Pubdate: Thu, 16 Apr 2009
Source: Edmonton Journal (CN AB)
Copyright: 2009 The Edmonton Journal
Author: Pamela Fayerman, Canwest News Service


Consumers Of Both Drugs Run Three Times The Risk Of Lung

People who habitually smoke both tobacco and marijuana are about three
times more likely than non-smokers to develop serious lung disease,
according to results of a British Columbia study.

That affects a lot of people because nearly 20 per cent of
Vancouverites over the age of 40 do or have done just that, according
to the findings of a survey conducted by a team from Vancouver's St.
Paul's Hospital.

People who smoked only cigarettes were 2.7 times more likely than
non-smokers to have chronic obstructive lung disease.

Those who smoke or smoked both cigarettes and marijuana were 2.9 times
more likely to have the disease.

The study, published Tuesday in the Canadian Medical Association
Journal, included nearly 900 Vancouver residents recruited into the
study by random telephone dialing. It showed that 14 per cent of
participants now smoke only pot and 14 per cent smoke tobacco.

Only 38 of the 856 participants now smoke both marijuana and tobacco.
But 160 participants (18 per cent) were either current or previous
users of both

Consistent with previous population surveys showing that B.C. has the
highest marijuana use in the country, 45.5 per cent of participants in
the current study said they had used marijuana in the past.

The study was designed to estimate the prevalence of chronic
obstructive lung disease (COPD) among adults over the age of 40 in the
general population and its associations with smoking.

Researchers from iCapture Centre for Cardiovascular and Pulmonary
Research, a department at St. Paul's, had expected 15 per cent would
have lung disease, but the study found it was 19.3 per cent.

About half of the people with clinical signs of lung disease had not
yet been diagnosed with it -- they found out when they did lung
function tests for the purposes of the study.

Lead author and respirologist Dr. Wan C. Tan said those study
participants were given the results of their tests so they could share
them with their family doctors, get referred for specialist care or,
ideally, "take smoking cessation more seriously."

COPD -- which includes chronic emphysema or chronic bronchitis -- is
often indicated by an ongoing cough with phlegm and wheezing or
shortness of breath.

Tan said COPD is a progressive disease and is the fourth-leading
killer in North America, behind cancer, heart disease and stroke.

In the study, researchers found that participants with COPD had a
greater likelihood of acquiring other illnesses, such as asthma, heart
disease and high blood pressure.

They were more likely to have a history of hospital admission for
respiratory problems.

Marijuana smoking alone did not appear to cause COPD, according to the
study's findings.

Although marijuana-only users had a 1.6 times greater risk of COPD
than non-smokers, Tan said researchers are not convinced of the
statistical power of that odds ratio because there were too few study
participants who used marijuana alone in the COPD group.

Experts have found one marijuana joint is equal to the effects (on
lungs) of 2.5 to five cigarettes.
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MAP posted-by: Larry Seguin