Pubdate: Wed, 18 Jan 2012
Source: Daily Northwestern (IL Edu)
Copyright: 2012 The Daily Northwestern
Contact:  http://www.dailynorthwestern.com/
Details: http://www.mapinc.org/media/109
Author: Daniel Schlessinger

STUDY SUGGESTS LONG-TERM MARIJUANA USE MAY NOT HARM LUNGS

A recent study conducted in part by Northwestern researchers suggests 
that occasional marijuana usage may slightly improve rather than 
decrease lung function.

Dr. Ravi Kalhan, Feinberg associate professor of pulmonary and 
preventive medicine, helped author the study, which was published 
Jan. 11 in the Journal of the American Medical Association.

"The hypothesis was that marijuana use when smoked would be similar 
to tobacco smoke -- that heavy smoking would lead to detriment to 
lung function," Kalhan said. "(The results were) a little unexpected."

When study participants smoked up to seven joint-years (one joint a 
day for seven years), they experienced a statistically significant 
increase in lung function. Even participants who smoked up to 
40-joint-years saw a marked improvement in lung function.

Researchers primarily based at the University of Alabama at 
Birmingham and the University of California, San Francisco led the 
20-year study. The researchers followed 5,115 men and women in four 
U.S. cities and studied their marijuana and/or tobacco usage in 
relation to their lung function.

Although Kalhan said the scientific world has long believed marijuana 
decreases lung function, some NU students who smoke marijuana said 
they disregard this advice. Neither a McCormick sophomore nor a 
Weinberg sophomore said they considered the medical effects before 
smoking. Both requested to be kept anonymous.

"I don't think that people really think the physical damage aspect of 
it affects their decisions," the Weinberg sophomore said. "I think 
most people, when it comes to cannabis use, have hesitation because 
of the psychoactive effects."

The McCormick sophomore said he has had asthma his whole life, but 
his condition did not faze him when considering marijuana.

He said he was around friends who were smoking marijuana, so he did 
not consciously think through the decision.

The first time the McCormick student smoked, he coughed quite a bit, 
but he said that is common for most first-time smokers. He continues 
to occasionally smoke and sometimes cough but said he does not feel 
any breathing differences.

"I don't know if there's a correlation at all, but my asthma since 
age 15 has been getting better every year that I've smoked 
marijuana," the McCormick sophomore said. "I've never had smoker's cough."

As for why marijuana correlates with increased lung function, Kalhan 
said he remains unsure. Some doctors believe marijuana's effects aid 
lung function, he said, but that argument is widely disputed. Still, 
the study's authors note that in cases in which doctors prescribe 
medical marijuana, its use "may not be associated with adverse 
consequences on pulmonary function."

The authors said deep inhalations of marijuana may expand the lungs. 
They also suggested the chest muscles could become stronger by 
training the lungs to breathe deeply.

Chad Larrabee, the manager of a medical marijuana clinic in Denver, 
Colo., said he has never prescribed marijuana for patients with 
respiratory problems. Larrabee said he remains cautious when giving 
out medical marijuana to people with pre-existing breathing issues 
and usually recommends the drug in an edible or a pill form.

Still, he said he believes that THC, the active component of 
marijuana, is able to dilate the lungs, which would have a positive 
effect on asthma and other respiratory issues.

However, Leo Miller, the vice president of clinical support services 
at the Haymarket Center, a Chicago drug abuse intervention center, 
said the risks of addiction to marijuana outweigh the possible 
benefits in most cases. He has seen "a few" patients who had started 
with medical marijuana as a prescription and who ended up addicted to it.

"For many people, there is a benefit to using psychoactive 
substances," Miller said. "Unfortunately, the vast majority of people 
use it to get high and they get addicted."

The Weinberg sophomore said he agrees there is an element of 
addiction when smoking marijuana. He said marijuana has the potential 
to do serious psychological harm if used improperly.

"I've personally found that when I've smoked for days or weeks or 
months at a time and then I stop, I've found myself craving it," he said.
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MAP posted-by: Jay Bergstrom