-
- The fashion for
cocaine may be causing a wave of heart
disease among young people.
Besides its known effect of sending coronary
arteries into spasm, the
drug also encourages the immune system to turn
on healthy cardiac
tissue, researchers in Michigan have discovered.
-
- The work comes as some doctors
are complaining that the
abuse of the drug is causing a hidden drain on
already stretched hospital
resources. They believe that cocaine is
making large numbers of otherwise
fit young people--most of them
men--report to emergency departments with
chest pains.
-
- The immunological
study, led by Benedict Lucchesi of
the University of Michigan in Ann
Arbor, suggests that cocaine activates
a part of our immune defences
called the complement cascade. This system,
which is usually triggered
by invading microorganisms, destroys cells by
building complexes of
proteins on cell membranes, causing the cells to
burst.
-
- Working on rabbit
hearts, the Michigan team has shown
that cocaine boosts the production
of complement proteins, causing the
deadly complexes to form on heart
muscle cells and the endothelial cells
that line the heart's blood
vessels.
-
- So, prompted by Lucchesi's findings, doctors at the University
of Michigan's hospitals are now investigating whether drugs that block
the cascade will help patients suffering from cocaine overdoses.
-
- Michael Davies of St
George's Hospital in London, a cardiovascular
pathologist and assistant
medical director of the British Heart Foundation,
says the Michigan
team's research might explain why some young cocaine
users develop a
form of heart failure in which the heart grows floppy and
pumps blood
less efficiently. "This would fit quite well with the
idea that
complement is damaging blood vessels or heart tissue," he
says.
-
- Larry Alexander of Baylor Medical Center in Dallas, a
drug
abuse spokesman for the American College of Emergency Physicians,
agrees: "The authorities should be doing more to highlight the danger
cocaine poses to people's hearts."
-
- Cocaine can also send coronary
arteries into spasm. Alexander
and other specialists in emergency
medicine believe this is the reason
for a growing number of young
people turning up in hospital complaining
of chest pain. The vast
majority are men, and they are usually discharged
after doctors
establish that they are not suffering from a heart attack.
Each case
has to be thoroughly investigated, however, which stretches hospitals'
resources.
-
- "At the weekend I saw three young males in their
early
twenties with chest pains, and all three were positive for cocaine,"
says Alexander. "Normally it just goes away. But occasionally it gets
very serious and you'll see a heart attack."
-
- The link between chest pain and
cocaine abuse isn't always
clear, says Alexander. And this could mean
that statistics on the number
of emergency hospital visits caused by
cocaine use (see below) are seriously
underestimated. Alexander also
fears that people who repeatedly send their
cardiac arteries into spasm
may suffer long-term heart damage.
-
- John Henry, an expert on drug
abuse at St Mary's Hospital
in London, is similarly concerned. He
suspects that up to 10 per cent of
people reporting to hospital with
chest pain owe their problems to cocaine
abuse. Henry is seeking
ethical approval to carry out anonymous urine tests
for cocaine on
everyone reporting to his hospital with chest pain.
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