Electronic Nicotine-Delivery Systems for Smoking Cessation

Quick Takes

  • Addition of e-cigarettes to standard counseling was associated with greater abstinence from smoking compared to standard counseling alone.
  • However, rates of continued e-cigarette use were higher than in the standard counseling group.

Study Questions:

What is the efficacy and safety of electronic nicotine-delivery systems in assisting tobacco smokers to quit?


The investigators used an open-label controlled trial, ESTxENDS (Efficacy, Safety and Toxicology of Electronic Nicotine Delivery Systems as an Aid for Smoking Cessation), to randomly assign adult smokers to receive free e-cigarettes and e-liquids, standard-of-care smoking-cessation counseling, and optional (not free) nicotine replacement therapy, or to a control group, which received standard counseling and a voucher, which they could use for any purpose, including nicotine replacement therapy. Participants had to be currently smoking at least five tobacco cigarettes per day and were willing to set a quit date. The primary outcome was biochemically validated continuous abstinence from smoking at 6 months. Secondary outcomes included participant-reported abstinence from tobacco and from any nicotine (including smoking, e-cigarettes, and nicotine replacement therapy) at 6 months, respiratory symptoms, and serious adverse events.


A total of 1,246 participants from five Swiss sites were randomized including 622 assigned to the intervention group and 624 to the control group. Mean age of the participants was 38 years, and 47% identified as women. The mean (± standard deviation) number of days from the baseline visit to the target quit date was 6.0 ± 3.6 in the intervention group and 6.0 ± 3.9 in the control group. The percentage of participants with validated continuous abstinence from tobacco smoking was 28.9% in the intervention group and 16.3% in the control group (relative risk, 1.77; 95% confidence interval, 1.43-2.20). The percentage of participants who abstained from smoking in the 7 days before the 6-month visit was 59.6% in the intervention group and 38.5% in the control group. However, the percentage who abstained from any nicotine use was 20.1% in the intervention group and 33.7% in the control group. Serious adverse events occurred in 25 participants (4.0%) in the intervention group and in 31 (5.0%) in the control group; adverse events occurred in 272 participants (43.7%) and 229 participants (36.7%), respectively.


The authors conclude that the addition of e-cigarettes to standard smoking-cessation counseling resulted in greater abstinence from tobacco use among smokers than smoking-cessation counseling alone.


The randomized trial found greater cigarette quit rates among participants randomized to e-cigarettes and standard counseling compared to counseling alone. However, further research is warranted to understand how to reduce the use of e-cigarettes to prevent long-term use.

Clinical Topics: Prevention

Keywords: Electronic Nicotine Delivery Systems, Smoking Cessation

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