Increasing Use and Knowledge Gaps Create Need for Individualized Patient Discussions
Subject Matter Experts: Dr. Kenneth Cummings, Dr. Matthew Carpenter, Dr. Pamela Morris
By Katharine Hendrix
On completion of this article, readers should be able to:
- Describe the current evidence regarding the health effects of e-cigarette use relative to smoking traditional cigarettes.
- Recognize key differences between vaping nicotine and smoking combusted tobacco.
- Identify knowledge gaps regarding e-cigarette use that future research should fill.
- Be able to tailor discussions about e-cigarette use to individual patient needs and health and smoking histories for those who: 1) smoke traditional cigarettes and want to quit; 2) failed previous quit attempts using guideline-recommended strategies; and 3) do not regularly smoke but report occasional e-cigarette use.
People smoke for the nicotine, but die from the toxins carried in the smoke. Separating nicotine from smoke is one way to make nicotine administration less dangerous. E-cigarettes (ECs) represent a class of products that use electricity to heat liquids containing nicotine to allow for nicotine administration with lower levels of exposure to the toxins found in cigarette smoke. By separating nicotine in an inhaled vapor without combusting tobacco, one can fundamentally change the conversation about smoking addiction and disease.1 ECs were first introduced in the US about 10 years ago. Prevalence of EC use among US adults is approximately four to six percent but is much higher among existing smokers (38 percent have ever used and 11 percent currently use ECs).2 Use of ECs is increasing rapidly and now represents the most commonly reported quitting aide used by smokers. Unfortunately, many healthcare providers are unprepared to discuss EC use with patients.
What are E-cigarettes?
The US Food and Drug Administration (FDA) regulates ECs as tobacco products because nicotine is derived from tobacco, although the majority of ECs do not contain any tobacco.3
ECs contain a battery, e-liquid reservoir, heating element or atomizer and mouthpiece. They operate by atomizing or heating the e-liquid (nicotine and flavoring chemicals dissolved in propylene glycol and/or glycerin) into a vapor that users inhale (a.k.a., “vaping”). Many ECs can be user-adjusted to deliver more or less nicotine per puff. A newer class of ECs, called “heat-not-burn” devices, do contain some tobacco but do not involve complete tobacco combustion. They generally deliver nicotine in a similar vaporized manner but with slightly higher levels of toxins than ECs.
Unknown Health Impacts
Because ECs are relatively new products and used differently from cigarettes, long-term studies documenting health outcomes are not available. Thus, many questions remain unanswered including the potential impacts of: long-term nicotine exposure, inhaling aerosolized e-liquid, heating e-liquids to high temperatures and ECs on population health indices.4
Known Health Impacts
Biomarker studies of EC users clearly show lower levels of exposure to toxins found in cigarette smoke. That said, EC vapor is not benign, and some products have been found to contain carbonyl compounds, oxidants, aldehydes, particulates and volatile organic compounds, albeit at lower levels than generally found in cigarette smoke.5 Nicotine, which is the primary psychoactive ingredient in cigarette smoke and EC vapor, is known to be addictive and potentially unsafe for pregnant women and those pre- disposed to cardiac problems. However, for non-pregnant, healthy adults, exposure to nicotine in the absence of tobacco smoke appears to be fairly safe. Nicotine may contribute to acute cardiovascular events and accelerated atherogenesis, but studies of “snus” users (a low nitrosamine smokeless tobacco) have not found increased risks of myocardial infarction or stroke. That said, studies do suggest nicotine may contribute to acute cardiovascular events in those with underlying coronary heart disease.6 Still, the risks from ECs appear to be far lower than from cigarette smoke exposure.
Comparison to Smoking Tobacco
Even if EC vapors contain harmful toxicants, studies consistently show that this vapor contains substantially fewer toxicants than tobacco smoke. It is generally agreed that ECs pose much lower health risks than smoking.4 A study comparing combusted tobacco and EC emissions that calculated lifetime cancer risks concluded that the cancer potency of ECs was less than 0.5 percent of
Although ECs may pose some cardiovascular risk, particularly in people with existing cardiovascular disease, comparisons indicate that the cardiovascular risks of vaping are probably lower than for smoking.6 Biomarker studies (including for acrolein, a potent respiratory irritant) find similar levels among EC users and non-smokers.4 No second-hand exposure risks from EC vapor have yet been identified.
A 2018 review concluded that vaping poses a fraction of the risks of smoking and switching from smoking to vaping conveys substantial health benefits.4 Even if smokers partially switch and engage in
“dual use” of both combusted cigarettes and ECs, individual harm is likely reduced as well, though quantifying this level of reduced risk is difficult, as some dual users predominantly smoke and only occasionally vape, while others predominately vape and only smoke occasionally.
Discussing E-cigarettes with Patients
While we wait for conclusive studies and guideline updates, EC use is increasing. Although not FDA-approved for cessation, ECs are the most popular quit aid among smokers and evidence indicates that EC use may increase cessation rates.7 Other reasons for EC use are curiosity, flavor and perception of lower health risks than smoking.
US smoking cessation guidelines were last updated in 2008 and do not address ECs.8 So, how might providers discuss EC use with their patients? Extensive literature on health behavior change emphasizes tailoring discussions to the individual’s readiness and prior attempts to change.9 That is, different types of patients need different information.
