Erectile Dysfunction May Be Early Warning Sign of
Looming Heart Attack for Diabetics
Older men – frequent victims of both diseases –
should be on the alert
May
20, 2008 – Among some older men, it is popular to joke about erectile
dysfunction (ED) and the use of the drugs, like Viagra, that treat it.
But, much of the laughing may come to a halt today after the release of
new studies concluding that for men with type 2 diabetes – mostly senior
citizens - erectile dysfunction may be an early warning alert of a
looming heart attack.
One of the studies also showed that
cholesterol-lowering medications could cut the risk of heart problems by
about one-third - and suggested that Viagra and other compounds in the
same drug family might offer similar protection.
The research, which is published in the May 27,
2008, issue of the Journal of the American College of Cardiology (JACC),
underscores the importance of encouraging men to report ED to their
physicians, and of focusing treatment not only on overcoming sexual
dysfunction but also on improving overall cardiovascular health.
“The development of erectile dysfunction should
alert both patients and healthcare providers to the future risk of
coronary heart disease,” said Peter Chun-Yip Tong, Ph.D., an associate
professor in the Department of Medicine & Therapeutics at The Chinese
University of Hong Kong, Prince of Wales Hospital, Hong Kong.
“Other risk factors such as poor blood glucose
control, high blood pressure, high cholesterol levels, smoking and
obesity should be reviewed and addressed aggressively.”
Diabetes, erectile dysfunction and heart disease
share an ominous link: damage to the blood vessels by high blood sugar
levels. The same process that hinders the extra blood flow needed to
maintain an erection can have even more serious consequences in the
heart.
“The first event is probably endothelial
dysfunction—when the smoothness and reactivity of the blood vessel are
damaged,” said Dr. Tong. “This process encourages local inflammation on
the inner surface of the blood vessels and the deposition of
cholesterol, resulting in formation of clots and atherosclerosis.
Therefore, there is a high risk of blockage of blood vessels in the
heart, which can lead to a heart attack.”
Men typically show signs of ED more than three
years before the onset of symptoms of coronary heart disease. In one
study of diabetic men, symptoms of ED always preceded coronary symptoms.
Is ED warning sign of poor cardiovascular
health?
In the Hong Kong-based study, Dr. Tong and his
colleagues set out to determine whether ED could be used as an early
warning sign of poor cardiovascular health.
Researchers recruited 2,306 men with type 2
diabetes, performing a thorough medical evaluation of diabetic control
and complications, including damage to the kidneys, eyes and
cardiovascular system. At the beginning of the study, just over
one-quarter of the study participants had ED. None of the participants
had any signs or history of heart disease, vascular disease or stroke.
The researchers followed-up the patients for an
average of four years. During that time, 123 men either suffered a heart
attack, died from heart disease, developed chest pain caused by clogged
arteries, or needed bypass surgery or a catheter procedure to restore
blood flow to the heart.
Men who had ED at the beginning of the study were
far more likely to develop one of these signs of coronary heart disease
(CHD) - or a “CHD event” - than were men who initially did not have ED.
Statistical analysis showed that out of every 1,000 diabetic men with
ED, 19.7 could be expected to experience a CHD event each year, as
compared to only 9.5 of 1,000 diabetic men without ED.
The research team then performed an analysis that
included many different characteristics that, like erectile dysfunction,
were associated with the development of CHD, including age, high blood
pressure, the need for cholesterol- or blood-pressure-lowering
medications, the duration of diabetes, and damage to the kidneys or the
eyes as a result of diabetes.
Even when these characteristics were taken into
account, ED was found to be an independent early warning sign of
coronary heart disease.
In fact, ED signaled a 58 percent increase in the
risk of CHD. Only spillage of large amounts of protein in the urine - a
sign of extensive kidney damage—was a stronger warning sign, doubling
the risk of heart disease.
Italian study looks at silent CHD discovered by
stress testing
The second study, conducted by researchers from
four medical centers in Italy, focused on 291 men who not only had type
2 diabetes but also silent CHD discovered by stress testing and
confirmed by x-ray angiography.
