05 March 2011

Unhealthful News 64 - Four tales of bad research on tobacco

There are far too many examples of bad research and reporting on tobacco to cover (think terrible methodology, over-conclusion from weak studies, and biased analysis or other bad behavior by researchers).  But it is worth covering some of them.  Rather than spend too many days on them, though, I will cover four in one day.  The two that relate directly to THR are over at the TobaccoHarmReduction.org blog, and the other two are here.

The first one is ostensibly about smokeless tobacco, but is about the news and products that are not part of THR, so I put it here.  As frustrating as the muddled discussion about smokeless tobacco products is in the West, it is even more of a mess in India despite the fact that there are more users of plant-based dip products there than in the entire West.  The muddle starts with the fact that products are often mis-identified as being smokeless tobacco even when they are not predominantly tobacco, or even tobacco at all.  Then there is the epidemiology:  It is widely believed that the Indian products cause a substantial risk for oral cancer, unlike American or Swedish style products, though this is based primarily on the ecological data, the high overall incidence of oral cancer in the population coupled with the great popularity of the products.  The epidemiologic studies, on the other hand, are almost all such a muddle that it is impossible to make any sense of them.

The popular press discussion is just as bad, like this Times of India article about the recent ban on plastic packaging for the little pouches (of a size that can be used in one go, though perhaps often split up) in which the products are typically sold in.  These cost in the order of one or two cents each (in Western currencies) and so it is an affordable way to create a huge number of pieces of non-degrading litter.  This is part of the motivation for the ban, though if manufacturers switch to foil instead of paper packages, nothing will be accomplished.  But it gets worse.  The only downside noted about the resulting increase in cost is the impact on the industry, not the much larger impact on consumers of the estimated 50% increase in cost.  This is  a fundamental lack of understanding about economics, since in competitive markets, sales taxes -- and, equivalently, mandatory increases in manufacturing costs -- are paid almost entirely by the consumer, and not much by the producers, except to the extent that the price increase shrinks the market.  Though I suppose it might just reflect the fact that the gulf between the elites (the producers who lose a little bit, and the newspaper) and the poor people (the consumers of these products) is so enormous that the newspaper readers actually do not care about consumers.

That last observation is consistent with what was said when the nanny state motivation enters:
"It is good for consumers, at least they will consume less. It is good for the pocket as you buy less of these harmful products," says Ravi Prakash, a university student, who could not quit chewing tobacco despite repeated efforts.
Meanwhile, anti-tobacco organisations were happy with the ban.
"The ban on plastic sachets is a good initiative. It would help in maintaining ecological balance and when these products will become costly, obviously it will be out of the reach of common people," environmentalist S Awasthi said.
Yes, that was really all run together like that; I did not cut out any words.  So apparently the motivation is that this is like raising taxes, though much less efficient (taxes are a transfer, with no real resource loss while this actually burns through real resources) and the price increase will cause people to quit rather than just hurting the poorest in a poor society who continue to indulge in these products.  After all, as any good "environmentalist" knows, it is good to put things "out of the reach of the common people".  Why do we have a feeling that the success of this policy will inspire the elites in the West to make more effort to keep our low-risk actual tobacco products out of the reach of the common people?

The next example, in Neuropsychopharmacology compared 25 smokers, ages 15 to 21, to 25 nonsmokers.  This few may be enough to show that brain scans come out differently between the two groups sometimes, though it appears they had to fish for results with this one.  The study consisted of scanning their brains when they did a respond-to-the-blinking-light type task.  Apparently the authors did not detect much difference between the two groups, but claimed:
...the Heaviness of Smoking Index, a measure of smoking behavior and dependence, was negatively related to neural function in cortical regions of the smokers. These findings suggest that smoking can modulate prefrontal cortical function. Given the late development of the prefrontal cortex, which continues through adolescence, it is possible that smoking may influence the trajectory of brain development during this critical developmental period.
In other words, they are reporting that there was a difference between the heavy or more dependent smokers compared to the nonsmokers or the more casual smokers.  From this they concluded that the smoking was causing brain changes.  This is certainly possible, but I seem to recall that the conventional wisdom about smoking and playing blinky light games is that, yes, there is a difference and it can help explain why some people become dedicated smokers while others dislike it or can take it or leave it.  The thinking was that the games indicated smokers had less good brain functioning in some specific ways and that smoking was so beneficial to them because it helped overcome those deficits.  At least that was the conventional wisdom before the anti-tobacco/nicotine extremists got so much power that they could punish people who dared suggest there was something good about smoking.

Whether this is still believed or not, it should be obvious that confounding, perhaps in the form of causation in the other direction, is a possible explanation for the entire result.  That is, whatever caused the brain scans to look different could easily be the cause of, or another symptom of, whatever it is about the heavy smokers' brains that makes them get more benefit from smoking than those who choose to smoke less or none.  It never ceases to amaze me that people cannot figure out the difference between situations where a randomized trial, where an exposure was assigned, could not tell us much beyond what the observational research has already shown (a theme I have written much about), and situations where the confounding or possibility of causation in the "wrong" direction is so great that we actually do know very little without a controlled experiment.  It is not really that difficult.

Given that there is absolutely no way to do more than guess that the observed association was causal, the authors have no business stating the conclusion they did in the paper itself.  But they went further, with the worst kind of lying to the press, when they touted result in a press release as "Tobacco smoking impacts teens' brains, UCLA study shows".

Yes, this bit of junk science was from the University of California – surprise!  Funny, thing, though:  There was silence from the usual suspects, like those at University of California, who have made unethical attacks on researchers for doing legitimate research that happened to be funded by tobacco companies and those who had attacked the lead author of this study for her previous work.  Oh, did I not mention that the study was funded by a grant from Philip Morris?  Well, why would I, since the study stands or falls on its merits (it falls).  But what also falls is any shred of remaining integrity that the anti-tobacco-funding people might have:  We searched and could not find any hint of criticism of this study as being evil because of the funding.  Gee, could it be that those people only use rhetoric about funding as an excuse to pretend away results they do not like?  Might they actually be actively aware that their whole ad hominem tactic is just a political game, and so know that it does not affect the science when they do like the result?  Hmm.

For the other two examples, please follow the link at the beginning. 

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