Alcohol Consumption and Mortality From Coronary Heart Disease: An Updated Meta-Analysis of Cohort Studies.
Level 3 - non-randomized controlled study
Meta-analysis of prospective observational cohort studies
PubMed 28499102 · doi:10.15288/jsad.2017.78.375
What was done
Prospective cohort studies evaluating alcohol intake and coronary heart disease (CHD) mortality were identified from bibliographic databases and reference lists. Studies were coded for abstainer misclassification biases, baseline heart health, cohort age, gender, ethnicity, and quality. Mixed models and stratified analyses evaluated CHD mortality risk by drinking category.
What was found
Across all 45 studies, CHD mortality was lower for low-volume drinkers (RR = 0.80, 95% CI [0.69, 0.93]) and all current drinkers (RR = 0.88, 95% CI [0.78, 0.99]) compared to abstainers. However, low-volume consumption showed no significant reduction in CHD mortality in cohorts aged ≤55 years at baseline (RR = 0.95, 95% CI [0.75, 1.21]), in studies controlling for baseline heart health (RR = 0.87, 95% CI [0.71, 1.06]), or in higher-quality studies (RR = 0.86, 95% CI [0.68, 1.09]). For cohorts aged ≤55 years at baseline, former drinkers (RR = 1.45, 95% CI [1.08, 1.95]) and occasional drinkers (RR = 1.44, 95% CI [1.09, 1.89]) exhibited significantly higher mortality risk than abstainers.
Why it matters
This analysis demonstrates that the observed cardioprotective effect of low-volume alcohol consumption in older populations is largely driven by methodological artifacts, such as misclassifying unhealthy former drinkers as abstainers and lifetime selection biases.
Limits
All included data are observational and subject to self-reported exposure misclassification. The abstract does not specify the total number of individual participants across the 45 cohorts or the specific beverage types analyzed.
Cited by
- supports When former drinkers are removed from the non-drinker category, alcohol intake just below one US standard drink per day is associated with a 17% to 18% lower relative risk of ischemic heart disease compared to non-drinkers.