Of these, 118 had ED at the beginning of the study.
Lead investigator Carmine Gazzaruso, M.D., Ph.D., and his colleagues
followed-up patients for an average of nearly four years, documenting
major adverse cardiac events (MACE), which they defined as not only CHD
events but also stroke, mini-stroke (transient ischemic attacks) and
arterial disease in the legs.
They found that patients who had ED at the
beginning of the study were twice as likely to suffer a major adverse
cardiac event when compared to those without ED.
The study also showed that among patients who were
taking cholesterol-lowering statins, the risk of MACE was reduced by one
third (hazard ratio, 0.66, p = 0.036). Viagra and other medications in a
family known as 5-phosphodiesterase (5PDE) inhibitors also appeared to
reduce the MACE risk (hazard ratio, 0.68); however this finding was just
beyond the cusp of being statically significant (p = 0.056).
“These are important studies,” said Robert A.
Kloner, M.D., Ph.D., F.A.C.C., a professor of medicine at the Keck
School of Medicine at the University of Southern California, and
director of research for the Heart Institute at Good Samaritan Hospital
in Los Angeles. “While we have known that ED shares many common risk
factors with CHD, such as hypertension, smoking, dyslipidemia and
diabetes, what is new here is that ED remained a significant risk factor
for developing heart disease after controlling for other cardiovascular
risk factors.
“Men should know that ED is a true harbinger of
atherosclerotic coronary heart disease,” he said.
Dr. Kloner, who wrote an editorial about the new
studies in the same issue of JACC, also noted that not only have statins
been shown to reduce the risk of cardiovascular illness in diabetic
patients, controlling blood pressure and other risk factors is also
critical.
“In diabetic patients, it is important to not only
control the blood sugar level, but also to keep blood pressure below
130/80 mmHg and reduce ‘bad’ (low-density-lipoprotein, or LDL)
cholesterol to less than 100 mg/dL. If a patient smokes, a smoking
cessation program is crucial,” Dr. Kloner said.
Dr. Tong said that he and his colleagues are
continuing to analyze a database of nearly 10,000 patients with diabetes
in an attempt to answer several remaining questions about the link
between ED, diabetes and heart disease.
For example, will improvements in the control of
blood sugar and other cardiovascular risk factors reduce the likelihood
of developing erectile dysfunction or suffering a heart attack or other
serious heart disease" Are patients who have ED in addition to
diabetes-related eye problems and kidney problems at higher risk for
death or cardiovascular disease? And if so, how great is the increased
risk?
“All of these questions are relevant to those who
suffer from diabetes,” Dr. Tong said. “The information we find will help
patients to focus on improving their own health.”
Editor’s Notes
Dr. Tong reports no conflicts of interest related
to this topic.
The American College of Cardiology is leading the
way to optimal cardiovascular care and disease prevention. The College
is a 34,000-member nonprofit medical society and bestows the credential
Fellow of the American College of Cardiology upon physicians who meet
its stringent qualifications. The College is a leader in the formulation
of health policy, standards and guidelines, and is a staunch supporter
of cardiovascular research. The ACC provides professional education and
operates national registries for the measurement and improvement of
quality care. More information about the association is available online
at
www.acc.org .
The American College of Cardiology (ACC) provides
these news reports of clinical studies published in the Journal of the
American College of Cardiology as a service to physicians, the media,
the public and other interested parties. However, statements or opinions
expressed in these reports reflect the view of the author(s) and do not
represent official policy of the ACC unless stated so.
Keep up with the latest news for senior citizens, baby
bommers
May
20, 2008 – Among some older men, it is popular to joke about erectile
dysfunction (ED) and the use of the drugs, like Viagra, that treat it.
But, much of the laughing may come to a halt today after the release of
new studies concluding that for men with type 2 diabetes – mostly senior
citizens - erectile dysfunction may be an early warning alert of a
looming heart attack.