Le thé diminue le taux de mortalité non-cardiovasculaire

[Gilles]

Congrès européen de cardiologie
Les buveurs de thé plus en forme que les buveurs de café

Une étude comparative entre les effets du café et du thé prouve que la boisson des anglais diminue le taux de mortalité non-cardiovasculaire. Par ailleurs, les consommateurs sont plus sportifs et moins accrocs à la cigarette.

Bonne nouvelle pour les amateurs de thé : en boire régulièrement permettrait de réduire les risques de décès non liés aux causes cardio-vasculaires. C’est ce que suggère une étude comparative entre les buveurs de thé et de café, présentée au Congrès européen de cardiologie à Barcelone.

Le thé fait diminuer la pression artérielle
Dirigée par le professeur français Nicolas Danchin de l'Hôpital européen Georges Pompidou (Paris), l’étude porte sur le bilan santé de plus de 130 000 personnes, âgées de 18 à 95 ans entre janvier 2001 et décembre 2008. Toutes ces personnes consommaient régulièrement soit du thé, soit du café.
Au cours de cette période, 727 décès ont été recensés dont 95 liés à des causes cardio-vasculaires. Les recherches de l'équipe du Pr Danchin, ont prouvé que les consommateurs réguliers de thé réduisent leur risque de mortalité non-cardiovasculaire de 24 %, comparé aux buveurs de café. La consommation de thé entraîne également une baisse de la pression artérielle diastolique de 4-5 mmHg . « Boire du thé réduit non seulement les risques de décès non-cardiovasculaires mais aurait aussi une petite tendance à réduire le risque de décès cardiovasculaires », conclut le Pr Danchin.

Moins de tabagisme et de sédentarité chez les buveurs de thé
"Si le risque de mort hors causes cardio-vasculaires est accru chez les accros à la caféine, c’est principalement lié au tabagisme », souligne Nicolas Danchin. En effet, les amateurs de thé fument moins que les autres (29 % contre 34 %.) Ils seraient aussi plus sportifs, surtout les gros consommateurs. L’étude a en effet révélé que l’activité s’intensifie avec le nombre de tasses : les gros buveurs de thé ont un niveau plus élevé (46 % ) que les buveurs modérés (43 %.) Autre conclusion de l’étude : les femmes boivent plus de thé que les hommes et à l’inverse, ces derniers consomment plus de café. Une hypothèse qui rejoint celle du tabagisme puisque sur les 16 millions de fumeurs en France, 31 % des hommes fument quotidiennement contre 24 % des femmes, selon un sondage réalisé en 2012 par l’Institut national de prévention et d'éducation pour la santé.

Le thé est la boisson la plus consommée au monde. Ses vertus antioxydantes sont bien connues : effets bénéfiques sur le cœur et les vaisseaux, baisse du taux de cholestérol... Néanmoins, l’effet antioxydant est considéré comme efficace à partir de 3 à 4 tasses par jour.

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[Gilles]

La communication originale du congrès de Barcelone :

Drinking tea reduces non-CV mortality by 24 percent
PUBLIC RELEASE DATE: 31-Aug-2014



Barcelona, Spain – Sunday 31 August 2014: Drinking tea reduces non-cardiovascular mortality by 24%, reveals a study in 131 000 people presented at ESC Congress today by Professor Nicolas Danchin from France.

Professor Danchin said: "If you have to choose between tea or coffee it's probably better to drink tea. Coffee and tea are important components of our way of life. Their effects on cardiovascular (CV) health have been investigated in the past with sometimes divergent results. We investigated the effects of coffee and tea on CV mortality and non-CV mortality in a large French population at low risk of cardiovascular diseases."

The study included 131 401 people aged 18 to 95 years who had a health check up at the Paris IPC Preventive Medicine Center between January 2001 and December 2008. During a mean 3.5 years follow up there were 95 deaths from CV and 632 deaths from non-CV causes. Coffee or tea consumption was assessed by a self-administered questionnaire as one of three classes: none, 1 to 4, or more than 4 cups per day.

The researchers found that coffee drinkers had a higher CV risk profile than non-drinkers, particularly for smoking. The percentage of current smokers was 17% for non-drinkers compared with 31% in those who drank 1 to 4 cups per day and 57% in those who drank more than 4 cups per day.

Non-coffee drinkers were more physically active, with 45% having a good level of physical activity compared to 41% of the heavy coffee drinkers. Professor Danchin said: "This is highly significant in our large population."

Heavy drinkers of coffee were older than the non-drinkers, with a mean age of 44 compared to 40 years. The differences in blood pressure were small, with heavy coffee drinkers having a slightly lower systolic blood pressure (SBP) and higher diastolic blood pressure (DBP) compared to non-drinkers when adjusted for age.

Tea drinkers had the reverse profile of coffee drinkers, with consumers having a better CV risk profile than non-consumers. One-third (34%) of the non-drinkers of tea were current smokers compared to 24% of those who drank 1-4 cups per day and 29% of those who drank more than 4 cups. Physical activity increased with the number of cups of tea per day from 43% in the moderate tea drinkers to 46% in the heavy drinkers.

Tea had a more marked effect on blood pressure than coffee, with a 4-5 mmHg decrease in SBP and 3 mmHg decrease in DBP in the heavy tea drinkers, compared to non-drinkers, when adjusted for age.

Professor Danchin said: "Overall we tend to have a higher risk profile for coffee drinkers and a lower risk profile for tea drinkers. We also found big differences with gender. Men tend to drink coffee much more than women, while women tend to drink more tea than men."

Coffee showed a trend for increasing CV mortality in the heavy compared to non-drinkers but the effect was not significant. Coffee significantly increased non-CV mortality but the increased risk disappeared when the effect was adjusted for smoking. Professor Danchin said: "The trend for higher mortality in coffee drinkers is probably largely explained by the fact that there are more smokers in the group who drink a lot of coffee."

There was a trend for tea drinking to decrease CV mortality but the effect was not quite significant after adjusting for age, gender and smoking. But tea significantly lowered the risk of non-CV death, with a hazard ratio of 0.76 for tea drinkers compared with no tea at all.

Professor Danchin said: "Tea drinking lowered the risk of non-CV death by 24% and the trend towards lowering CV mortality was nearly significant. When we extended our analysis to 2011 we found that tea continued to reduce overall mortality during the 6 year period. Interestingly, most of the effect of tea on non-CV mortality was found in current or ex-smokers, while tea had a neutral effect in non-smokers."

He concluded: "Tea has antioxidants which may provide survival benefits. Tea drinkers also have healthier lifestyles so does tea drinking reflect a particular person profile or is it tea, per se, that improves outcomes - for me that remains an open question. Pending the answer to that question, I think that you could fairly honestly recommend tea drinking rather than coffee drinking and even rather than not drinking anything at all."

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