BMJ 2000;320:1378-1379 ( 20 May )
A paper was published in the BMJ on the 20th May by Martin Bobak,
Senior Lecturer of Epidemiology and public health at University
College London and Zdenka Skodova from the Department of preventative
cardiology at the institute of Clinical and Experimental Medicine
in Prague. The paper, entitled 'The Effect of beer drinking on
risk of myocardial infarction: population based case-control study'
analysed the protective effect of ethanol versus different drink
Many studies have shown an inverse association between alcohol
consumption and coronary heart disease, with a possible flattening
at higher consumption levels.1 It remains unclear, however, whether
the protective effect is confined to specific beverages (such
as red wine) or relates to ethanol. This question is complicated
because wine drinkers may differ from people drinking other beverages
or have a different drinking pattern.They addressed this issue
by conducting a study in the Czech Republic, a predominantly beer
drinking country, and by restricting the analyses to people who
did not drink wine or spirits.
A population based case-control study in five Czech districts
of men aged 25-64 who had a first non-fatal myocardial infarction
that fulfilled the World Health Organization MONICA (monitoring
trends and determinants in cardiovascular disease) criteria of
definite or probable infarction2 over 18 months were considered
eligible. All cases agreed to participate in the study. An age
stratified random sample of the population (response rate 77%)
served as controls. Data on cases and controls were collected
by identical protocols
Participants reported the frequency of drinking any alcohol (never;
less than once a month; once or twice a month; several times a
week; almost daily or daily; and twice a day or more often). They
also reported how much wine, spirits, and beer they consumed during
a typical week. The average consumption of pure alcohol was 148
g a week, 87% of which was consumed as beer. The analyses were
restricted to non-drinkers and "exclusive" beer drinkers.
Participants were categorised into four groups according to their
average weekly intake of beer: <0.5 l (about 18 g of alcohol),
including non-drinkers; 0.5-3.9 l (18-144 g of alcohol); 4-8.9
l (145-324 g of alcohol); and 9 l (325 g of alcohol).
The lowest risk was found among men who drank almost daily or
daily (adjusted odds ratio 0.38, 95% confidence interval 0.19
to 0.75) and among men who drank 4-8.9 l of beer a week (0.34,
0.19 to 0.61) (table 1). When beer intake was analysed in narrower
categories, the lowest risk was found for weekly consumption of
5-6 l, but because of the small numbers of subjects in each category
the confidence intervals were wide (not shown). The results did
not change when men with a history of heart disease, stroke, diabetes,
or cancer were excluded.
In this study of beer drinkers, the lowest risk of myocardial
infarction was found among men who drank almost daily or daily
and who drank 4-9 litres of beer a week. There was a suggestion
that the protective effect was lost in men who drank twice a day
or more. This is similar to results of studies of other beverages.
These results support the view that the protective effect of alcohol
intake is due to ethanol rather than to specific substances present
in different types of beverages.
Funding: The study was funded by a grant from the Wellcome Trust
and by the Czech Ministry of Health. MB was supported by the Wellcome
Trust fellowship in clinical epidemiology. MM is supported by
an MRC research professorship.
Source: Bobak et al BMJ 2000: 320: 1378-1379 (20th May 2000)