PREDIMED Trial revisited
The PREDIMED study has been retracted, and then republished after concerns were raised about baseline data distributions which may have led to misinterpretation or statistical error. The study evaluated the effect of the Mediterranean diet supplemented with extra-virgin olive oil, nuts or control (advice to reduce dietary fat) on cardiovascular outcomes in 7447 subjects (55 to 80 years of age, 57% women) who were at high cardiovascular risk, but with no clinically evident cardiovascular disease at enrollment. The primary end point was a major cardiovascular event (myocardial infarction, stroke, or death from cardiovascular causes). In this republished version, absolute event rates after a median follow-up of 4.8 years were 3.8% in the group assigned to a Mediterranean diet with extra-virgin olive oil, 3.4% in the group assigned to a Mediterranean diet with nuts, and 4.4% in the control group. In intention-to-treat analyses, there was a 31% relative reduction in the primary endpoint (hazard ratio 0.69, 95% confidence interval [CI], 0.53 to 0.91) in the group assigned a Mediterranean diet with extra-virgin olive oil, and 28% reduction in the group assigned a Mediterranean diet with nuts (hazard ratio 0.72, 95% CI, 0.54 to 0.95), compared with the control diet. The results were similar when data from 1588 subjects in whom study-group assignment was known or with protocol variations were excluded. These new findings were generally similar to those previously reported. The overall process, however, has raised concerns about other errors in the data that may not have been properly accounted for in the analysis.
Primary prevention of cardiovascular disease with a Mediterranean Diet supplemented with extra-virgin olive oil or nuts.
Estruch R, Ros E, Salas-Salvadó J et al