The cardioprotective association of average alcohol consumption and ischaemic heart disease: a systematic review and meta-analysis.
OBJECTIVE
Most, but not all, epidemiological studies suggest a cardioprotective association for low to moderate average alcohol consumption. The objective was to quantify the dose-response relationship between average alcohol consumption and ischaemic heart disease (IHD) stratified by sex and IHD end-point (mortality versus morbidity).


METHODS
A systematic search of published studies using electronic databases (1980-2010) identified 44 observational studies (case-control or cohort) reporting a relative risk measure for average alcohol intake in relation to IHD risk. Generalized least-squares trend models were used to derive the best-fitting dose-response curves in stratified continuous meta-analyses. Categorical meta-analyses were used to verify uncertainty for low to moderate levels of consumption in comparison to long-term abstainers.


RESULTS
The analyses used 38,627 IHD events (mortality or morbidity) among 957,684 participants. Differential risk curves were found by sex and end-point. Although some form of a cardioprotective association was confirmed in all strata, substantial heterogeneity across studies remained unexplained and confidence intervals were relatively wide, in particular for average consumption of one to two drinks/day.


CONCLUSIONS
A cardioprotective association between alcohol use and ischaemic heart disease cannot be assumed for all drinkers, even at low levels of intake. More evidence on the overall benefit-risk ratio of average alcohol consumption in relation to ischaemic heart disease and other diseases is needed in order to inform the general public or physicians about safe or low-risk drinking levels.
Public Health and Regulatory Policies, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario, Canada. m.roerecke@web.de
Michael
M
Roerecke
Jürgen
J
Rehm
D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000401:mortality*; D016022:Case-Control Studies; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D017202:Myocardial Ischemia / Q000401:mortality*; D011379:Prognosis; D017678:Sex Distribution