ANAHEIM, Mar 15 (Reuters Health) -- The impotence drug Viagra appears to be
safe for some men with heart disease -- namely, those not taking nitrate drugs,
according to a new report.
But researchers caution that more study is needed to confirm this finding.
Several reports on Viagra (sildenafil citrate, Pfizer Inc.) were presented
here Tuesday at the 49th annual meeting of the American College of Cardiology.
A Swedish team asserts that Viagra is safe and well tolerated in men with
cardiovascular disease as long as they are not on nitrate therapy. Dr. Arne M.
Olsson of University Hospital in Lund reported findings of a study of Viagra in
224 men with erectile dysfunction and heart disease. None of these men was on
nitrate therapy. Some of the patients were prescribed Viagra, while others were
given a placebo or "dummy" pill for comparison purposes.
Olsson said that Viagra "significantly improved erectile dysfunction,"
although 17% of users experienced flushing and 15% experienced headaches that
were "mild to moderate."
Olsson said that four patients in the Viagra group and three patients in the
placebo group developed cardiac complications, but Olsson said that he does not
believe that these were treatment related.
Dr. Murray A Mittelman of Harvard Medical School in Boston, Massachusetts,
reported finding similar results after analyzing the combined results of 53
studies of Viagra use by men with erectile dysfunction but without documented
heart disease. Mittelman's team conducted their study to find out the risk of
heart problems in men resuming intercourse after being prescribed Viagra.
There were 44 nonfatal and 11 fatal heart attacks in Viagra users compared
with 5 nonfatal and 1 fatal heart attack in placebo users. For deaths from any
cause, there were 29 in the Viagra group and 4 in the placebo group. However,
statistical analysis did not show a significant difference between these
numbers.
Mittelman and colleagues conclude that rates of heart attack and death among
men taking Viagra are low. "These data are reassuring and suggest that treatment
of erectile dysfunction and resumption of sexual activity are not associated
with even a moderate increase in cardiac risk," they report.
However, the men in the Swedish and the US studies were not comparable --
one group had established heart disease and erectile dysfunction, the other
group was identified as only having erectile dysfunction.
And findings from Cedars-Sinai Medical Center in Los Angeles, California are
less reassuring. Dr. Babak Azarbal and colleagues looked at data from the US
Food and Drug Administration's post-marketing surveillance of adverse reactions
associated with Viagra. The data included 3,700 men with erectile dysfunction
and heart disease.
There were 1,473 serious adverse events in the studies. Of these, 65% were
deaths, heart attacks or lethal or nonlethal arrhythmias. Death and heart attack
accounted for 57% of the serious complications.
The investigators say that only 12% of the Viagra-associated deaths occurred
in men who were using nitrates. In 67% of the Viagra-associated deaths, men had
no diagnosis of heart disease.
Azarbal and colleagues report that "although concomitant use of nitrates was
associated with significant risk, most deaths occurred in patients not on...
nitrates." They conclude that further studies "are urgently needed to establish
the safety of Viagra."
