Study: Frequent marijuana use tied to reduced bladder cancer risk

[RainDog]

Although presented at a reputable medical association's conference, the study has not yet undergone peer review or been published in a journal. However, the study was composed of 83,000 men and took place over 11 years.

http://www.rawstory.com/rs/2013/05/12/study-frequent-marijuana-use-tied-to-reduced-bladder-cancer-risk/

In findings presented last week at the American Urological Association’s annual conference, researchers announced that the conclusion of an 11-year study has found a strong association between frequent marijuana use and a significantly reduced bladder cancer risk, USA Today reported Saturday.

They found that men who smoke cigarettes multiply their risk of bladder cancer, while men who smoke only marijuana actually lower their risk. Men who smoke both still had an elevated risk of bladder cancer, but it was lower than those who just smoked tobacco.

“Cannabis use only was associated with a 45 percent reduction in bladder cancer incidence, and tobacco use only was associated with a 52 percent increase in bladder cancer,” study author Dr. Anil A. Thomas told the paper.

More amazing still: study participants who used marijuana more than 500 times a year saw even lower bladder cancer risks than those who only used marijuana occasionally. A total of 41 percent of the men studied said they smoked marijuana, while 57 percent smoked tobacco and 27 percent smoked both.

This study's results follow previous studies (published in peer-reviewed, reputable journals) that indicated anti-cancer properties related to cannabis and lung cancer, breast cancer, and brain tumors. You can read about those in the DU Drug Policy Forum.

[kelliekat44]

1. And what about non-smokers? nt

[RainDog]

2. It seems the study was looking at cigarette vs. cannabis

The National Institute of Drug Abuse, for instance, will only fund studies that look into possible harm from things like cannabis or nicotine. I don't know the parameters of this particular study.

[jberryhill]

3. That seems to be covered

"men who smoke only marijuana actually lower their risk"

One would presume that "lower their risk" is in relation to men who smoke nothing.

[randome]

7. If there wasn't a control group of non-smokers, I don't think you can assume that.

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[jberryhill]

8. Hence my use of the word "seems"

As the OP is a press report, and not the paper itself then we are left to context in order to puzzle out what the phrase I quoted might mean.

So we have the phrase "men who smoke only marijuana actually lower their risk", and it is unclear what is the reference in relation to "lower their risk". However, the incidence of bladder cancer in the general population would likely be a known figure.

[RainDog]

11. The non-smokers would not be a control group

if someone were looking into the difference between cigarette smoking and marijuana smoking.

No non-smokers were included b/c the comparison was between cigarettes, which are considered a big factor in the development of bladder cancer, and those who also or only smoked cannabis.

The study compared rates of bladder cancer in the three groups - cigarette smokers only, those who smoked both, cannabis smokers only.

The cannabis smokers only had the best outcomes compared to the other two groups and those who smoked both did better than those who only smoked cigarettes.

The research aligns with prior research that notes the difference, the MAJOR difference, between inhaled cigarettes and inhaled cannabis.

Donald P. Tashkin, MD - Medical Director of the Pulmonary Function Laboratory, Professor of Medicine, University of California, Los Angeles has done the most studies related to cannabis and lung function.

He notes COPD, i.e. emphysema, is not evidenced with cannabis but it is with tobacco. loss of lung function...all lung function for the cannabis users was within the normal function in his large study. The New Zealand study confirmed this. The Arizona study found it might, in the future, lead to COPD.

COPD tends to occur later in life. This is why the study in the OP, a twenty-year study, is considered important b/c of the normal onset of COPD - or decrease in lung function.

Here's a link to a post with videos related to lung function and other health aspects from Dr. Tashkin and also Dr. David Bearman.
http://www.democraticunderground.com/101422478#post101


The Journal of the American Medical Association found that moderate cannabis smokers had BETTER lung function than those who had never smoked cannabis or tobacco.

http://pulmccm.org/2012/asthma-review/infrequent-pot-smokers-have-better-lung-function-than-non-tokers-jama/

Smoking marijuana moderately over years is strongly associated with small improvements in lung function, even compared to people who have never smoked cigarettes or marijuana, according to a study in JAMA. But the popular news media and the study authors downplayed that finding of the study, apparently to avoid sending a pro-marijuana message.

Mark Pletcher, Eric Vittiinghoff, Stefan Kertesz et al crunched numbers from the CARDIA study, which followed 5,115 young U.S. men and women for 20 years (1985-2006) collecting data on tobacco and marijuana use, and included spirometry from 20,777 clinic visits: an enormous trove of longitudinal data.

...in marijuana smokers who had smoked up to 3,650 marijuana cigarettes (10 “joint-years”), FEV1 and FVC were higher than matched nonsmokers. At these common levels of marijuana use, there was a steady dose-response relationship: the more marijuana smoked, the better the lung function (FEV1 increase of 13 mL/joint-year).

All these trends were highly statistically significant (p < 0.001), and supported by the large sample size and body of spirometric data.

[RainDog]

4. Marijuana research faces ridiculous obstacles in the U.S. because of bad policy

http://health.heraldtribune.com/2013/04/20/marijuana-research-funding-cut-as-support-grows/

Overall spending on research has dropped. This drop particularly impacts medical marijuana questions because the research into this aspect of cannabis is blocked by current attitudes in federal agencies.

...U.S. spending has dropped 31 percent since 2007 when it peaked at $131 million, according to a National Institutes of Health research database. Last year, 235 projects received $91 million of public funds, according to NIH data. Regarding cannabis specifically...fewer than 20 randomized controlled trials, the gold standard for clinical research, involving only about 300 patients have been conducted on smoked marijuana over the last 35 years, according to the American Medical Association, the U.S.'s largest doctor group.

Marijuana advocates point out inherent obstacles to conducting research: the National Institute on Drug Abuse controls all the cannabis used in approved trials, but the agency's mandate is to study abuse of drugs, not health benefits.

This creates dilemmas. The Food and Drug Administration, for instance, has approved a clinical trial studying whether marijuana can relieve symptoms of post-traumatic stress disorder. The trial, however, which is in the second of three stages of clinical testing, is blocked. NIDA, which controls the legal testing supply of the drug grown at a University of Mississippi farm, has refused to supply the researchers with marijuana.

Our govt. has put agencies in charge of cannabis who don't want to know anything positive about the plant. They limit access. They deny studies.

This is yet one more reason to remove cannabis from the purview of the DEA and let research go forward, particularly concerning anti-cancer properties.

[Scuba]

5. If marijuana was discovered today it would be hailed as a miracle.

[thucythucy]

6. And patented, and sold only through prescription,

and advertised widely on TV.

"Ask your doctor about..."

[angel823]

9. this ^^^^^^

is the key.

Angel in Texas

[RainDog]

10. That's why former "Drug Czars" are lobbying for Sativex

They're trying to pretend it's anything other than whole plant cannabis that has been put into solvent and made into a spray...but that's what it is.

It's a less potent version of Rick Simpson's oil.

And it's currently legal for certain conditions (MS, PTSD, epilepsy, etc.) in Canada, GB, Germany, Spain and Israel.

Spain is the location of some of the most amazing research into the use of the CBD cannabinoids to shrink brain tumors. They've done one small test on humans whose cancers were beyond stopping and, even in those, CBD, applied to the site of the tumor, shrunk those tumors.