The Mediterranean Diet in Primary Cardiovascular Prevention

The Mediterranean diet, supplemented with either extra virgin olive oil or tree nuts, may have just won a secure seat at the table where cardioprotection and prevention are discussed. The results of the recent study in the New England Journal of Medicine compared 2 Mediterranean-style diets (olive oil or tree nuts) with a control diet (low in saturated fat) found a reduction in major cardiovascular events of 30% among subjects in a large primary prevention cohort over about 5 years. The primary end point was a composite of myocardial infarction, stroke, and death from cardiovascular causes.

• Were any other end-points (eg, HbA1C, LDL-C, hs-CRP, weight) evaluated during the study?

• What underlying mechanism might explain the benefits of the Mediterranean regimen?

• What populations can we extrapolate this data to?

• Why weren’t results of the low-fat diet more robust?

• What is the best advice for primary care physicians who field questions on the study-and on current dietary guidelines-from their patients?

Answering these and other questions in this podcast are CardiologyNow host Dr Payal Kohli and her guest Dr Michael Blaha. Dr Kohli is a cardiology fellow at the University of California San Francisco. Dr Blaha is assistant professor of cardiology and epidemiology, and director of clinical research for the Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, in Baltimore.

Mediterranean Diet in Primary Cardiovascular Prevention

Take-home points

1. Compared with patients eating a low-fat diet, patients consuming a Mediterranean -style diet displayed a 30% reduction in major cardiovascular events.

2. An almost immediate advantage was observed among patients consuming the Mediterranean diet compared to control diet-suggesting that the mechanism underlying the difference is something more subtle that weight loss and lipid control, and may involve inflammation and plaque stabilization.

3. Although trial patients had no known coronary disease, these results are likely generalizable to secondary prevention as well.

4. The control group (ie, low saturated-fat group) consumed a diet with approximately 38% of calories coming from fat (much higher than the AHA recommended low-fat diet); and, while the Mediterranean-style dieters were afforded consistent behavioral counseling, the control group only received the intervention after 3 years in the study. Both factors could have made the between the diets appear larger than it actually was.

5. The Mediterranean diet continues to be an excellent option to help reduce cardiovascular risk, although cost and access to components of the diet may pose significant barriers.

References or Further Reading

Estruch R, Ros E, Salas-Salvado J, et al for the PREDIMED Study Investigators. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med. 2013. Available at : http://www.nejm.org/doi/full/10.1056/NEJMoa1200303.

Kris-Etherton P, Eckel RH, Howard BV, St. Jeor S, Bazzarre TL. Lyon diet heart study: benefits of a Mediterranean-style, National Cholesterol Education Program/American Heart Association step 1 dietary pattern on cardiovascular disease. Circulation. 2001;103:1823-1825 doi: 10.1161/01.CIR.103.13.1823. Available at: http://circ.ahajournals.org/content/103/13/1823.full.pdf+html.