Fish oils show ‘no major’ protection against heart failure
MedWire News: Dutch researchers have thrown doubt on the proposed link between consumption of fish oils and reduced risk for heart failure (HF).
While the study found no overall protective effect of fish or its constituent fatty acids on HF, diabetic patients did, however, show some reduction in HF risk when consuming the highest level of fish oil.
“Our findings do not support a major role for fish intake in the prevention of heart failure,” Johanna Geleijnse (Wageningen University) and colleagues assert in the European Journal of Heart Failure.
Results from observational and experimental studies suggest that consumption of a small amount of fatty fish, or supplementation with its long chain n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), could protect against coronary heart disease (CHD).
So far only one study has examined the relationship between fish intake and the risk for HF – finding a lower incidence of HF with consumption of tuna or other broiled or baked fish, but not fried fish, over 12 years of follow-up.
For the current study Geleijnse and colleagues assessed 5299 individuals, age an average of 69 years (41% men) who were free from HF and enrolled on the population-based Rotterdam Study.
A trained dietician interviewed the participants using an extensive, validated, semi-quantitative food-frequency questionnaire.
During 11.4 years of follow-up, 669 participants developed HF.
Individuals who consumed 20 g of fish per day or more showed no significant reduction in risk for HF relative to those who consumed no fish at all (risk ratio[RR]=0.96).
Individuals whose consumption of EPA plus DHA was in the highest quintile of the population had a decreased risk for HF compared with those in the lowest quintile (RR=0.89), although the result was not significant.
Notably, women but not men who consumed the highest amount of EPA plus DHA had a reduced risk for HF that was approaching significance (RR=0.75); similarly diabetics who consumed the highest EPA/DHA had a reduced risk for HF that was borderline significant (RR=0.58).
In response to the study, British Heart Foundation senior cardiac nurse June Davison reminded patients that fish oils may still be of some benefit to cardiovascular health.
“We already know that eating oily fish such as salmon, mackerel or sardines can help prevent CHD.
“To help protect your heart health you should eat one–two portions of oily fish, each week. If you have had a heart attack you should aim to increase this to two or three portions each week.”
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By Andrew Czyzewski