Fish intake and risk of incident atrial fibrillation

Abstract

Background: Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and is particularly common in the elderly. Although effects of fish intake, including potential antiarrhythmic effects, may favorably influence risk of AF, relationships between fish intake and AF incidence have not been evaluated.

Methods and results: In a prospective, population-based cohort of 4815 adults > or =age 65 years, usual dietary intake was assessed at baseline in 1989 and 1990. Consumption of tuna and other broiled or baked fish correlated with plasma phospholipid long-chain n-3 fatty acids, whereas consumption of fried fish or fish sandwiches (fish burgers) did not. AF incidence was prospectively ascertained on the basis of hospital discharge records and annual electrocardiograms. During 12 years' follow-up, 980 cases of incident AF were diagnosed. In multivariate analyses, consumption of tuna or other broiled or baked fish was inversely associated with incidence of AF, with 28% lower risk with intake 1 to 4 times per week (HR=0.72, 95% CI=0.58 to 0.91, P=0.005), and 31% lower risk with intake > or =5 times per week (HR=0.69, 95% CI=0.52 to 0.91, P=0.008), compared with <1 time per month (P trend=0.004). Results were not materially different after adjustment for preceding myocardial infarction or congestive heart failure. In similar analyses, fried fish/fish sandwich consumption was not associated with lower risk of AF.

Conclusions: Among elderly adults, consumption of tuna or other broiled or baked fish, but not fried fish or fish sandwiches, is associated with lower incidence of AF. Fish intake may influence risk of this common cardiac arrhythmia.

Figure 1

AF-free survival according to fish consumption.

Figure 2

AF incidence according to both tuna/other fish and fried fish/fish sandwich consumption. For groups consuming tuna/other fish ≥1/week, AF cases/numbers at risk were 161/781, 213/1031, and 234/1362 for fried fish/fish sandwich intake ≥1/week, 1–3/month, and <1/month, respectively; for groups consuming tuna/other fish 1–3/month, the corresponding numbers were 29/99, 78/416, and 134/613; and for groups consuming tuna/other fish <1/month, the corresponding numbers were 20/60, 32/119, and 79/334.