The cost to taxpayers of the FDA’s new anti-smokeless
tobacco campaign, dubbed The Real Cost, is $36 million. FDA Center for Tobacco Products Director
Mitch Zeller announced the campaign at the 8th National Summit on
Smokeless and Spit Tobacco, which was attended by a “coalition of
organizations, agencies and individuals committed to reducing and eventually
eliminating the use of smokeless and spit tobacco products.”
The zinger that Zeller focused on, however, was this: “Each
year in the U.S., more than 2,300 people are diagnosed with oral, esophageal
and pancreatic cancer due to smokeless tobacco use.”
I recently called on the CDC to release long-suppressed
smokeless tobacco data (here). The agency remains opaque on the matter, but Zeller
did offer that one hard number. Now we
must ask: Is it accurate?
Surprisingly, the only source reference for the figure is
found in the agency’s Tweet, here, which
points to a 558-page report by the National Cancer Institute and the CDC (here). The 2,300 figure, appearing on page 135, is
the result of a calculation by Jane Henley and Michael Thun, epidemiologists at
the CDC and the American Cancer Society.
They estimate that each year smokeless tobacco causes 1,601 oral
cancers, 184 esophageal cancers and 530 pancreatic cancers, totaling
2,315.
Drs. Henley and Thun estimated the number of current
smokeless users in the U.S., and then applied relative risks (RR) from American
studies of smokeless tobacco compiled by a 2008 article by Paolo Boffetta (here) – which I
previously showed to be a classic case of data cherry picking (here).
Henley
and Thun’s report of 700+ cases of esophageal and pancreatic cancers is
unsubstantiated, as Boffetta’s RRs for these diseases among American smokeless
users are not statistically significant.
Boffetta
reported an elevated RR of 2.6 (95% confidence interval = 1.3 – 5.2) for oral
cancer among American smokeless users, but his risk analysis used only six studies,
with no explanation of inclusion criteria.
The following table provides details about his results.
| Epidemiologic Studies Used by Boffetta for U.S. Summary Risk Estimate = 2.6 (1.3 – 5.2), Smokeless Tobacco and Oral Cancer (Lancet Oncology, 2008) | |||
|---|---|---|---|
| Source Study (Author, Journal Year) | Includes smokers | Product, Number of Cases in Users | Relative Risk (95% Confidence Interval) |
| Men | |||
| Mashberg, Cancer 1993 | Yes | Dip-Chew, 52 | 0.8 (0.4 – 1.9) Dip |
| 1.0 (0.7 – 1.4) Chew | |||
| Kabat, International Journal of Epidemiology 1994 | No | Chew, 4 | 2.3 (0.7 – 7.3) |
| Dip, 0 | 0 | ||
| Henley, Cancer Causes and Control 2005 | No | ST, 4 | 2.0 (0.5 – 7.7) CPS-I cohort |
| ST, 1 | 0.9 (0.1 – 6.7) CPS-II cohort | ||
| Women | |||
| Winn, New England Journal of Medicine 1981 | No | Dry Snuff, 79 | 4.2 (2.6 – 6.7) Whites |
| Dry Snuff, 12 | 1.5 (0.5 – 4.8) | ||
| Blot, Cancer Research 1988 | No | Dry Snuff, 6 | 6.2 (1.9 – 19.8) |
| Kabat, International Journal of Epidemiology 1994 | No | Chew, 0 | 0 |
| Men and Women Combined | |||
| Stockwell, Head and Neck Surgery 1986 | Yes | ST, Men, 1: Women, 0 | 2.3 (0.2 – 12.9) Tongue |
| ST, Men, 3; Women, 2 | 11.2 (4.1 – 30.7) Other Mouth | ||
| ST, smokeless tobacco unspecified | |||
| CPS I and II, American Cancer Society surveys | |||
Some of the studies referenced by Boffetta included smokers,
who are at much higher risk for oral cancer. Additionally, men who dipped
or chewed had no risk for oral cancer in any of the studies. Boffetta’s elevated risk estimate of 2.6 was
based almost entirely on women in the Winn and Blot studies. As I have
explained (here),
elevated oral cancer risk among women in those studies was due to use of
powdered dry snuff (here). The table clearly shows the difference in
risk between powdered dry snuff used by women and the dip/chew products used by
men. Boffetta’s estimate should never be
applied to men who dip and chew.
Unbiased epidemiologists would be appalled to learn that the
FDA is basing its smokeless campaign on population cancer estimates derived
from unreliable and inappropriate RRs.
Even if the FDA’s claim of 2,300 smokeless-related cancers was
accurate, the number would pale in comparison to the 480,000 U.S. deaths per year due to smoking.
To deal with The Real Cost of tobacco use, the FDA should
publish an honest estimate of the risks and consequences of smoking and
smokeless use, and issue public messages that inform rather than mislead. The current campaign wastes taxpayer
resources, obfuscates the truth about smokeless tobacco and, ultimately, denies
smokers information that could save their lives.
1 comment:
Brad - absolutely outstanding analysis that should put FDA/CTP to shame.
In a related development, Tobacco Control has now published my e-letter in response to the views of Matthew L. Myers, President of Campaign for Tobacco-Free Kids on what the FDA should be doing better:
e-letter - Missing the point
The fifth bullet relates to the FDA's function with respect to campaigns like this...
5. FDA suffers from mission creep - a regulator should not be involved in campaigning. FDA should function, and be seen to function, as a neutral technocratic regulatory agency, leaving the hype to public health bodies like the CDC. In this case, there is a further problem - the scientific foundations of the new smokeless campaign are very poor and undermine FDA's credibility more generally. FDA should stick to its core mission and do it better.
This sloppy use of data gives little confidence that FDA has the capability or the inclination to evaluate the Swedish Match MRTP application fairly and sees no problem with misleading the public unless a tobacco company intervenes to stop them... That is the subject of the fourth point in the letter.
4. FDA applies a bizarre approach to communicating the far lower risk of products like snus to consumers. This starts with a default FDA-imposed warning that is technically correct but not truthful because it is highly misleading ("this product is not a safe alternative to smoking"). It then requires tobacco companies to calculate if they are rich enough, the data extensive enough and whether it is sufficiently in their commercial interest to go through an arduous process to convince the FDA to allow them to change the warning to something more truthful ("No tobacco product is safe, but this product presents substantially lower risks to health than cigarettes") - and face hostile resistance from tobacco control campaigners such as the author. FDA and CDC should be assessing the relative risks of these products, and communicating them clearly - so that public risk perceptions become, as far as possible, aligned with scientific reality.
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