High fish oil intake has no mortality benefit for CAD patients
MedWire News: Fish oil consumption is not associated with reduced coronary risk among patients with stable coronary artery disease (CAD) who already have a relatively high intake, research shows.
"Only subjects with a very low intake of n-3 LCPUFAs appear to have an increased risk of suffering a coronary event," say Elin Strand (University of Bergen, Norway) and colleagues.
"This small proportion of patients may benefit from increasing their fish- or cod liver oil intakes."
The study population, which comprised 2412 participants in the Western Norway B Vitamin Intervention Trial, had a generally high intake of fish and n-3 long-chain polyunsaturated fatty acids (LCPUFAs), with more than 98% consuming amounts above that considered to be protective (0.25-0.50 g/day).
Of the study participants, 84.7% had stable angina pectoris, 14.1% had acute coronary syndromes, and 1.3% had aortic valve stenosis. During 4.8 years of follow-up, 292 patients suffered a coronary event, 76 of whom died of cardiac causes, and 298 had progression of CAD.
The researchers divided the participants into quartiles of n-3 LCPUFA intake, finding average intakes of 0.58, 0.83, 1.36, and 2.64 g/day for quartiles 1, 2, 3, and 4, respectively.
Patients' risk for coronary events did not differ according to which quartile of n-3 LCPUFA as a percentage of total energy intake they were in. Neither did their risk for all-cause death, coronary death, acute myocardial infarction, or progression of CAD differ with n-3 LCPUFA intake.
There were also no associations between fish intake and any of the study endpoints.
The researchers did find evidence for an increased risk for coronary events among patients with an n-3 LCPUFA intake of less than about 0.30 g/day, with the risk nearly doubling at the very lowest levels.
"Only patients with very low intakes of these fatty acids may reduce their risk of coronary events by increasing their intakes," they conclude in the American Journal of Clinical Nutrition.
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By Eleanor McDermid