Vin et coeur.

Esculape a posé une bonne question dans un commentaire de ma note sur le café.

Jusqu'à présent, je conseillais aux patients qui me posaient la question, de boire 2 verres de vin par jour.

Sans parler d'effet protecteur, cela ne pouvait pas leur faire de mal.

Mais, y-a-t'il vraiment un effet protecteur?

Beaucoup d'arguments indirects, dont il faut se méfier, sont en faveur, mais en fait, il n'existe aucune étude scientifique digne de ce nom.

J'ai retrouvé cette synthèse dans theheart.org, qui résume pas mal les choses.

En gros, en français, pour faire plus court: on ne sait pas....

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Experts cautious about protective effect of red wine against heart disease

Julia Rommelfanger

Tue, 23 Jan 2001 18:43:59

   

Dallas, TX - Although a large number of studies have suggested an association between moderate red wine consumption and a reduced risk for cardiovascular disease (CVD), the American Heart Association (AHA) advises physicians to downplay the popular but still unproven hypothesis that drinking red wine could benefit the heart. The AHA has published an advisory from their Nutrition Committee, Council on Epidemiology and Prevention and Council on Cardiovascular Nursing on the current scientific status about "Wine and Your Heart" in the January 23, 2001 issue of Circulation.

A glass or two of wine may be part of a heart healthy lifestyle, according to media reports:

       

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New York, NY - Although most doctors don't tell their patients to drink, some still believe that moderate amounts of wine are acceptable, according to doctors quoted in the media on January 23, 2001. Cardiologist Dr Brian Baldwin (Dallas, TX) told the Associated Press (AP) that he councils patients who drink to do so moderately, but adds: "No doctor emphasizes alcohol to their patients." "It's a very challenging situation," Dr Jeffrey Alexis (Instructor of Medicine, Mount Sinai Medical Center, New York, NY) told ABCNews.com, which adds that "Alexis says some patients do come in after hearing media reports of wine being beneficial and ask if they should start drinking. But because of the potential for negative effects and abuse, says Alexis, doctors are reluctant to recommend alcohol."
Despite the health risks of heavy drinking, moderate wine drinking does have health benefits, Dr R Curtis Ellison (Professor of Medicine and Public Health, Boston University School of Medicine, Boston, MA) told CBSHealthWatch. Ellison believes the AHA advisory is "cautious and conservative": "In my opinion, there's really no question that alcohol is related to a lower risk of heart disease." He points to long-term studies showing moderate drinking to be beneficial. Studies don't prove whether wine is better than other forms of alcohol, Ellison says, or what precisely is in wine that makes it so beneficial, CBSHealthWatch reports, adding, "Other lifestyle factors associated with wine drinking, such as drinking in moderation, drinking with meals, or having an overall healthy lifestyle could also explain some of the benefits of wine over other types of alcohol."

- Mark L Fuerst

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"Without a large-scale, randomized, clinical endpoint trial of wine intake, there is little current justification to recommend alcohol (or wine specifically) as a cardioprotective strategy," writes the advisory panel, headed by Dr Ira J Goldberg (Columbia University).

Lack of decisive evidence
Numerous population-based surveys support the hypothesis that people who drink one to two glasses of red wine per day have a lower CVD risk than nondrinkers. Moreover, in certain parts of Europe where wine is consumed frequently, CVD mortality is an estimated 50% lower than in the US, despite an otherwise similar high-fat diet. Despite this observation, a phenomenon called the "French paradox," the AHA is cautious about attributing this reduced CVD rate to red wine alone, because study data regarding its effects on the cardiovascular system have not been consistent. The supposed cardioprotective effect of red wine requires further investigation, say Goldberg et al, because "the pattern of consumption of alcoholic beverages may be a marker for other lifestyle factors related to heart disease risk." Some European populations, they say, consume diets rich in fruits, vegetables, and fish, which are readily associated with a lower CVD risk.
The best-known biological effect of alcohol on the cardiovascular system is the increase in blood levels of HDL cholesterol, with a 12% increase with 1-2 glasses per day. However, "this increase is similar to that seen with exercise programs and medications," says Goldberg. He points out that niacin therapy can result in an even greater 20% increase of HDL.
Moderate alcohol consumption has also been reported to decrease platelet aggregation. Although some evidence suggests that resveratrol and other polyphenolic compounds found in red wine might independently reduce platelet aggregation, the evidence is still insufficient for red wine to be declared more beneficial than other alcoholic beverages, the advisory team explains. Similarly, the effect of alcohol on other aspects of coagulation, such as a reduction of plasma fibrinogen levels, have been hypothesized, but not substantiated by clinical data.
Another theory suggests that red wine, as an antioxidant, could decrease the development of atherosclerotic plaque. Again, however, study results so far have been conflicting. Thus, this hypothesis also remains unproven, the experts say. In fact, recent interventional studies have failed to demonstrate a cardioprotective effect of the presumed antioxidant vitamin E. "Besides, the same antioxidants found in red wine can also be obtained from unfermented grape juice" or fresh fruit and vegetables, according to Goldberg.

Upsides may not outweigh downsides

A different question the advisory team members raise is whether the potential cardiovascular benefits associated with red wine outweigh its potential health hazards, such as fetal alcohol syndrome, cardiomyopathy, hypertention, stroke, cardiac arrhythmia and sudden death, most of which, however, are associated with long-term, heavy alcohol consumption. But, although moderate red wine intake does not appear to lead to severe adverse events, Goldberg et al advise physicians not to recommend red wine as a cardioprotective strategy until a large-scale trial has documented its benefits.