SHAPE Recommendations Generate Controversy
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July
25,
2006 -- The recently issued SHAPE
report has stirred up a number
of controversies. The SHAPE (Screening for Heart Attack Prevention
and Education)
Task
Force made up of a number of well-known cardiologists and
cardiac imaging
specialists,
among them a Past President of the American College of Cardiology,
issued a guideline two weeks ago for noninvasive screening of all
men between
ages
of
45 and
75
and
women between
ages of
55
and
75 to
assess
the calcium in their coronary arteries, also called subclinical
atherosclerosis, using a Calcium Scoring CT scan, as well as their
carotid wall thickness, using
ultrasound
imaging
-- even
though
they
have no symptoms of coronary artery disease.
The report was issued against the
background of current guidelines for risk assessment, which mainly
follow the Framingham Risk Score that
long has been used to rate the level of risk of developing
heart disease, based on factors such as cholesterol levels, lifestyle
choices (diet and smoking), family history and a range of others.
The SHAPE recommendations differ in that they call for the direct
observation of arterial disease,
as opposed to calculating "risk factors".
These recommendations were
characterized in one medical publication as "a
bold new report", yet in another they were labeled
as "scientifically
extremely questionable" and they "should be repudiated".
In the public realm, today's Boston Globe ran a feature story questioning
the apparent conflict of
interest involved by
who paid for the publication of the guidelines, which ran as a
supplement in the July 17 issue of the American Journal of
Cardiology.
The supplement was funded by Pfizer, manufacturer of Lipitor, a
statin
drug that the newspaper pointed out might be prescribed
much more widely to all the new coronary artery disease patients
found
by
the advocated
screening. Dr.
Harvey Hecht, Director of Cardiovascular CT at Lenox Hill Heart
and Vascular
Institute of New York and one of the members of the SHAPE Task
Force, told Angioplasty.Org, "I'm quite pleased by all the controversy
it's elicited -- at least
it brings it into the public eye." He also called the allegations
of conflict-of-interest leveled in the Boston Globe article "absolutely
insulting" and described the Task Force's motivation for issuing
the report:
"All of us involved
in it feel that the current evaluation of risk is woefully
inadequate and you can do just about as well, particularly
in the intermediate
risk population, by flipping a coin.... We know that risk
factors do not equate to disease. So it makes much more sense
to look at each patient as an individual
and determine whether or not whatever has gone on in his life,
whether or not he has risk factors, has affected his
arteries. It's a very simple concept. If a patient is
free of subclinical
atherosclerosis, he's at low risk. If he has extensive subclinical
atherosclerosis, he's at high risk, and this has been demonstrated
in a remarkable number of studies and in thousands of patients."
While
many cardiologists felt that the call for increased screening
could be helpful, several
were
circumspect. Dr. Robert Califf of Duke Clinical Research Institute
stated to theheart.org:
"...it's
not a guideline that's been vetted through any kind of ecumenical group
of people who have any official standing to make clinical-practice
guidelines...there's
enough evidence to have an opinion about this; I don't
think there's enough evidence to have a policy about it."
Others, like Dr. Philip Greenland,
MD, chairman of the Department of Preventive Medicine at the
Feinberg School of Medicine, Northwestern University in Chicago,
were more critical, as he stated to Medscape:
"...this SHAPE report, from
a group that apparently has no oversight
or
outside input or review, which also offers no framework
for its recommendations, and which also provides almost no
scientific
support
for its recommendations, is an apparent effort to subvert
the long-standing evidence-based guidelines approaches of the
[AHA,
ACC, NHLBI]."
Bolstering the direction that the
SHAPE task force took was one of the most prestigious cardiologists
in the profession, Dr. Valentin Fuster, head of no less than two
cardiovascular institutes at New York's Mt. Sinai Hospital and
Past President of the American Heart Association. In an accompanying
foreword to the guideline, Dr. Fuster stated:
"Despite questions
regarding the feasibility and practicality of such an
ambitious
proposal,
the
SHAPE Guideline is a worthy and timely effort that goes beyond
traditional risk assessment and has the potential to transform
the field of preventive cardiology. The driving passion and
commitment of the members of the SHAPE Task Force is commendable.
It serves
as an example to all of us who wish to stop and reverse the
epidemic of atherosclerotic cardiovascular disease."
Where the SHAPE guideline differs
from traditional practice is in how to identify those
at risk. As Dr. Daniel Berman of Cedars-Sinai
Medical Center, another Task Force member, told Angioplasty.Org:
"Half of cardiac
events are occurring in patients who have no symptoms...and
our therapies are really good in preventing heart attacks.
We just have to identify the people who need those therapies.
There have been several studies now that document that it's
not enough
to rely on Framingham scoring for this purpose. I would
hope that the SHAPE guidelines would be embraced, so that
we could
use the
full potential of the examination to do our best to
eradicate heart attacks."
To a great extent, the SHAPE report
was issued out of frustration by physicians who see images on a
day-by-day basis, images of patients who already have or who are
at significant risk for developing blockages in their coronary
arteries,
but who
have
experienced no symptoms and who have scored low on the Framingham
risk assessment. These cardiologists and radiologists know
that new imaging
technologies have been developed and they are anxious
to affect the way patients are diagnosed -- in their view, more
accurately, by using these new tools.
