The new research, presented yesterday at the Sixth Scientific Symposium of the Flight Attendant Medical Research Institute (FAMRI), studied the effect of nicotine-free cigarettes on cardiovascular disease risk in smokers, as measured by levels of platelet activity in the blood (higher levels of platelet activity indicate a more thrombotic state – a state more conducive to clot formation and therefore to the development of cardiovascular disease) (Girdhar G, Xu S, Jesty J, Bluestein D. Abstract – Nicotine reduction and elimination in cigarettes – its effect on cardiovascular risk in smokers, and in non-smokers exposed to secondhand smoke).
The researchers, from the State University of New York at Stony Brook, examined the effect on platelet activity of switching smokers from a low-nicotine to a zero-nicotine cigarette. They found that platelet activation increased significantly more among smokers who switched to zero-nicotine cigarettes than among those who continued to smoke low-nicotine cigarettes. In other words, nicotine did appear to suppress to some extent the platelet activating effect of cigarette smoking. Thus, the absence of nicotine led to higher levels of platelet activation, which would be expected to yield a more thrombotic state, and a higher cardiovascular disease risk.
The researchers wrote: “With regard to platelet activation – a clear marker of cardiovascular risk – we conclude that these [zero-nicotine] cigarettes may be substantially more pro-thrombotic than nicotine-containing cigarettes. … Nicotine in tobacco smoke of low-nicotine cigarettes significantly protects platelets against activation by non-nicotine smoke components. Accordingly, the reduction or elimination of nicotine from cigarettes may render them more harmful.”
The researchers concluded: “Removal of nicotine from cigarettes is dangerous for smokers and may increase risk of cardiovascular disease.”
The Rest of the Story
This new research is quite intriguing and it has some important implications for consideration of the proposed FDA tobacco legislation being promoted by Philip Morris and by a number of major anti-smoking groups. The results of the research are not intuitive; in fact, they may seem unexpected to those who were not previously familiar with the existing research showing in vitro, nicotine exhibits some suppressive effects on platelet activity. These new findings, which demonstrate this effect in vivo, suggest that the proposed FDA legislation may end up harming the public’s health not only because a reduction in nicotine levels may lead to increased tar delivery due to compensation, but also because greatly reduced nicotine cigarettes may be more pro-thrombotic and therefore more dangerous.
The purpose of this research was apparently to evaluate the health effects of new low- and zero-nicotine cigarettes being marketed by Vector Group (Quest cigarettes). The research shows that despite having very low or no nicotine, these cigarettes may not be safer for smokers, and that they may in fact be more hazardous due to reduction of the platelet activation suppression function of nicotine.
Although not the primary purpose of the research, it also has important implications for the evaluation of a government-mandated reduction in nicotine levels in cigarettes. The research cautions us that a strategy of mandating reductions in the nicotine content of cigarettes could be harmful to smokers, and therefore in conflict with the goal of protecting the public’s health.
This adds to the concern that I expressed previously about the potential for compensation by smokers in order to maintain a constant nicotine dose in the face of mandatory reductions in nicotine content of cigarettes.
It also adds to the concern over increased carbon monoxide levels produced by very low nicotine cigarettes, which would also be expected to increase disease risk.
The bottom line is this: we simply do not know what the effect of reduction of particular components of cigarettes – including nicotine – would be. Therefore, it is completely unwarranted to make a claim that the proposed legislation will protect the public’s health and/or save lives, as several of the major anti-smoking groups have asserted.It is just as likely that the proposed regulation by the FDA could lead to changes that increase the health risks of cigarettes and kill people, rather than save lives.