FDA and CDC Generate Smokeless Scaremongering

While the FDA and CDC refuse to acknowledge that smokeless tobacco causes almost no disease, agency staff have produced a fresh study (abstract here) showing that smokeless tobacco users have higher trace levels of nicotine and some contaminants than do smokers.  This meaningless finding (explained below) leads to grossly misleading headlines, such as “Smokeless Tobacco More Toxic Than Cigarettes, Study Says” from Time’s Alexandra Sifferlin. (Other recent tabloidish stories from this reporter include “Flavor Science Explains How You Can Hear the Way Your Food Tastes,” “I Tried It: A 6 am No-Booze Dance Party on a Boat,” and “Healthiest Halloween Candy”).   

The media was served up a juicy quote from the FDA’s Brian Rostron, the study’s first author, in a press release (here): “exposure to nicotine and the cancer-causing tobacco constituent NNK were higher among exclusive smokeless tobacco users than exclusive cigarette smokers. This continues to put smokeless tobacco users at risk for adverse health effects, including cancer.”

First, nicotine is not a toxin, and it doesn’t cause any “adverse health effects, including cancer.”  

Second, while the study found higher levels of NNK among smokeless users than smokers, that does not support the claim that “smokeless tobacco users [are] at risk for adverse health effects, including cancer.”  Decades of epidemiologic studies involving millions of Americans show that smokeless tobacco users’ risks are infinitesimal.  British researchers estimate that U.S. smokeless-related cancer deaths are zero.

Third, from 1999 to 2012, the period of the study, trace levels of NNK dropped by two-thirds in smokeless tobacco users.

And finally, the results show that smokeless tobacco users had lower levels of mercury (in their blood) and arsenic (in their urine) than nonusers of tobacco.  In fact, smokers also had lower levels of these metals.  The study authors did not discuss the health implications of these findings.       

Public health officials should focus on meaningful research and provide appropriate scientific context for their findings, rather than scaremonger via the media and deter smokers from transitioning to markedly less harmful smoke-free products.

Stroke Risk Same for Menthol and Nonmenthol Smokers

Dr. Nicholas Vozoris in 2012 reported that “…smokers of mentholated cigarettes, and in particular women and non–African Americans, have significantly increased odds of stroke compared with nonmentholated cigarette smokers.”  (reference here).  He used National Health and Nutrition Examination Surveys (NHANES) data to calculate odds ratios of 2.3 for all menthol smokers, 3.3 for women and 3.5 for non-African Americans.  Dr. Vozoris found no increased risk for hypertension, heart attack, congestive heart failure or emphysema among menthol smokers. 

If the Vozoris findings on menthol and stroke were independently confirmed, they could serve as a basis for a ban on menthol cigarettes.  Instead, an analysis of NHANES data by Dr. Brian Rostron (here) comes to an entirely different conclusion.

Dr. Rostron found that African-American menthol smokers had a significantly lower risk for stroke (OR = 0.52, 95% confidence interval= 0.28 – 0.99) than nonmenthol smokers.

“It is not clear to me,” Dr. Rostron writes, “how Vozoris obtained his findings, given that I cannot replicate his general results for stroke using the NHANES data and analyses that he specified.  Moreover, the absence of observed differences in stroke prevalence among NHANES menthol smokers would suggest that methodological or analytical issues may have affected his results.”

Dr. Rostron earlier showed that menthol smokers have lower lung cancer risks than nonmenthol smokers (here).

Promoted by the Archives of Internal Medicine (here), the Vozoris study was covered by major news media (here  and here).  The journal, which changed its name to JAMA Internal Medicine in January 2013, is not publicizing the study that corrects the deficient 2012 analysis.

Although medical journals cannot avoid publishing erroneous reports, editors should take all measures to correct the types of mistakes discovered by Rostron.

Finally, U.S. Official Admits that Smoking Deaths are Declining

Dr. Phil Cole and I asserted in 2008 that smoking-related deaths in the U.S were on the decline. Finally, this month, an FDA official arrived at the same conclusion in a journal article.

In “Calculating the Big Kill,” which appeared in Regulation, the Cato Institute’s flagship publication (here), I made the case that “CDC [Centers for Disease Control and Prevention] estimates of smoking-related deaths do not add up.”  I noted that “U.S. smoking rates have been declining almost continuously since the mid-1960s, when 42 percent of American adults smoked.  The rate dropped to 28 percent in 1988 and has now declined to 21 percent.  Put simply, the proportion of Americans who smoke has been cut in half over the past 40 years.”

I asked, “Why have the CDC [big-kill] estimates not fallen?”

My question was based on a research study that Dr. Cole and I published a year earlier in Nicotine and Tobacco Research (abstract here), showing that “there were 402,000 deaths attributable to smoking in 1987 and 322,000 in 2002.”  We noted that despite the substantial decline in smoking prevalence, the estimate of smoking-attributable deaths from the Centers for Disease Control and Prevention had changed hardly at all. 

Five years later, my question is still relevant.  The answer is clear: The CDC chose not to acknowledge the fact that deaths had plummeted.

Brian Rostron, a scientist at the FDA, has now published a study, also in Nicotine and Tobacco Research (abstract here), demonstrating that smoking-attributable deaths declined from 398,000 in 2000 to 370,000 in 2007.

As I explained in my Cato article, most people mistakenly believe that CDC officials actually count the number of smokers who die each year.  The truth is that the CDC uses a model that estimates the number of current and former smokers based upon data in the National Health Interview Survey (NHIS); the CDC subjects those smoker estimates to relative risks developed by the American Cancer Society in the 1980s, and then produces an estimate of the number of deaths that would not have occurred if they had never smoked.  Like any model, the quality of the output is dependent on the quality of the input.

I had noted that the CDC was using 20-year-old data to produce its “big-kill” estimates; Dr. Rostron concurs, saying that “the CDC has not substantially revised the methodology or data that are used in this procedure since their introduction in the 1980s.” 

Rather than using decades-old risk estimates, Dr. Rostron updated the relative risks for smokers and former smokers by calculating them from NHIS subjects from 1997 to 2004 who were followed through 2006 with linkage to the National Death Index.  Unlike the outdated CDC estimates, he adjusted risks for age, race/ethnicity, education, alcohol consumption and body mass index, which are important confounding factors for some or all smoking-related diseases.

Here are Dr. Rostron’s big-kill estimates:

Smoking-Attributable Deaths Among Men and Women in the U.S., 2000, 2004 and 2007
Year	Men	Women	All
2000	211,000	187,000	398,000
2004	200,000	180,000	380,000
2007	195,000	175,000	370,000

Although declining, Dr. Rostron’s big-kill numbers may still be too high because of the way he estimated deaths among former smokers.  Using his model, former smokers accounted for about 177,000 out of the 370,000 deaths from smoking in 2007.  This seems to be excessively high, as the 2007 NHIS documents that 60% of the 39 million former smokers had quit over 15 years previously.  Any excess risk for a smoking-attributable death was minimal to nonexistent in this group. 

Dr. Rostron’s deaths among former smokers were likely concentrated in those who quit less than 5 years earlier, and who therefore have risks similar to those of current smokers.  But it is inconceivable that this group of 6.3 million former smokers produced almost as many deaths as the 27.5 million current smokers in 2007.  Dr. Rostron’s model should be revised to reflect the different risks among former smokers who have short or long quitting histories.

Regardless, the main message of this study is valid: Smoking-attributable deaths have been in decline for over a decade.  This is good news that the CDC and other federal agencies have ignored for far too many years.