Many of us have trouble understanding why smokers do not listen to our dire
threats about tobacco use. The reason is that most smokers -- even heavy ones
-- know that the odds are actually with them when it comes down to dying of lung
cancer and other diseases. And when you balance the benefits of tobacco use --
especially for the poor and marginalized -- with the risks, smoking can be
seen as a rational means of coping.
See the following article from Time magazine.
Dennis Raphael, PhD
Associate Professor and Undergraduate Program Director
School of Health Policy and Management
Atkinson Faculty of Liberal and Professional Studies
York University
4700 Keele Street
Toronto, Ontario M3J 1P3
tel: 416-736-2100, ext. 22134
fax: 416-736-5227
email: [log in to unmask]
website: http://quartz.atkinson.yorku.ca/QuickPlace/draphael/Main.nsf/
http://www.time.com/time/magazine/printout/0,8816,435982,00.html
Monday, Mar. 24, 2003
What Are Your Odds?
New math for calculating smokers' lung-cancer risk. Don't flunk
this quiz
By DAVID BJERKLIE
Smoking seems to bring out the inner statistician in people. Sure, smokers know
their habit can lead to lung cancer, but what are the odds it actually will? How
does smoking a pack a day for 20 years compare in risk with smoking two
packs daily for 40 years? And if you quit, how much do your odds improve? The
results of a study published last week in the Journal of the National Cancer
Institute offer smokers some help
? at least with the math. The tricky part is
knowing what to do with the answer.
As you might expect, the risk of lung cancer varies according to when you start
to smoke, how long and how much you smoke, and when you quit. By tracking
the incidence of the disease in 18,172 men and women ages 50 to 69 who had
been or still were heavy smokers, researchers at New York City's Memorial
Sloan-Kettering Cancer Center and Seattle's Fred Hutchinson Cancer Research
Center devised a mathematical model that predicts the likelihood that lung
cancer
will be diagnosed in a smoker within 10 years. You can find the model on the
Web at www.mskcc.org.
Consider the case of a 51-year-old woman who smoked a pack a day from age
14 until she stopped at age 42. The model puts her chances of getting lung
cancer in the next decade at less than 1 in 100. Compare that with a 68-year-old
man who has smoked two packs a day for 50 years and hasn't quit. He has a
1-in-7 chance of getting lung cancer by his 78th birthday. If he quits, his
10-year
risk drops to 1 in 9.
So what's a smoker to think? A 1-in-7 chance of getting lung cancer will scare
some folks into quitting, but you might be tempted to shrug off a 1-in-100
chance
and think to yourself, As long as I quit by 42, I'm O.K. Think again. More
smokers die of heart disease than lung cancer ? not to mention that smokers
have greater susceptibility to emphysema and other chronic illnesses.
A better idea would be to use the risk model to help decide whether to undergo
an experimental screening procedure called low-dose spiral computed
tomography. More and more hospitals are offering this scan in the hope of
catching lung cancer early, thereby improving a fairly dismal survival rate. The
scan can detect nodules too small to be seen on conventional X rays.
So far so good. But the scan also spots a lot of things that are not lung
cancer.
"In up to half of patients screened, the scan will show some lung scar or shadow
that will require further evaluation or surgical biopsy, even though it will
ultimately
be deemed to be harmless," says Dr. Peter Bach of Memorial Sloan-Kettering.
The best candidates for the scan, therefore, are those who already have the
highest risk ? and the most to gain.
Of course, no model, no matter how sophisticated, is foolproof. And this one
won't tell you who should get a lung scan. That's something smokers and
ex-smokers should decide with their doctors. And if you need any more reasons
to quit, consider this: in some ways, a little smoking may be as bad as a lot.
Researchers looking at the lining of blood vessels were surprised to find the
same
damage whether the subjects smoked a pack a day or a pack a week. When it
comes to smoking, the odds are always against you.
Calculate your risk of lung cancer at www.mskcc.org
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