Omega-3 fatty acids in cardiovascular disease--an uphill battle

Prostaglandins Leukot Essent Fatty Acids. 2015 Jan;92:41-7. doi: 10.1016/j.plefa.2014.05.004. Epub 2014 May 28.

Abstract

In cardiology, results of recent large intervention trials with eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) supplements were neutral. In contrast, in epidemiologic studies, an inverse relation between clinical events and intake of EPA+DHA was found which was steeper for higher levels of EPA+DHA. A standardized way of determining levels is the Omega-3 Index, which is the percentage of EPA+DHA of a total of 26 fatty acids measured in erythrocytes. According to current criteria, a low Omega-3 Index is a cardiovascular risk factor. What can explain this contradiction? Trial participants were recruited irrespective of their baseline status in EPA+DHA - an important predictor of events. Levels of EPA+DHA have a statistically normal distribution; together with the large inter-individual variability of levels' responding to increased intake, this created a large overlap of EPA+DHA levels between intervention and control groups. Moreover, trial participants were advised to take EPA+DHA supplements with breakfast, frequently a low fat meal, resulting in poor bioavailability. As a result, there is an urgent need for new intervention trials in cardiology, for which participants with a low baseline omega-3 index are recruited, and then treated with individually tailored doses of EPA+DHA to a prespecified target range.

Publication types

  • Review

MeSH terms

  • Animals
  • Cardiotonic Agents / pharmacology
  • Cardiotonic Agents / therapeutic use*
  • Cardiovascular Diseases / drug therapy*
  • Cardiovascular Diseases / metabolism
  • Cardiovascular Diseases / mortality
  • Fatty Acids, Omega-3 / pharmacology
  • Fatty Acids, Omega-3 / physiology
  • Fatty Acids, Omega-3 / therapeutic use*
  • Humans
  • Lipid Metabolism
  • Randomized Controlled Trials as Topic
  • Risk Factors

Substances

  • Cardiotonic Agents
  • Fatty Acids, Omega-3