Positive Health Online

Abstract

MARCHIOLI and LEVANTESI (1)Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti, Italy.  marchioli@negrisud.it  (2)Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti, Italy; Coronary Care Unit, Cardiologic Department, 'S.Pio' Hospital Vasto, Chieti, Italy reviewing the evidence of the role of  n-3 PUFA’s apparent neutral effects upon cardiovascular (CV) events, argue for the re-consideration of several methodological and clinical aspects of these recent trials.

Background

Many large, randomised clinical trials and some meta-analyses have shown that treatment with n-3 polyunsaturated fatty acids (n-3 PUFAs) is associated with consistent benefits on cardiovascular (CV) events, primarily due to a reduction of coronary and CV deaths in patients with coronary heart disease.

Methodology

At variance with such evidence, some clinical trials and meta-analyses showing a neutral effect of n-3 PUFAs have been recently published, raising concern about the consistency of the evidence on the CV benefits of n-3 PUFAs.

Results

Several methodological and clinical aspects of these recent trials deserve to be considered. Indeed, the low rate of events or the overoptimistic expectations of the benefit of n-3 PUFAs used for sample size calculation led to an inadequate statistical power of several studies. The improvement of background medical therapy, serum baseline levels of n-3 PUFAs, and different doses and/or treatment duration might have downplayed the benefit of n-3 PUFAs.

Conclusion

Similarly to old drugs shown to be effective some years ago, it is possible that the benefits of treatment with n-3 PUFAs are not as great in a modern CV prevention strategy so rich in many effective drugs compared with past trials testing CV drugs when less effective therapies were available.

References

Marchioli R(1), Levantesi G(2). n-3 PUFAs in cardiovascular disease. Int J Cardiol.170(2 Suppl 1):S33-8. Dec 20 2013. doi: 10.1016/j.ijcard.2013.06.042. Epub Sep 62013.