Thursday, April 3, 2008

Safe to Smoke? Bull$h!*

I am so pissed off this morning. Mainly because of the assault that must be led by Phillip Morris, DeCode and the Devil Himself.

In a recent press push.....from as far as I can see. There is now a "magic bullet" for smoking and avoiding cancer. Recently published data in the Journal Nature is being over hyped. From Good Morning America to Fox News to MSNBC to my friend Hsien at Eye on DNA (Well hers isn't so much hype)

From Her blog

All three studies identified regions on chromsome 15 that are associated with nicotine dependence, lung cancer, and peripheral artery disease. The deCODE study focused on SNP rs1051730 located on chromosome 15q24 in the CHRNA3 nicotine acetylcholine receptor. People with one copy of the “T” version of this SNP had:

30% increase in risk of lung cancer OR of 1.3
20% increase in risk of peripheral artery disease OR of 1.2

Half of people of European descent have at least one copy of the higher risk SNP and 10% may have two copies which increases their cancer risk by 80%...... OR of 1.8

From the Nature Report
Tobacco is thought to be responsible for about 5 million premature deaths every year and smoking is still clearly the largest risk factor. But the new results suggest that, amongst smokers, some people may be as much as 80% more at risk than others thanks to their genes.

A solid analysis...but there are some old statistics out there that you need to know...
First, in the quoted 80% study the Odds Ratio of cancer in Homozygotes was 1.8. OR of 1.8 equals an increased risk of 80%.....That is small potatoes. Why? See here.

Well, In an environmental analysis in 1990 it was found that children exposed to Household exposure to 25 or more smoker-years during childhood and adolescence doubled the risk of lung cancer an odds ratio of 2.07. Obviously genotype was not evaluated.

So why is this group of smokers likely to quit if they even won't quit to prevent their children from getting cancer? Just chalk it up to the genes!

So what is the risk of cancer for smokers? You should go to the NCI website and see for yourself.

Is this a worth while genetic test? No. The risk of head and neck cancer, something smokers get too is skyrocketed in the face of family history or alcohol consumption. If you think 80% is high, try 4200%....... naive reporters (Except for you Amy, sorry to bash your colleagues) To predict lung cancer risk more accurately, try the M.D.Anderson Model.

Why is this study and the press surrounding it silly and misleading? Because smoking causes more than just lung cancer......The study should have included all that case you would have found much more interesting results...

The Sherpa Says:
Bottom Line, if deCode comes out and markets this test they should be shot. If they do sell it, it is only a sign of how absolutely horrible the financial position they are in. Smokers don't need further encouragement to keep smoking.....It is hazardous to them and the ones they love. Just quit....most people can't stand your smoke or paying for your cancers.... Here's to NY!


Sciphu said...

I'm sure you are right to lash out against the press-coverage, but the studies themselves are the best ever examples of gene-environment interactions. I for one hope to see lots more studies like this. I am also confident that such a test would be very useful to convince smokers to quit, and I strongly doubt that smokers who test negative for this (these) SNP(s) are less inclined to quit. Smokers know they are taking high risks anyway, increasing this risk even more may help some of them realize that the odds are unbeatable. Go ahead and sell the test I say.

Hercules said...

Well a while back OGG1 was the culprit, then SLC6A3 with DRD2 thrown in for good measure - and now it's all down to CHRNA3 ... I think it will be while before they really find the "smoking" gun?

Steve Murphy MD said...

I don't mean to snap. I just don't want people to have an excuse for smoking. I feel the press coverage gives a false sense of protection to least with the coverage I have read....I don't hate the press. I admire them...but this is a more nuanced topic.

Anonymous said...

From the press reports, deCODE don't even claim the variants up cancer risk independent of smoking (the other group which has published does). deCODEme already tests for the relevant SNPs, and I expect that if I were a customer, I'd want to be able to check my results. I would not want them suppressed because some lefty twat with competing business interests doesn't like deCODE.

Steve Murphy MD said...

"I would not want them suppressed because some lefty twat with competing business interests doesn't like deCODE."

This blog has no attachment to my business therefore I will not comment on such here. Please feel free to call me 914.954.6406 to discuss

As for your the "lefty" comment....How can one who has never broken bread with me ever know my political affiliation? I take offense to the term twat sir/maam. If you wish to have the meaning of your results discussed please feel free to seek out skilled professionals.


Anonymous said...

Hyperventilating about cigarette smokers = pretty good indication you are of the left. (And I say this as someone who has never smoked and is not particularly fond of others' smoking.)

If you're going to try to twist this story to make deCODE out as villains who "should be shot", I'd say you have a responsibility to disclose any possible conflicts of interest, regardless of whether "this blog has any attachment to" your business.

Alberto said...

I would rationaly completely diasagree but what about setting up a trial of 1000 smokers... make them take this test and see how many stop smoking, and if others smoke more. It seems nonsense but maybe it could be more effective than terrorist campains such as "you will die of cancer, smoker!". People need geeky things. And if you tell them you have an 80% increased risk - that "80" seems a HUGE number...

Steve Murphy MD said...

What if you were predisposed to cancer and know that 2nd hand smoke can increase your risk? Does that make you the arch enemy of Ann Coulter or Sean Hannity?

I am not mixing business with my personal blog now....It is true, I do have a medical genetics practice that is NOT in direct competition with lab testing. So stop being a chuckle head.


Steve Murphy MD said...

Alberto see:

1: Ann Behav Med. 2007 Feb;33(1):22-8.

Testing affected smoking cessation of those who were afflicted with the alpha 1 AT deficiency, but not those who were merely carriers.


Anonymous said...

you mention or market your business in a large percentage of your posts, claiming that this blog has no attachment to it is ridiculous.

D.Alexander said...

Low Level Cadmium Exposure Linked To Lung Disease...Science Daily reported on August 20 that new research suggests that cadmium is one of the critical ingredients causing emphysema, and even low-level exposure attained through second-hand smoke and other means may also increase the chance of developing lung disease.