Comparing the effects of a Mediterranean versus a low-fat diet in the secondary prevention of cardiovascular events in patients with coronary artery disease.

This study compared the effects of a Mediterranean versus a low-fat diet in the secondary prevention of major cardiovascular events (MACE) in patients with established coronary artery disease (CAD). The data showed that in secondary prevention, the Mediterranean diet was more effective in preventing MACEs compared to a low-fat diet in these patients.

Coronary artery disease (CAD) is a condition in which the blood vessels in the heart become blocked. It increases the risk of cardiovascular disease. It also increases the risk of MACE such as heart attacks, stroke, or death. Treatments given to patients help with or reduce the risk of cardiovascular disease. These treatments can include a combination of lifestyle changes, medications, and surgery.

Dietary changes are a common preventive method. The Mediterranean and low-fat diets are effective in the primary prevention of cardiovascular disease in people who are not known with CAD. The Mediterranean diet includes a high intake of fruits, vegetables, legumes, cereals, white meat, fish, and olive oil. However, the effects of these two diets in the secondary prevention of MACE in patients with established CAD are still unknown.

This study involved 1002 patients with CAD. Patients were randomly assigned into 2 groups. 502 patients were assigned to follow a Mediterranean diet. 500 patients were assigned to follow a low-fat diet. The average follow-up time was 7 years.

Patients in the Mediterranean diet group had a roughly 25-28% lower risk of experiencing recurrent MACE (heart attacks, stroke, or death) than patients in the low-fat diet group.

Significantly fewer MACE occurred in the Mediterranean diet group compared to the low-fat diet group. 

Among the male patients, 16.2% in the Mediterranean diet group experienced MACE compared to 22.8% in the low-fat diet group. Among the female patients, there was no difference between the 2 groups.

This study concluded that in secondary prevention, the Mediterranean diet was more effective in preventing MACE compared to a low-fat diet in patients with CAD.

The study was funded by two organizations that promote the olive oil industry with one of them providing free olive oil for patients. This study was conducted at a single institution in Spain where patients have a higher acceptance of the Mediterranean lifestyle.