Key Mediterranean Diet Trial Retracted

[Mito]

Key Mediterranean Diet Trial Retracted

The landmark PREDIMED randomized trial of a Mediterranean diet has been influential and highly cited since its 2013 publication in the New England Journal of Medicine. But now it has been retracted and republished after hidden protocol changes and randomization violations came to light.

The tip-off came from an analysis of randomized trials looking for improbable distributions of baseline data, with PREDIMED flagged for variables inconsistent with randomization, according to an editor's note appearing with the retraction.


https://www.nejm.org/doi/full/10.1056/NEJMc1806491

Because of irregularities in the randomization procedures, we wish to retract the following article: Primary Prevention of Cardiovascular Disease with a Mediterranean Diet. N Engl J Med 2013;368:1279-90. DOI: 10.1056/NEJMoa1200303.1 We have reanalyzed the data and have published a new report: Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. N Engl J Med. DOI: 10.1056/NEJMoa1800389.2

 

[Westside PUFAs]

The heart disease diet.

 

[Mito]

Errors Trigger Retraction Of Study On Mediterranean Diet's Heart Benefits

“So in 2013, many took notice of a study in the New England Journal of Medicine that seemed to provide some proof. The study found that people eating the Mediterranean diet supplemented with olive oil were 30 percent less likely to experience a heart attack, stroke, or death from cardiovascular causes than people assigned to a low-fat diet. People who stuck with a Mediterranean diet supplemented with mixed nuts had a 28 percent lower risk than those asked to follow a low-fat diet.

But the New England Journal of Medicine retracted the paper Wednesday because of problems in the way the study was carried out.

A retraction is a last resort for medical and scientific journals, a sign to readers that the results are no longer trustworthy and are beyond correcting. Although retractions are relatively rare — taking down fewer than 1 in 1,000 published articles — the rate is increasing.

“The revised paper says only that people eating the Mediterranean diet had fewer strokes and heart attacks, not, as the original paper claimed, that the diet was the direct cause of those health benefits.”

 

[x-ray peat]

“The revised paper says only that people eating the Mediterranean diet had fewer strokes and heart attacks, not, as the original paper claimed, that the diet was the direct cause of those health benefits.”

I think that person who wrote that article critical of the paper is making too much of the change. If you look at the two papers side by side the number of adverse events didnt change between groups but only a couple of statistical descriptors changed by a small amount, which were well within the margin of error.

Despite some departures from the randomization protocol, most of the baseline covariates were balanced across groups, and there was no meaningful difference in the predicted risks of future cardiovascular events across the three groups (Fig. S13 in the Supplementary Appendix).

We reanalyzed the data using methods that do not rely exclusively on the assumption that all the participants had been randomly assigned to intervention groups and that adjusted for baseline characteristics and propensity scores estimating probabilities of assignment to each intervention on the basis of 30 baseline covariates. The results of our reanalyses (Figure 2 and Figure 3 and Table 3, and Figs. S2 and S4 in the Supplementary Appendix) were similar to the results that we originally reported. In addition, reanalyses of our data did not reveal any evidence that certain lifestyle or treatment factors that are potentially related to the risk of cardiovascular disease either biased the results or might provide an alternative explanation for the observed benefits of the Mediterranean-diet interventions on cardiovascular disease. Analyses that excluded participants whose assignment to an intervention group was known or suspected not to have followed the randomization protocol (participants from Sites D and B and second household members) yielded results consistent with the results of our primary analysis.

Im not recommending the diet but I think it is much better than what people usually eat.

 

[Mito]

Mediterranean diet named the best for 2019 - CNN

 

[thomas00]

Feels like that evidence bar just keeps getting lower.

 

[bboone]

something you notice when visiting the mediterranean countries is that the young people seem very healthy and virile, but once people turn 50, they appear to deteriorate very quickly. both men and women seem to lose at least a head of height, and they shrink into old pruneforms that have to be lead around like livestock, herded from one café to another. here in scandinavia, the old people often retain their height and some sense of dignitity... people used to look much healthier here, though. looking at old family photographs, i don't see a single balding person, despite the age and everyone is taut and lean with dark skin and coarse facial hair. this may be phenotype specific, though, but i don't really see many people who walk around looking like that nowadays...

 

[MigFon]

something you notice when visiting the mediterranean countries is that the young people seem very healthy and virile, but once people turn 50, they appear to deteriorate very quickly. both men and women seem to lose at least a head of height, and they shrink into old pruneforms that have to be lead around like livestock, herded from one café to another. here in scandinavia, the old people often retain their height and some sense of dignitity... people used to look much healthier here, though. looking at old family photographs, i don't see a single balding person, despite the age and everyone is taut and lean with dark skin and coarse facial hair. this may be phenotype specific, though, but i don't really see many people who walk around looking like that nowadays...

Have you considered the possibility that the older people were significantly shorter, even in their youth, compared to the young people of today?

Protein intake is significantly higher nowdays compared with my father's generation for instance, that probably explains why I am 10/15cm taller than my father for instance.

By the way, there is no such thing as a Mediterranean Diet. What people eat/ate in Spain/Portugal/Greece/Itally is significantly different from country to country and includes/has included more saturated fat and meat if/when available.

 

[bboone]

Have you considered the possibility that the older people were significantly shorter, even in their youth, compared to the young people of today?

Protein intake is significantly higher nowdays compared with my father's generation for instance, that probably explains why I am 10/15cm taller than my father for instance.

By the way, there is no such thing as a Mediterranean Diet. What people eat/ate in Spain/Portugal/Greece/Itally is significantly different from country to country and includes/has included more saturated fat and meat if/when available.

i get what you mean and protein quality and intake is certainly a factor in height, but i mean people of seriously diminished stature. i know people were shorter in general a couple of generations ago, but not 30-40 cm... that is the extreme, though. and yes, there is of course no "set" mediterranean diet, but i would still argue there are quite a few similarities within certain areas of the mediterranean. as you said, there's huge variation, with the diet in piedmonte for example being completely different from the diet of sicily, etc.

another thing i find quite strange about statistical studies regarding the mediterranean region is that this is supposedly the area in europe with the most balding men. now, i haven't been everywhere in the mediterranean, but i've been quite a few different places in italy, spain and greece (including crete), and this statistical claim is completely at odds with what i observed. there were barely any bald men, whereas in scandinavia, germany and the british isles there are tons

 

[Richiebogie]

here in scandinavia, the old people often retain their height and some sense of dignitity...

I won't ask what that involves!

 

[MigFon]

i get what you mean and protein quality and intake is certainly a factor in height, but i mean people of seriously diminished stature. i know people were shorter in general a couple of generations ago, but not 30-40 cm... that is the extreme, though.

Protein is the nutrient better correlated with height.

I understand what you are saying. My grandparents were 20/30 cms shorter than me, even when perfectly upstraight, and a few older people in my hometown were 40/50 cms shorter than me. They went through a lot of food restrictions back in the dictatorship days.

What Mediterranean countries have you been at?