Applied Evidence

E-cigarettes: How “safe” are they?

J Fam Pract. 2016 June;65(6):380-385

From The Journal of Family Practice | 2016;65(6):380-385.

References

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Don’t substitute one form of nicotine for another

The presence of lead, cadmium, and nickel in inhaled e-cigarette vapor is an area of significant concern.

The USPSTF has not determined the benefit-to-harm ratio of using e-cigarettes as a smoking cessation aid, but recommends prescribing behavioral techniques and/or pharmacologic alternatives instead.³² Because the devices have been promoted as an aid to smoking cessation, intention to quit using tobacco products is a reason often stated for utilizing e-cigarettes.^2,33,34Indeed, use of e-cigarettes is much more likely among those who already utilize tobacco products.^35-37

At least one study reports that e-cigarettes have efficacy similar to nicotine patches in achieving smoking abstinence among smokers who want to quit.³⁸ Former smokers who used e-cigarettes to quit smoking reported fewer withdrawal symptoms than those who used nicotine skin patches.³⁹ In addition, former smokers were more likely to endorse e-cigarettes than nicotine patches as a tobacco cigarette cessation aid. Significant reduction in tobacco smoke exposure has been demonstrated in dual users of tobacco and electronic cigarettes;^40,41however, both of these nicotine delivery systems sustain nicotine addiction.

Despite many ongoing studies to determine if e-cigarettes are useful as a smoking cessation aid, the results vary widely and are inconclusive at this time.⁴²

E-cigarettes do not increase long-term tobacco abstinence

Contrary to popular belief, research shows that e-cigarette use among smokers is not associated with long-term tobacco abstinence.¹ E-cigarette users, however, may make more attempts to quit smoking compared with smokers not using them.⁴³ In addition, even though there is some evidence that e-cigarettes help smokers reduce the number of cigarettes smoked per day, simply reducing the daily number of cigarettes does not equate with safety.⁴⁴ Smoking just one to 4 cigarettes per day poses 3 times the risk of myocardial infarction and lung cancer compared with not smoking.⁴⁴ And since many individuals continue to use traditional and electronic cigarettes, they end up in double jeopardy of toxicity through exposure to the dangers of both.

A gateway to other substances of abuse?

Pregnant and breastfeeding women should not replace tobacco cigarettes with e-cigarettes.

There is also fear that nicotine exposure via e-cigarettes, especially in young people, serves as a “gateway” to tobacco consumption and other substance abuses, and increases the risk for nicotine addiction.³⁴Such nicotine-induced effects are a result of changes in brain chemistry, and have been documented in humans and animals.³⁴

These concerns about negative health consequences, combined with the fact that e-cigarettes are undocumented as a smoking cessation aid, add urgency to the need for legislative and regulatory actions that hopefully can curb all nicotine exposures, particularly for our nation’s youth. In the meantime, it is important for physicians to advise patients—and the public—about the risks of e-cigarettes and the importance of quitting all forms of nicotine inhalation because nicotine—regardless of how it is delivered—is still an addictive drug.

CORRESPONDENCE
Steven Lippmann, MD, University of Louisville School of Medicine, 401 E. Chestnut Street, Suite 610, Louisville, KY 40202; sblipp01@louisville.edu.