Impotentie
vaak indicatie voor hart- en vaatproblemen.
Mannen
met impotentie kunnen beter naar een cardioloog gaan voor mogelijke hart- en
vaatproblemen dan meteen hun probleem “oplossen” met een middel als Viagra
e.d.. Dit concluderen wetenschappers omdat impotentie vaak een gevolg is van
onderliggende vaatproblemen.
Impotence: A Red Flag for Heart Disease
The two share common physiologic pathways,
experts say.
The two share common
physiologic pathways, experts say
-- For men,
flagging potency can be a red flag that something's not right in the cardiovascular system. And experts say men who rush to fix the
problem with impotence drugs may be ignoring a bigger threat to
their health.
"Erectile
dysfunction [ED] is frequently a manifestation of underlying cardiovascular
problems. It even precedes angina -- it can be an early warning, in that
respect," said Dr. Andrew McCullough, director of male sexual health,
fertility and microsurgery at New York University School of Medicine in New York
City.
The advent of Viagra, Cialis and Levitra has put the research spotlight
back on ED, and a series of studies are suggesting that, for most men, the
condition has physiological, not psychological, origins.
Early in 2004,
researchers led by Dr. Alan Bank of the St. Paul Heart Clinic in Minnesota
published a study showing that the arteries of men with ED expanded less
efficiently than men without erectile difficulties -- a possible sign of
underlying heart disease.
McCullough likened
ED to a common plumbing problem: "If you turn on your kitchen faucet and
you don't get any flow, either the faucet's broken or the pipes are
clogged."
For men with
advanced heart disease, the clogged-pipe explanation probably holds true, since
buildup of cholesterol in arteries can greatly reduce blood flow.
But many men with
ED aren't anywhere near this stage of cardiovascular deterioration. For them,
the faucet -- the vessels inside the penis and the smooth
muscle around them -- may be broken on a biochemical level.
"We're
learning that erectile dysfunction is largely due to reduced nitric oxide in the
endothelium, the inner lining of blood vessels," explained Dr. David
Gutterman, professor of medicine at the Medical College of Wisconsin in
Milwaukee.
As blood flow
demands increase (as happens during an erection), the endothelium releases
nitric oxide to help trigger blood vessel expansion.
"Nitric oxide
is very important for normal erectile function," Gutterman said. "It's
also -- and here's the link to heart disease -- very important as an
anti-atherosclerotic agent, resisting 'hardening of the arteries.' "
In that sense, ED
may serve as an early signal that blood vessels elsewhere in the body aren't
expanding as they should, either.
It's no
coincidence, then, that drugs such as Viagra -- which helps increase nitric
oxide levels in the endothelium -- were first studied as possible treatments for
cardiac trouble.
"However, it
was found that these drugs do this better in some organs rather than
others," Gutterman said. "It was found that they work much better for
urological problems than for the heart."
Looking at the
problem from the other side, Bank's team is currently researching whether or not
the statin family of cholesterol-lowering drugs might help fight ED.
"We do know
that statins improve the function of the enzyme,
nitric oxide synthase, that produces nitric oxide inside the blood
vessels," Gutterman pointed out. "That's probably related to the very
mechanism that helps get rid of ED."
In the meantime,
men with erectile difficulties should stop and consider the possible underlying
cause of that dysfunction, McCullough said.
"Initially,
when Viagra was first approved, there were all kinds of direct-to-consumer ads
associating ED with a physiologic process, to convince men that it wasn't just
psychological, and that it might be linked to underlying cardiovascular
disease," he said.
"But now,
there's a minimalization of all that in these ads. So guys who have these
problems just say 'OK, I'll go online and get some Viagra,' " McCullough
said.
But that type of
attitude has its dangers, he said.
"One of the
most serious things, in my mind, is the guy who fails Viagra, Cialis, Levitra.
Because to me, that suggests he's got more serious underlying disease than some
guy for whom it works," he said.
McCullough's
advice? "Go see your doctor."
Gutterman agreed.
"Some folks with undiagnosed heart disease might not get chest pain first, but they'll get erectile dysfunction. It's just
another way of picking up on early coronary disease."
More information
To learn more about ED, visit the American Academy of Family Physicians (familydoctor.org ).(okt. 2004)