Type 1: The patient is ready to quit. Provide the currently recommended strategies of counseling (individual or group) and medication (FDA-approved nicotine replacement gum, inhaler, lozenge, nasal spray, and/or patch and/or bupropion or varenicline). Of these, varenicline and combination nicotine replacement has shown superior efficacy.
Type 2: The patient is not contemplating quitting. Discuss the health risks of smoking, strongly encourage smoking cessation and provide information regarding counseling and cessation aids that can be prescribed when they are ready to quit. If the patient is unwilling to try FDA-approved methods to quit, discussion of ECs as an alternative is warranted.
Type 3: The patient previously tried quitting with evidence-based, FDA-approved strategies but failed. Discuss switching from smoking tobacco to using ECs. Emphasize that: 1) ECs are less harmful but not harmless; 2) long-term effects are unknown; and 3) the goal is to eventually stop using ECs.
Type 4: The patient does not smoke combustible tobacco but occasionally “vapes.” Advise against using ECs–especially for adolescents and young adults. Emphasize that: 1) ECs are not harmless; 2) nicotine is addictive and harmful; and 3) many health impacts are unknown.
The information below provides responses to questions that patients may ask about ECs.1
What is the best way to stop smoking?
- Behavioral counseling combined with FDA-approved stop-smoking medications (ie, nicotine replacement therapies, varenicline, bupropion) is the most effective treatment.
- ECs have not been approved as a stop-smoking treatment by the FDA. However, smokers who cannot stop smoking with FDA- approved medications may benefit from ECs as a cessation aid, though evidence is limited.
- Because ECs deliver nicotine, they are likely to help reduce urges to smoke and ease withdrawal from cigarettes.
Are ECs safe?
- ECs are not risk free, but evidence suggests they expose users to much lower levels of toxins when compared to combustible tobacco cigarettes.
- Long-term risks are unknown, but common side effects include irritation of the mouth and throat and dry cough. You should stop using ECs after successful cessation of tobacco cigarettes.
- Ingestion of nicotine liquids can be dangerous. Keep e-liquids in childproof containers and out of the reach of children.
- Protect EC devices from extreme temperatures by not leaving them in direct sunlight or in a vehicle during freezing temperatures.
- Avoid vape battery explosions by:
- Using devices with safety features such as button locks, vent holes and overcharging protection;
- Keeping batteries in a case to prevent contact with metal objects (i.e., coins, keys);
- Not charging the device with a phone or tablet charger; d. Not charging the device unattended; and
- Replacing batteries if they get damaged or wet.
What type of EC should I use?
- There are many different models of ECs with different levels of nicotine delivery and flavors, and more advanced models deliver nicotine more efficiently and seem to work best for those trying to quit smoking tobacco cigarettes.
- Carefully read and understand the manufacturer’s recommendations for use and care of the EC. If the device did not come with instructions or you have further questions, contact the manufacturer.
- Go to the FDA website for updates on ECs and safety information at: https://bit.ly/2noucJr.
How should I use EC?
- Daily EC use is generally more effective for quitting smoking than intermittent use.
- It may take practice to deliver the proper amount of nicotine needed to relieve the urge to smoke.
- Stop use of combustible tobacco cigarettes as soon as possible and discontinue ECs when you are comfortable that you have quit cigarette smoking for good.
- Avoid dual use of cigarettes and ECs if possible.
- ECs may be used along with an FDA-approved stop-smoking medication such as a nicotine patch or varenicline.
Where can I use ECs?
- Many public places do not allow smoking or use of ECs indoors.
- While the risks from secondhand vape are lower than from secondhand smoke, it is best to vape outdoors and not around others.
1 Cummings, KM, et al. Another paper about e-cigarettes: Why should I care? JAHA, 2018. 14:7(14).
2 Levy DT, et al. The Prevalence and Characteristics of E-Cigarette Users in the U.S. Int J Environ Res Public Health. 2017;14(10):1200.
3 U.S. Department of Health and Human Services. Office of the Surgeon General. E-Cigarette Use Among Youth and Young Adults: A Report of the Surgeon General. 2016.
4 McNeil A, et al. Evidence Review of E-cigarettes and Heated Tobacco Products 2018. Commissioned by Public Health England: An executive agency of the Department of Health and Social Care.
5 U.S. Department of Health and Human Services. Office of the Surgeon General. E-Cigarette Use Among Youth and Young Adults: A Report of the Surgeon General. 2016.
6 Benowitz NL and Fraiman JB, Cardiovascular Effects of Electronic Cigarettes. Nat Rev Cardiol, 2017. 14:8;447-456.
7 Carpenter MJ, et al. A Naturalistic, Randomized Pilot Trial of E-Cigarettes: Uptake, Exposure, and Behavioral Effects. Cancer Epidemiol Biomarkers Prev. 2017;26(12):1795-1803.
8 Fiore et al. Treating Tobacco Use and Dependence. Content last reviewed April 2013. Agency for Healthcare Research and Quality, Rockville, MD.
9 Prochaska, JO and Velicer, WF. The Transtheoretical Model of Health Behavior Change. AJHP, 1997.1211:38-48.