The correlation of smoking and disease progression

Thomas · Post by **Thomas** » Fri Jul 18, 2008 12:17 pm

There's a new study just released claiming "Smoking worsens the prognosis in multiple sclerosis". I don't see how they can conclude that smoking worsens MS from this study. (correlation does not imply causation etc.). Any thoughts?

cheerleader · Post by **cheerleader** » Fri Jul 18, 2008 1:07 pm

Hi Thomas-
The Swedish study you've linked to states that early smoking habits double the risk of someone with MS developing a progressive form. Late onset tripled the risk. It's a small study, and because this is only an abstract, we don't see all the figures the docs used to come to this conclusion. However, it makes sense to me. Some docs believe a component of MS is vascular disease. Nicotine causes blood vessel constriction- and increases the toxin load in the body.

"Nicotine, which mimics the affects of acetylcholine, acts primarily on the autonomic nervous system. In a dose of less than 50 mg, it can cause respiratory failure and general paralysis. Smaller toxic doses can cause heart palpitations, lowered blood pressure, nausea, and dizziness. A person who smokes inhales approximately 3 mg from one cigarette. This amount increases the heart rate, constricts the blood vessels, and acts on the central nervous system, imparting a feeling of alertness and well-being. Although not considered carcinogenic, nicotine probably contributes to the increased incidence of heart disease seen in smokers and may enhance the growth of tumors caused by carcinogens."
http://encyclopedia2.thefreedictionary.com/Nicotene

None of the effects of nicotine are good for someone with MS. It appears, from this study, that early smoking is linked to progressive disease.

AC

Thomas · Post by **Thomas** » Fri Jul 18, 2008 2:21 pm

Hi cheerleader,

Sure smoking is not healthy, but I still think it's strange to come to this conclusion based on self-reported smoking habits.....

cheerleader · Post by **cheerleader** » Fri Jul 18, 2008 3:13 pm

After a quick googling, it appears the Dept. of Neurology at Umea and the Karolinski Institute are doing alot of studies on the affects of smoking on the brain...Alzheimer's, Parkinsons, MS, even migraines. I don't see why self-reported smoking habits would be strange in this situation...they simply asked if folks with MS if they smoked and when they started. Probably an adjunct to another study they were doing.

Nicotine affects the vascular system and the brain in many different situations. Sweden doesn't have much of a tobacco industry, so they are not afraid of finding new ways smoking can harm folks.

AC

Post by **jimmylegs** » Fri Jul 18, 2008 4:44 pm

the abstract is released ahead of print. this article is not included in issue 14(6): 719-861. when it is made available i should have full text access, if anyone is interested.

Thomas · Post by **Thomas** » Sat Jul 19, 2008 4:38 am

cheerleader wrote: I don't see why self-reported smoking habits would be strange in this situation...they simply asked if folks with MS if they smoked and when they started.

The problem is that when you have two observations, in this case smoking habits and disease progression, you can't say that one the causes the other. What they found was a co-relation between smoking and disease progression, and they just seem to assume, on basis of known effects of smoking, that the one (smokng) causes the other (disease progression). Correlation does not imply causation.

CureOrBust · Post by **CureOrBust** » Sat Jul 19, 2008 6:02 am

cheerleader wrote:...alot of studies on the affects of smoking on the brain...Alzheimer's, Parkinsons, MS, even migraines.

The problem with the internet is that it has an opposite opinion for every one you are looking for (if you look for it). Many reports say that nicotine may help with Alzheimer's & Parkinsons.

http://www.forces.org/evidence/hamilton ... cotine.htm

http://media.www.vermontcynic.com/media ... age2.shtml

http://www.cnn.com/HEALTH/9610/22/nfm/a ... index.html

Personally I have never smoked, and would not start or recommend anyone to.

gibbledygook · Post by **gibbledygook** » Sat Jul 19, 2008 6:14 am

Whenever I have a puff on a tobacco joint it has a disastrous effect on my bad right leg motor function. Tobacco is totally poisonous to my central nervous system.

Lyon · Post by **Lyon** » Sat Jul 19, 2008 6:33 am

cheerleader · Post by **cheerleader** » Sat Jul 19, 2008 7:05 am

Thomas, you're right...correlation does not imply causation. All they are saying is- just like age at onset of MS, - it appears early smoking is linked to a progressive disease course. JL, I think we'll need the full study when you can get it.

Not to be a total cynic, but all of the studies which conclude nicotine helps the brain were done in America and England...two countries where the tobacco industry often sponsors such "studies" and the industry is thriving. One study was even partially funded by Phillip Morris Co.

Sweden is now part of the EU antismoking project, spending millions of euros on ads and seeking to ban smoking in many public places. They also are pushing their own smokeless tobacco...."snus."

You're right , Cure, you can find just about anything on the internets!
AC

Lyon · Post by **Lyon** » Sat Jul 19, 2008 7:19 am

Thomas · Post by **Thomas** » Sat Jul 19, 2008 7:53 am

cheerleader wrote:All they are saying is- just like age at onset of MS, - it appears early smoking is linked to a progressive disease course.

Ah but they're not only saying there's a link, they're saying that this link is causal: "Smoking worsens the prognosis in multiple sclerosis." Not much room for correlation in that statement. Had they said something like "we've found a link between smoking and disease progression but we don't really know if it's causal or coincidental" they would have had no argument from me.

cheerleader wrote:Sweden is now part of the EU antismoking project, spending millions of euros on ads and seeking to ban smoking in many public places. They also are pushing their own smokeless tobacco...."snus."

Aha! It's a conspiracy to get us all using snus instead of cigarettes! I knew there was a hidden agenda with this "study".