Alcohol consumption is associated with a lower incidence of acute myocardial infarction: results from a large prospective population-based study in Norway

Aims: Compelling evidence suggests that light-to-moderate alcohol consumption is associated with a reduced risk of acute myocardial infarction (AMI), but several issues from previous studies remain to be addressed. The aim of this study was to investigate some of these key issues related to the association between alcohol consumption and AMI risk, including the strength and shape of the association in a low-drinking setting, the roles of quantity, frequency and beverage type, the importance of confounding by medical and psychiatric conditions, and the lack of prospective data on previous drinking.

Methods: A population-based prospective cohort study of 58 827 community-dwelling individuals followed for 11.6 years was conducted. We assessed the quantity and frequency of consumption of beer, wine and spirits at baseline in 1995-1997 and the frequency of alcohol intake approximately 10 years earlier.

Results: A total of 2966 study participants had an AMI during the follow-up period. Light-to-moderate alcohol consumption was inversely and linearly associated with AMI risk. After adjusting for major cardiovascular disease risk factors, the hazard ratio for a one-drink increment in daily consumption was 0.72 (95% confidence interval 0.62-0.86). Accounting for former drinking or comorbidities had almost no effect on the association. Frequency of alcohol consumption was more strongly associated with lower AMI risk than overall quantity consumed.

Conclusions: Light-to-moderate alcohol consumption was linearly associated with a decreased risk of AMI in a population in which abstaining from alcohol is not socially stigmatized. Our results suggest that frequent alcohol consumption is most cardioprotective and that this association is not driven by misclassification of former drinkers.