Thursday, December 12, 2024

Up in Smoke: The American Heart Association on Smokeless Tobacco

 

The American Heart Association published a policy statement in its journal Circulation, titled, “Impact of Smokeless Oral Nicotine Products on Cardiovascular Disease.” (here)  Below, I cite with permission excerpts from a review by Clive Bates, along with my comments.

The smokeless tobacco [ST] policy statement from the American Heart Association is too long to review in depth, but my main take outs are:

1. It’s a modest improvement on what came before and it has factually correct things in it, but it does not work as a basis for policymaking or risk communication.

Clive notes the biggest problem, the conclusion is preordained: “summarize implications of use for [the AHA’s] policy work toward ending tobacco and nicotine addiction in the United States.

So if your goal is a nicotine free society, no level of risk will ever be tolerable, and your search for harms (real, exaggerated or imaginary) will be driven by the need to support this conclusion.  We do not have this “elimination” philosophy with other common recreational drugs - caffeine, alcohol and cannabis, even though these are not risk-free.  We take the approach of managing risks to levels acceptable in society. AHA should also know by now that regulation and risk communication in this field is plagued by unintended consequences - adverse behaviour change (more smoking), illicit trade and risky workarounds - and these consequences can be more severely negative than the intended benefits.

Let me be clear - I am not recommending tobacco or nicotine use to anyone… this is better understood as a phenomenon in society driven primarily by its perceived or real benefits to users - it makes people feel better and feel as though they function better. No space was available in the paper to discuss this important aspect of nicotine use - why people use it. The demand for nicotine is not going to disappear and the availability of nicotine in much safer forms than smoking removes nearly all of the main deterrent for nicotine use - extreme harmfulness over the long term of inhalation of smoke. I suspect there would be a very different attitude to ST if the public had not been confused by years of deceptive risk communications [only 13.4% think ST can be safer than cigarettes - HINTS 2017]. There are no upfront statements that address this risk miscommunication.

2. No clarity on the place of ST on the nicotine risk continuum.

This is the only mention of ST in the AHA statement: “Although there are no safe tobacco products, a continuum of risk across tobacco and oral nicotine products exists, with the greatest risk associated with combustible products such as cigarettes and cigars.” 

Everyone agrees that there is no “safe” tobacco product, and that combustion and smoke produce the greatest risk, but it is unacceptable to ignore decades of evidence proving that ST is only about 2% as risky as smoking.

3. Nothing to correct huge false risk perceptions and more to add to them.

While many studies have found that ST use confers minimal to no increased risk for cardiovascular diseases, the AHA cherry-picked research that portrays ST badly and they ignored, or were ignorant of, those studies’ major flaws.  For example, the AHA cited a seriously defective 2014 Swedish study in Circulation showing increased deaths among snus users with heart attacks (here).  Using that study’s results, my colleague and I found that continuing snus users actually had a lower death rate than those who used neither snus nor cigarettes (here).  Our analysis was so persuasive that the journal published it for the record (here).

Every ST prohibition screed includes a section on oral cancer, and this report, ostensibly about cardiovascular disease, adheres to the formula by quoting an infamous 2016 study by Wyss and colleagues that claimed a positive association of ST use and oral cancer.  Still, in a rare nod to truth and clarity, the AHA authors opine:

“It is noteworthy that many meta-analyses included individuals who reported use of high-nitrosamine ST products from many years in the past. These differences need to be considered carefully when extrapolating to oral cancer effects among individuals reporting use of currently available products with lower nitrosamine levels.”

Kudos, because that is what I have been documenting since 1994.  Wyss revealed that American men had zero excess mouth cancers associated with [low-nitrosamine] dipping or chewing tobacco (Odds Ratio, OR = 0.9), while women, who mainly use[d] [high-nitrosamine] powdered dry snuff, had a 9-fold elevated risk (here).

4. Detailing the mechanisms behind minor risks in a way that conveys greater risk than exists.

Almost every study showing some sort of material risk has been open to confounding or other methodological weaknesses - the high level mortality data show no excess risk for exclusive smokeless use in the US.

The AHA studiously ignores published research that failed to show excess risk from ST use; the FDA took a similar tack in an internal report last year (here). 

5. Not presenting a simplistic approach to nicotine use, and why people use it.

The AHA dwells on nicotine chemistry, toxicity, pharmacology and physiology, but in the end, they focus on the harm of nicotine addiction.  In doing so, they ignore the fact that hundreds of millions of people worldwide consume combustible tobacco and nicotine products, despite the long-term increased risk of dying prematurely from a plethora of diseases that could easily be avoided.

6. Disregards interactions between different forms of tobacco use with radically differing risks.

The AHA repeatedly mentions dual use as a negative side effect of ST, yet the association perpetuates dual use by ignoring or downplaying the well-documented differential risks between smoke and smoke-free tobacco.  This has been going on for decades; in 1991, the CDC reported that at least 23% of ST users also smoked (here).  Imagine how many dual users’ lives would have been extended if health professionals had been honest about the risk differential.    

7. A naive policy platform based on weak evidence of impact and blind to unintended consequences.

This review does have some useful though equivocating text buried within it as the truth is essentially undeniable.

Nicotine is the proximate cause of all tobacco-induced disease because it drives dependence and compulsive use. However, most of the harm from tobacco use results from inhalation of tobacco combustion products, which delivers high levels of oxidizing chemicals, numerous toxic volatile organic compounds, and carbon monoxide. Because oral nicotine products do not expose users to combustion toxins, an important question is the intrinsic toxicity of nicotine.

No, the real question is about the magnitude of risk - how this compares with smoking and how it looks in absolute terms compared to other risks that are routinely tolerated in society. It should also draw attention to the likelihood that ST use is likely safer than vaping, as there is no lung exposure and no thermal processes -just because something contains tobacco doesn’t make it more harmful than something that doesn’t.

Sadly, if predictably, there are no clear statements in this policy statement that aim to reset the public, medical or political misunderstanding of relative risk.  Even on cardiovascular risk there are statements that suggest minimal risk in the American context, but buried deep within

The policy proposals are poorly supported with policy impact evidence and are more like an uncritical shopping list… Given it is a policy paper, it is completely dominated by largely irrelevant biomedical findings, with policy proposals made as if they are somehow obvious, rather than a perturbation of a complex adaptive and interconnected market-based system for nicotine use

The question is what happens to demand for nicotine when you try to adjust behaviour against smokless tobacco use? We have already seen that excessive FDA regulation has caused the vast majority of the vape market to be traded through unauthorised and/or illicit channels. 

If the demand for nicotine is robust, the policy problem is to move to ways of using it that are much less harmful than the dominant method, smoking tobacco. ST, responsibly manufactured and marketed, is one such option.

Amen.

 

 

 

 

 

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