA, alpha‐linolenic acid; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid; EPA, eicosapentaenoic acid; and n‐3 FA, omega‐3 fatty acid. Created with BioRender.com.