Methods:

The Risk and Prevention Study was a double-blind, placebo-controlled clinical trial, which included patients cared for by a network of 860 general practitioners in Italy. Eligible patients included men and women with multiple CV risk factors or atherosclerotic vascular disease, but not myocardial infarction. The criterion of multiple CV risk factors was defined as at least four of the following (or, for patients with diabetes, at least one of the following): age of 65 years or older, male sex, hypertension (clinical history of hypertension or use of antihypertensive treatment), hypercholesterolemia (clinical history of hypercholesterolemia or use of lipid-lowering treatment), status as a current smoker, obesity (a body mass index of 30 or more), or a family history of premature CVD (defined as cardiovascular disease at <55 years of age in the patient’s father or a brother or at <65 years of age in the patient’s mother or a sister). Patients were randomly assigned to n−3 fatty acids (1 g daily) or placebo (olive oil). The predefined specified primary endpoint was the cumulative rate of death, nonfatal myocardial infarction, and nonfatal stroke. At 1 year, after the event rate was found to be lower than anticipated, the primary endpoint was revised as time to death from CV causes or admission to the hospital for CV causes.