The national
organizations, such as the American College of Cardiology
(ACC), American Heart Association (AHA), etc. historically
have authored
professional
guidelines -- these tend to be relatively conservative,
making sure recommendations are not only safe, but efficacious,
and proven through a number of studies and clinical trials. Reportedly
the ACC/AHA are working on new guidelines for imaging technologies,
to be issued in the fall. One of the criticisms of the SHAPE report
is that it isn't "evidence-based", that this it hasn't been shown
whether the advocated Coronary Calcium Score screening will affect
patient outcomes and save lives. Dr. Hecht counters:
"There is no data provided in
the purely scientific way that these critics would like that
shows
that echocardiography affects the outcome in congestive heart
failure or in any disease, that stress testing affects the
outcome in coronary
disease, that cardiac catheterization and stenting affects
the outcome in any situation other than in acute coronary syndrome,
that electrocardiography affects outcomes. These are basic
tools
which tell us about anatomy, physiology, perfusion, the electrical
issues dealing with the heart, Nobody has ever done a study
that demonstrates that any one of those basic techniques that
we use
every day affects outcome. So why are we asking for a study
showing that a tool that demonstrates subclinical
atherosclerosis...affects outcome? We're asking for
evidence-based medicine in this arena, but we've not
asked for it in other arenas
that cost infinitely greater amount of money and that are basically
entirely unregulated.
Besides which, such a study
would be absolutely unethical because there are so much
data saying
that patients
with high calcium scores have very high risk that it would
be unethical not to use the data obtained on that scan which
identifies a high risk patient and not to treat him aggressively.
You could not randomize him to a study based upon his Framingham
risk score alone when you know that, despite his Framingham
risk score, he's at very high risk.
A final concern was expressed
to Medscape by former AHA President Dr. Robert O. Bonow
over the increased radiation from multidetector CT
scanners, reportedly higher than that from standard angiography,
and that this would make it difficult to recommend as a screening
tool. The Boston Globe article also accompanied its critical report
with a very hi-tech 3-D 64 slice CT scan. However, nowhere does
the SHAPE guideline mention the use of multislice CT angiography,
a relatively new imaging technology that gives striking 3-D pictures,
and requires a higher radiation dose, as well as injection of an
iodine-based contrast
dye. The
SHAPE report refers instead to Coronary Calcium Assessment, a much
simpler CT exam that, as Drs. Berman and Hecht
pointed
out, uses much less radiation, almost ten times less than a standard
nuclear stress test, which is done all the time for risk assessment.
As for the Globe's concern about
Pfizer paying for the supplement (the drug firm also gives financial
support to the SHAPE organization's website, along with a number
of other sponsors) the question arises
that if corporate support were not leveraged, how would information
like this be publicized? It's true that the AHA/ACC guidelines
are not
specifically "sponsored" by any company, but those and many other professional
organizations enjoy a not insignificant amount of financial support
from medical
device
and pharmaceutical companies -- usually these corporate grants
are
listed
on their web sites, and a visit to the exhibition halls of any
of the national meetings reveals a very significant
corporate presence. These organizations also have strict rules of disclosure
for speakers and presentations, aware that when financial ties
are hidden there is room for undue influence. Likewise, in the
case of the SHAPE report, the financial support was clearly indicated.
One attribute of Calcium CT scans
much publicized by the AHEA (the
organization headed by Dr. Morteza Naghavi that issued the SHAPE
report) is the image itself. It is assumed that
a patient
who sees
a picture
of coronary calcium in their arteries
will
change
direction, alter their lifestyle, diet, etc. and comply with prescribed
medications. However, it is a long-standing tenet of behavioral
science that "Information Does Not Change Behavior".
And many cardiologists say that it is very difficult to get patients,
who
have already
been identified as being at high risk for heart attack, to do what
they need to reduce their risk factors (how many patients get an
angioplasty
or stent and continue to smoke?). There are not nearly enough
rehabiliation or risk reduction programs readily
available
to patients -- and they question if finding more at risk
patients will change this?
There are many questions to be answered,
and part of the SHAPE task force's purpose seems to be to shake
things up. In the words of Dr. Prediman K. Shah, head of cardiology
at Cedars-Sinai in Los Angeles and leader of the SHAPE Task Force
Editorial Committee:
"With the publication of the
SHAPE guideline, we hope to build a new
momentum
in cardiology
that inspires
physicians
to use modern technologies for the prevention of heart
attack, rather than using expensive technologies only to treat
heart
attack, which is too late and results in too little benefit
to the patient."
Reported by Burt Cohen, July 25, 2006
related
stories on external sites:
Bold
new report calls for blanket screening of all "at-risk" men and
women using CT and carotid ultrasound --Shelley Wood, theheart.org
(subscribers only)
SHAPE
Task Force Recommends Noninvasive Cardiac Screening for Asymptomatic
Adults --Laurie Barclay, MD, Medscape
(subscribers only)
Article
urging heart exams shows conflicting interests --Stephen Smith,
Boston Globe
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