Medical Chronicle November/December 2013 | Page 26

CARDIAC

Binge drinking and vascular function
Binge drinking is a health problem,
especially in college students. It is
defined as consuming four to five
standard drinks in a two-hour period.
There is retrospective data indicating
that binge drinking could be associated
with cardiovascular events such
as stroke, sudden cardiac death,
myocardial infarction and even an
increased mortality after a myocardial

infarction. There could be several
mechanisms involved in these events,
but it is plausible that endothelial
dysfunction could be important, as
it is known that the endothelium is
an important regulator of vascular
function. Endothelial dysfunction
is seen as an early marker of injury
to the blood vessel and subsequent
development of atherosclerosis.

Flow-mediated dilation of
the brachial artery is used to
measure endothelial-dependent
function and nitroglycerinmediated dilation to measure
the endothelial-independent
function of the vascular system.
Endothelial function has not been
measured in young people with
binge drinking behaviour.

New study
This study aimed to
evaluate vascular
function in young
people with binge
drinking and to compare
them to young people
of the same age who
are alcohol abstainers.
College students between
the ages 18-25 years were recruited
into two groups. One group admitted
to binge drinking of >5 drinks within
two hours in the past two weeks. The
control group were students who did
not have more than 1-5 drinks in the
past year.

Method
All subjects had a fasting lipogram,
insulin and glucose levels, C-reactive
protein, blood alcohol levels, blood
pressure, heart rate and oxygen
saturation measured. In addition,
they had a gluteal fat pad biopsy from
which the resistance blood vessels
were isolated for perfused microvascular experiments.
All had a flow-mediated
measurement of the brachial artery
according to the standard method. A
second test was done using sublingual
nitroglycerin tablets and obtaining
brachial images with the same
ultrasound used in the flow-mediated
dilation test.

Results
Men and women binge drinkers had
significantly reduced flow-mediated
and nitroglycerin-mediated dilation as
compared to non-binge drinkers.
The isolated vascular functions
in the resistance arteries were not
different between the two groups.
However, endothelin-1-induced
vasoconstriction was significantly
enhanced in the binge drinkers. There
were no differences between the two
groups in the lipogram, blood pressure
and C-reactive protein.

Conclusions
1. There were important changes in
both macro-vascular and microvascular functions in those that
were binge drinkers.
2. Endothelial dysfunction in binge
drinkers may have early risk of
cardiovascular disease in these
otherwise healthy young people.
3. Binge drinking may be a risk factor
for future clinical cardiovascular
disease in contrast to moderate
regular alcohol consumption that
may be protective.

References available on request.

26 MEDICAL CHRONICLE NOVEMBER/DECEMBER 2013