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 (<or=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.
Light-to-moderate alcohol consumption has been previously associated with a lower risk of acute myocardial infarction (AMI) and mortality. The association of changes in drinking behavior after an AMI with health status and long-term outcomes is unknown. Using a prospective cohort of patients with AMI evaluated with the World Health Organization's Alcohol Use Disorders Identification Test, we investigated changes in drinking patterns in 325 patients who reported moderate drinking at the time of their AMI. One-year alcohol consumption, disease-specific (angina pectoris and quality of life) and general (mental and physical) health status and rehospitalization outcomes, and 3-year mortality were assessed. Seattle Angina Questionnaire Angina Frequency and Quality of Life, Short Form-12 Mental and Physical Component Summary Scales were modeled using multivariable hierarchical linear models within site. Of the initial 325 moderate drinkers at baseline, 273 (84%) remained drinking and 52 (16%) quit. In fully adjusted models, Physical Component Scale scores (beta 6.47, 95% confidence interval 3.73 to 9.21, p <0.01) were significantly higher during follow-up in those who remained drinking. Persistent moderate drinkers had a trend toward less angina (relative risk 0.65, 95% confidence interval 0.39 to 1.10, p = 0.11), fewer rehospitalizations (hazard ratio 0.79, 95% confidence interval 0.44 to 1.41, p = 0.42), lower 3-year mortality (relative risk 0.75, 95% confidence interval 0.23 to 2.51, p = 0.64), and better disease-specific quality of life (Seattle Angina Questionnaire Quality of Life, beta 3.88, 95% confidence interval -0.79 to 8.55, p = 0.10) and mental health (Mental Component Scale, beta 0.83, 95% confidence interval -1.62 to 3.27, p = 0.51) than quitters. In conclusion, these data suggest that there are no adverse effects for moderate drinkers to continue consuming alcohol and that they may have better physical functioning compared to those who quit drinking after an AMI.