Dependence Level Higher with Cigarettes Than with Smokeless Tobacco

As noted previously (here), Drs. Karl Fagerström and Tom Eissenberg have described a continuum of dependence among tobacco and nicotine products.  They concluded that cigarettes are the most dependence-producing (addictive) product and that smokeless tobacco is intermediate, evidenced by clinical trials showing that quitting cigarette smoking is more difficult than quitting ST.

In a new study published in Nicotine & Tobacco Research (abstract here), I use data from the 2003 Tobacco Use Supplement of the Current Population Survey to directly compare time to first use (TTFU) among smokers and smokeless tobacco users in a nationally representative sample.  My collaborators in the work are Nantaporn Plurphanswat, research economist at University of Louisville’s Brown Cancer Center, and Karl Fagerström.

Time to the first cigarette (TTFC) after waking up in the morning is a well-established measure of dependence among smokers – the shorter the TTFC, the stronger the addiction.  This measure is the key component of a scale developed in the late 1970s by Dr. Fagerström, for whom the scale is named.  TTFC is strongly correlated with abstinence and time to relapse among smokers enrolled in cessation trials and in nationally representative samples of smokers from four countries.  A comparable measure has been developed for smokeless tobacco use.

We examined TTFU among 10,500 white men who were daily cigarette smokers and 1,200 who were daily smokeless tobacco users.  Smokers were classified according to number of cigarettes per day (cpd) smoked: light (1-14 cpd), moderate (15-24 cpd) and heavy (25+).  Smokeless tobacco users were subgrouped as exclusive users or former smokers.

The results show that dependence among smokeless tobacco users is similar to that among light smokers (1-14 cpd), 9% of whose TTFU was less than 5 minutes, and 23% under 30 minutes.  Differences in TTFU between smokers and smokeless tobacco users can be seen in the chart below, which is from our study.

Our findings support the Fagerström-Eissenberg hypothesis that the dependence level of cigarettes is generally higher than that of smokeless tobacco.  This has positive implications for tobacco harm reduction, which is the substitution of smoke-free tobacco products for cigarettes among smokers unwilling or unable to quit.  Switching from smoking to smokeless tobacco use is associated with a huge reduction in health risks.  This study adds evidence that a switch to smokeless tobacco might also increase the chances for becoming completely tobacco-free.

Colorado State Smoking Ban: No Impact on Heart Attacks

As early as 2004, various medical journals published articles claiming that small-community smoking bans resulted in nearly immediate reductions in heart disease.  For example, the high-profile BMJ reported that hospital admissions for acute myocardial infarction (AMI) declined 40%, from 40 to 24, in Helena, Montana, after implementation of a smoke-free ordinance (here).  Circulation, the journal of the American Heart Association, reported that AMI admissions dropped 27% “within months” in Pueblo, Colorado (here). Similar reports came from Bowling Green, Ohio (here), Monroe County, Indiana (here) and beyond. 

The striking implication was: Eliminating second-hand smoke saves lives by reducing heart disease.

There were two problems with these claims.  First, the declines, based on small numbers of observations, were actually consistent with random variation (here).  Second, none of the reports accounted for the long-term downward trend in heart disease in the U.S.; they credited no-smoking intervention with the lower number of AMIs at a time when rates were declining nationwide.

In 2011, I documented that state-wide smoking bans in California, Utah, Delaware, South Dakota, New York and Florida had little or no immediate measurable effect on AMI deaths. The study, published in the Journal of Community Health (here), eliminated the “tiny-number” problem and factored in the national downward trend in AMI deaths.

I discussed these findings in my blog (here), but the work was largely ignored, until now.

Recently, researchers from three Colorado institutions reported AMI rates before and after a statewide smoking ban there; their work appears in the American Journal of Medicine (here).  (Thanks to Chris Snowdon, who also blogged about it here).

Paul Basel and colleagues found that “No significant reduction in [AMI] rates was observed” after the Colorado ban was implemented.  They also referred to our study:

“[The Rodu et al.] study compared the decline in [AMI] mortality in 6 states with smoke-free ordinances, with the average decline among 44 states unaffected by smoke-free policy.  No state with a smoke-free ordinance had a significantly lower observed [AMI] mortality compared with that expected by the nationwide secular decrease in states without the ordinance.  This emerging evidence highlights the importance of accounting for secular trends in [AMI] incidence before definitive attribution to smoke-free ordinances can be made.” 

It is comforting to see unfounded second-hand smoke claims corrected, particularly in the pages of a prestigious journal.

Gateway Claims Aimed at E-Cigarettes: Counterfeit, Déjà Vu

In their war against e-cigarettes, government officials often claim that the devices are a gateway to smoking.  CDC director Dr. Tom Frieden asserted (here) that “…many kids are starting out with e-cigarettes and then going on to smoke conventional cigarettes.”  The National Cancer Institute last March promoted (here) Dr. Stanton Glantz’s tortured analysis of youth e-cigarette use (discussed here and here).  While his data failed to support a gateway effect, his employer, the University of California San Francisco, made the claim anyway (here).     

Politicians also have a penchant for yelling “fire” about smoke-free devices.  U.S. Senator Richard Durbin and Democratic colleagues in the House and Senate issued a report in April titled “Gateway to Addiction” (here).  The term “gateway”, obviously used as an attention-grabber on the cover, appeared only once in the text -- as a nonspecific example of how e-cigarettes “could also increase public health risks” for non-smokers.

The marijuana gateway claim didn’t gain currency until the 1950s.  Back in the 1930s, Harry Anslinger, the first commissioner of the Federal Bureau of Narcotics (here) and the driving force behind the prohibitive Marijuana Tax Act of 1937, denied a gateway claim during Congressional hearings.  According to the excellent history of marijuana prohibition by Richard Bonnie and Charles Whitebread (here), Representative John Dingell asked Anslinger “whether the marihuana addict graduates into a heroin, an opium or cocaine user.”  The Commissioner replied unequivocally, “No sir; I have not heard of a case of that kind. I think it is an entirely different class. The marihuana addict does not go in that direction.”

By 1951, Anslinger changed course while testifying in favor of the Boggs Act, which increased federal penalties for narcotics and marijuana.  Endorsing marijuana’s new reputation as a treacherous gateway drug, he said: “The danger is this: Over 50 percent of those young addicts started on marijuana smoking. They started there and graduated to heroin; they took the needle when the thrill of marijuana was gone.”

So began marijuana gateway scaremongering, which Dr. James Anthony, professor of epidemiology and biostatistics at Michigan State, labels as “…‘vapors’ that emerged from a political cauldron during the middle of the 20th century when it was very difficult to find definitive and convincing evidence of harmful effects of cannabis use – over and above (1) the sometimes extremely severe consequences of criminal penalties for simple cannabis possession and use, and (2) adverse effects on mouth, nose, throat, and lung.” (abstract here)   

This should sound strikingly familiar to vapers (e-cigarette users) and tobacco harm reduction advocates.  As they did with marijuana, prohibitionists make the gateway claim against e-cigarettes in the near-total absence of “definitive and convincing evidence” of harm.