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3
Billion Dollar Hoax
By Gina Kolata
An
estimated 12% of Americans aged 65 and older have osteoarthritis of
the knee. A popular operation for arthritis of the knee worked no
better than a sham procedure in which patients were sedated while
surgeons pretended to operate, researchers are reporting.
The
operation, arthroscopic surgery, for the pain and stiffness
caused by osteoarthritis is performed on about 650,000 people in the US
every year, at a cost of about $5,000 per procedure, for a total cost of
3.3 billion dollars every year in the US. It involves making three small
incisions in the knee; inserting an arthroscope, a thin instrument that
allows surgeons to see the joint; and then flushing debris from the knee
or shaving rough areas of cartilage from the joint and then flushing it.
Tests of
knee functions revealed that the operation had not helped, and those who
got the placebo surgery reported feeling just as good as those who had
had the real operation.
Dr. Baruch
Brody, an ethicist at Baylor who helped design the study, described the
surgery as a sham.
The study
dealt only with arthroscopic surgery for osteoarthritis, not with other
common knee operations.
The 180
participants in the study were randomly assigned to have the operation
or to have placebo surgery in which surgeons simply made cuts in their
knees so the patients would not know if they had the surgery.
The
research began when an orthopedic surgeon at the Houston veterans'
hospital, Dr. J. Bruce Moseley, who is now the team physician for
Houston's two professional basketball teams, approached Dr. Wray
suggesting a study that would compare washing the knee joint with
washing and scraping in patients with arthritis.
Dr. Wray
had a bolder idea. "She said, `How do you know that what you are
seeing is not a placebo effect?' " Dr. Moseley recalled. "My response
was, `This is surgery.' She said, `I hate to tell you this, but surgery
may have the biggest placebo effect of all.' "
Placebo
studies of surgery are almost never done. Many doctors consider them
unethical because patients could undergo risks with no benefits. Working
with Dr. Brody, the ethicist, the group tried to make the placebo
treatment no more dangerous than daily life. Still, of 324 consecutive
patients who were asked to participate, 144 declined.
For those
who agreed, the day of surgery meant being wheeled into an operating
room while neither they nor any of the medical staff knew what their
treatment would be. When they were on the operating table, Dr. Moseley,
who did all the operations, opened a sealed envelope telling him whether
the patient was to have the surgery or not.
Those in
the placebo group received a drug that put them to sleep. Unlike those
getting the real operation, they did not have general anesthesia.
Dr.
Moseley made small cuts in their knees to simulate an operation. He bent
and straightened the knee and asked for surgical instruments, just in
case the patient was partly conscious. An assistant sloshed water in a
bucket to make the sound of a knee being flushed clean.
The paper
in The New England Journal is accompanied by two editorials. One, by Sam
Horng and Dr. Franklin G. Miller of the National Institutes of Health,
asks whether placebo surgery is unethical. The controversy, they wrote,
comes because doctors assume that patients in clinical research should
not be put at risk if they cannot benefit, and placebo surgery involves
risk.
But, they
say, clinical research is different from medical therapy; its aim is not
to help those in the study but to help future patients. To be
ethical, they say, a study with placebo surgery must meet three
criteria: it must not place patients at undue risk; the benefits of
learning whether the surgery works must be worth any potential risk to
the patients; and the patients must give informed consent.
In the
current case, they wrote, all those objectives were met and the study
"exemplifies the ethically justified use of placebo surgery."
New York Times July 11, 2002
The New England Journal of Medicine July 11, 2002;347:81-88, 132-133
Stephanie Thompson's comments:
The title of
this piece is a little harsh, because 'hoax' implies intentional
deception. This is unlikely in the vast majority
of cases. Most medical professionals are very well intentioned and, in
this case in particular, one can understand surgeons'
expectations that the procedure could benefit patients.
However, it
is very telling, isn't it? The notion of evidence-based medicine
requires that all interventions be proven, by well designed trials, to
be substantially more effective than placebo. Surgery, in
particular, often falls dramatically short of this ideal. This is
partly due to the substantial practical challenges of running surgical
placebo trials, but also, yes, because there has been far much too much
assuming going on.
An underlying
principle in placebo science is that the more 'song and dance' involved in
an intervention, the stronger the placebo effect tends to be. Thus
procedures and medicines which produce unpleasant side effects may have
larger placebo effects. Larger pills tend to produce larger
placebo responses than smaller pills. Surgery, of course, is a
particularly dramatic intervention which should be expected to create
among the largest of placebo effects.
However,
evidence-based medicine is much easier said than done, especially for
health practitioners in the field (as opposed to in a lab, academic
office or legal practice). What is a doctor to do when faced with
a patient in obvious pain? He/she doesn't have the luxury of
running a quick placebo controlled trial on 300 people with precisely
the same condition, and following them up for three years, before making a
therapeutic recommendation.
What does
this all mean for clinical practice? I have three thoughts:
1. Question,
question, and question some more. Never assume that what you read, what
you are told by grey-haired professors with certificates, or what you
currently believe, are necessarily correct. Knowledge is a
moving target.
2. Do not make assumptions about cause and effect. A given effect can have
a number of causes, so consider all possibilities.
3. Ask "What can
be done to ethically harness the remarkable self-healing power of
patients, to minimise their subjection to unnecessary stress, risk and
costs of surgery?" (Ideas welcome!!)
