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S&A
HEALTH REPORT: The Danger of Detection
By Dr. David
Eifrig Jr.
For the past two
years, I have had the pleasure of staying at the Union League in Philadelphia for a week, while attending an annual
review course sponsored by the University
of Pennsylvania. This
year, as last year, the pressure to learn was intense. The daily lectures
began at 7:15 a.m. and ended approximately 12 hours later! Lunch was
provided, but often the scheduled time to eat was shortened because the
morning lecture didn't end on time. Whew… I learned a lot, but most of it
is still sinking in. By the way, if you ever get a chance to learn about
the history of the Union League, I encourage you to do so. Its motto is
"Love of Country Leads." It was founded in 1862 as a society to
support President Lincoln. It is a fascinating place and the employees are
about as loyal as any I have ever met. The Union League is to the movers
and shakers of American politics as The Augusta National is to golf.
Okay, enough of the
travel diary and on to the point. One of this year's speakers at the review
course reminded us of something he said last year. I had apparently ignored
it last year, but this time it hit home in a big way.
According to David Abramson, the first-ever Chief of the
Ophthalmic Oncology Service at Memorial
Sloan-Kettering Cancer Center,
"Diagnostic X-rays cause close to 1% of all deaths in the U.S., and 3.5% of all deaths in Japan."
Moreover, he told us, "You should never let a child get a CT". A CT, or
computer tomography, is essentially a large number of consecutive or serial
X-rays taken all at once and then analyzed
by computers using fancy algorithms. This was jaw-dropping because I myself
have ordered hundreds of CTs on adults and
children. It turns out that terminal cancers that occur years later are not
easily traced back to the earlier exposures.
Suspicions that
radiation from X-rays and CTs cause long-term
health problems have been around for a long time. But because the cancers
are slow-growing and insidious, it has taken a long time to uncover the
real risks. Only in the past 10 years have scientists truly questioned the
benefits versus risks of detection via CT or X-ray.
What this means for
you and me is unclear, but for us as a group the dangers are real.
Researchers at Columbia
University put the
risk for getting cancer at 1 out of 1,000 from exposure to radiation from
the now-commercially available whole-body scans. In addition, the false
positive rates from these machines are high. This means that the scan finds
anomalies that are not truly disease-causing or debilitating. The anomalies
don't need treatment, but they show up on the scans as "positive."
On top of this, these whole-body tests are usually hyped as
health-promoting when, in fact, they are not. Even worse, they are
expensive.
What is scary,
though, is that the studies your doctor might order could easily be useless
as well as dangerous. Yet, we trust our doctor to make these decisions. Be
careful. Is your doctor ordering tests to help with diagnosis, or to CTA
(Cover Their A**)? You see, even if the CT were to pick up a true disease
entity (for example, prostate cancer), there is very little evidence that
early detection in certain diseases (especially slow-growing ones) makes
any difference in quality or length of life. For those with a disease
detected early and no symptoms, the psychological impact of knowing you
have a disease can be spiritually and physically devastating. It is
possible that the psychological impact is more devastating than the disease
would be, and could lead to earlier morbidity and mortality. In fact, a
Mayo study of lung-cancer screening found that people in the screening
group died earlier than those not screened with CTs.
Hmmm.…
In a Japanese study,
CT screenings flagged equal numbers of smokers and non-smokers for lung
cancer. Thus, CTs failed as a screening tool for
cancer in smokers, and worse, put many people at risk for cancer from the
radiation exposure of the CT.
The confounding
variable in all this is that doctors are taught to do things based on
assigning value to a result. So ordering a test and acting on it becomes a
very natural step for doctors. Sometimes they act even if the result is
logically flawed. Surprisingly and dangerously, treating a false positive
from a lab or test result is quite common. Ironically, the real problem
comes when doctors treat a false positive and, seeing improvement, assume
falsely the treatment worked.
This statistic will
blow you away: After 10 yearly mammograms for women 50 years old or older,
the cumulative false positive rate rises to almost 50%. What! How can this
be so? Your doctor certainly won't tell you this. Does your doctor even
know? And what happens is that the poor woman is exposed to more radiation
and more risk of cancers as the doctor tries to figure out whether she
really does have the disease. The key is to assess the risk clinically
before exposing a woman to radiation. The math is slightly complicated, but
by stratifying patients in to pre-test probabilities for disease…the
correct and, hopefully, safest test might be ordered.
The fact is that CTs and the haphazard recommendations to get them when
the clinical signs and symptoms don't warrant them are inexcusable. Just
recently I read of a child getting head CTs when
the clinical suspicions were quite low. The poor child's head was only
exposed to the CT radiation because of the parents' prodding and the
doctor's fear. Again, this is exposure that has been shown to lead to
cancer, and could have been prevented by informed and fearless parents and
doctors. Sadly, most doctors will argue that they have to order them to
avoid being sued, commonly saying that they've never been sued for ordering
a test, only for not ordering one.
When it comes to
radiation... What do I do?
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1.
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I
avoid radiation for myself whenever possible.
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2.
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I
do not let dentists X-ray my mouth.
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3.
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I
do not get chest X-rays for a long-standing cough since I am not a
cigarette smoker.
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4.
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When
considering a CT in a child, I think long and hard about this and discuss
the very real dangers with the parents. If the clinical picture fits, the
CT usually is unnecessary.
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5.
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If
a doctor ever recommended a CT, I would request an MRI (these are
currently thought to be safer than the radiation from CTs).
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Here's to our health,
David Eifrig Jr., M.D., M.B.A.
P.S. Several of you
have written some thoughtful comments on my last piece about generic drugs.
Some have been downright rude and insulting. Ironically, the latter group
has been mainly doctors, to whom I say, "thank you." You have
once again proven my point. You see, one of the main reasons I started
writing this e-mail was because of the frustration I felt when asking
questions of fellow doctors, attendings,
professors, and occasionally medical students. Very few have ever wanted to
engage in seeking truth. Many have just spouted the conventional wisdom of
their generation. Few understand statistics, let alone logic, and many have
pretended to know something that they later refuse to admit was downright
wrong. The Greeks called this "hubris," and even I have fallen
for the siren song of "sounding confident" to patients only to
realize we (the humanity of healers) are totally and utterly clueless about
a topic.
So when an internist
from UCS or a cardiologist from Washington
U. attack me
personally, but don't have any facts or evidence to counter my arguments, I
know I am on the right track. Moreover, claiming to have a superior resume,
or "CV" (as they fancily call it in medical circles), makes me
laugh. Not because mine is better, but because who cares what we did in the
past? What I care about is what we do today and going forward. However, I
must confess that in a fit of fear (of authority, perhaps) I actually
searched Medline, PubMed, and Google to see what
peer-reviewed articles these people had written… hoping to understand their
fields of interest and endeavors. But, alas, they have not been published…
except in Porter's mailbag.
P.P.S. And to those
doctors who have devoted their lives to truth and openness, I send my
encouragement and blessings. To those of you seeking the truth… thank you
for the support.
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