Relationship between alcohol intake, health and social status and cardiovascular risk factors in the urban Paris-Ile-De-France Cohort: is the cardioprotective action of alcohol a myth?

Background/Objectives: Observational studies document the inverse relationship between cardiovascular disease (CVD) and moderate alcohol intake. However, the causal role for alcohol in cardioprotection remains uncertain as such protection may be caused by confounders and misclassification. The aim of our study was to evaluate potential confounders, which may contribute to putative cardioprotection by alcohol. Subjects/Methods: We evaluated clinical and biological characteristics, including cardiovascular (CV) risk factors and health status, of 149 773 subjects undergoing examination at our Center for CVD Prevention (The Urban Paris-Ile-de-France Cohort). The subjects were divided into four groups according to alcohol consumption: never, low (<= 10 g/day), moderate (10-30 g/day) and high (>30 g/day); former drinkers were analyzed as a separate group. Results: After adjustment for age, moderate male drinkers were more likely to display clinical and biological characteristics associated with lower CV risk, including low body mass index, heart rate, pulse pressure, fasting triglycerides, fasting glucose, stress and depression scores together with superior subjective health status, respiratory function, social status and physical activity. Moderate female drinkers equally displayed low waist circumference, blood pressure and fasting triglycerides and low-density lipoprotein-cholesterol. Alcohol intake was strongly associated with plasma high-density lipoprotein-cholesterol in both sexes. Multivariate analysis confirmed that moderate and low drinkers displayed better health status than did never drinkers. Importantly, few factors were causally related to alcohol intake. Conclusions: Moderate alcohol drinkers display a more favorable clinical and biological profile, consistent with lower CV risk as compared with nondrinkers and heavy drinkers. Therefore, moderate alcohol consumption may represent a marker of higher social level, superior health status and lower CV risk. European Journal of Clinical Nutrition (2010) 64, 561-568; doi:10.1038/ejcn.2010.61; published online 19 May 2010