BACKGROUND:N-3 fatty acids may reduce the risk of sudden death by preventing life-threatening cardiac arrhythmias. Heart rate variability (HRV) and baroreflex sensitivity (BRS) reflect cardiac autonomic regulation; reduced values predict arrhythmic events and mortality. Effects of n-3 fatty acids on these risk indicators of arrhythmia have not been widely studied. We investigated the effect of supplemental intake of n-3 fatty acids on HRV and BRS in apparently healthy subjects aged 50 to 70 years. METHODS: After a run-in period of 4 weeks, 84 subjects were randomized to receive capsules with either 3.5 g of fish oil or placebo oil daily for 12 weeks. Before and after intervention, electrocardiograms and blood pressure were recorded for 10 minutes with standardized respiration of 15 breaths/min. The SD of the duration of all normal RR intervals (SDNN10) and the root mean square successive differences (RMSSD10) were calculated from the 10-minute recordings. We also computed low frequency power (LF) and high frequency power (HF). BRS was computed by integrating the spectral systolic blood pressure to interbeat-interval transfer function in the 0.05- to 0.15-Hz band. RESULTS: The different measures of HRV and BRS did not significantly improve with the intake of n-3 fatty acids. SDNN10 decreased by 3.05 ms or 7.7% (95% CI, -8.91-2.82 ms), and BRS decreased by 0.92 ms/mm Hg or 0.1% (95% CI, -2.66-0.81 ms/mm Hg) in the fish oil group compared with the placebo group. CONCLUSIONS:N-3 fatty acids have no effect on HRV from short-term recordings and BRS in apparently healthy subjects.
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BACKGROUND:N-3 fatty acids may reduce the risk of sudden death by preventing life-threatening cardiac arrhythmias. Heart rate variability (HRV) and baroreflex sensitivity (BRS) reflect cardiac autonomic regulation; reduced values predict arrhythmic events and mortality. Effects of n-3 fatty acids on these risk indicators of arrhythmia have not been widely studied. We investigated the effect of supplemental intake of n-3 fatty acids on HRV and BRS in apparently healthy subjects aged 50 to 70 years. METHODS: After a run-in period of 4 weeks, 84 subjects were randomized to receive capsules with either 3.5 g of fish oil or placebo oil daily for 12 weeks. Before and after intervention, electrocardiograms and blood pressure were recorded for 10 minutes with standardized respiration of 15 breaths/min. The SD of the duration of all normal RR intervals (SDNN10) and the root mean square successive differences (RMSSD10) were calculated from the 10-minute recordings. We also computed low frequency power (LF) and high frequency power (HF). BRS was computed by integrating the spectral systolic blood pressure to interbeat-interval transfer function in the 0.05- to 0.15-Hz band. RESULTS: The different measures of HRV and BRS did not significantly improve with the intake of n-3 fatty acids. SDNN10 decreased by 3.05 ms or 7.7% (95% CI, -8.91-2.82 ms), and BRS decreased by 0.92 ms/mm Hg or 0.1% (95% CI, -2.66-0.81 ms/mm Hg) in the fish oil group compared with the placebo group. CONCLUSIONS:N-3 fatty acids have no effect on HRV from short-term recordings and BRS in apparently healthy subjects.
Authors: Katherine A Sauder; Ann C Skulas-Ray; Tavis S Campbell; Jillian A Johnson; Penny M Kris-Etherton; Sheila G West Journal: Psychosom Med Date: 2013-04-16 Impact factor: 4.312
Authors: George E Billman; Yoshinori Nishijima; Andriy E Belevych; Dmitry Terentyev; Ying Xu; Kaylan M Haizlip; Michelle M Monasky; Nitisha Hiranandani; William S Harris; Sandor Gyorke; Cynthia A Carnes; Paul M L Janssen Journal: Am J Physiol Heart Circ Physiol Date: 2010-01-22 Impact factor: 4.733