electronic nicotine delivery systems

Importance: Little is known about the relative effectiveness of nicotine-containing electronic cigarettes (ECs) compared with varenicline as smoking cessation aids.

Objective: To determine the relative effectiveness of ECs in smoking cessation.

Design, setting, and participants: This randomized placebo-controlled single-center trial was conducted in northern Finland. Participants aged 25 to 75 years who smoked daily and had volunteered to quit smoking were recruited from August 1, 2018, to February 20, 2020, via local media. The trial included 52 weeks of follow-up. All data analyses were conducted from September 1, 2022, to January 15, 2024. The participants, study nurses, and researchers were masked to group assignment.

Intervention: The participants were assigned by block randomization to receive 18 mg/mL of nicotine-containing ECs together with placebo tablets, varenicline with standard dosing together with nicotine-free ECs, or placebo tablets together with nicotine-free ECs, all combined with a motivational interview, with the intervention phase lasting for 12 weeks.

Main outcome and measure: The primary outcome was self-reported 7-day conventional cigarette smoking abstinence as confirmed by the exhaled carbon monoxide level on week 26. The analysis followed the intent-to-treat principle.

Results: Of the 561 recruited participants, 458 (81.6%) eligible participants (257 women [56%]; 201 men [44%]; mean [SD] age, 51 [11.6] years) were randomized. The primary outcome occurred in 61 of 152 participants (40.4%) in the EC group, 67 of 153 (43.8%) in the varenicline group, and 30 of 153 (19.7%) in the placebo group (P < .001). In the pairwise comparison, placebo differed statistically significantly from ECs (risk difference [RD], 20.7%; 95% CI, 10.4-30.4; P < .001) and varenicline (RD, 24.1%; 95% CI, 13.7-33.7; P < .001), but the difference was statistically insignificant between ECs and varenicline (RD, 3.4%; 95% CI, -7.6 to 14.3; P = .56). No serious adverse events were reported.

Conclusions: This randomized clinical trial found that varenicline and nicotine-containing ECs were both effective in helping individuals in quitting smoking conventional cigarettes for up to 6 months.

No abstract available.

INTRODUCTION:

E-cigarettes deliver an aerosol of nicotine by heating a liquid and are promoted as an alternative to combustible tobacco. This study determines the longitudinal associations between e-cigarette use and respiratory disease controlling for combustible tobacco use.

METHODS:

This was a longitudinal analysis of the adult Population Assessment of Tobacco and Health Waves 1, 2, and 3. Multivariable logistic regression was performed to determine the associations between e-cigarette use and respiratory disease, controlling for combustible tobacco smoking, demographic, and clinical variables. Data were collected in 2013-2016 and analyzed in 2018-2019.

RESULTS:

Among people who did not report respiratory disease (chronic obstructive pulmonary disease, chronic bronchitis, emphysema, or asthma) at Wave 1, the longitudinal analysis revealed statistically significant associations between former e-cigarette use (AOR=1.31, 95% CI=1.07, 1.60) and current e-cigarette use (AOR=1.29, 95% CI=1.03, 1.61) at Wave 1 and having incident respiratory disease at Waves 2 or 3, controlling for combustible tobacco smoking, demographic, and clinical variables. Current combustible tobacco smoking (AOR=2.56, 95% CI=1.92, 3.41) was also significantly associated with having respiratory disease at Waves 2 or 3. Odds of developing respiratory disease for a current dual user (e-cigarette and all combustible tobacco) were 3.30 compared with a never smoker who never used e-cigarettes. Analysis controlling for cigarette smoking alone yielded similar results.

CONCLUSIONS:

Use of e-cigarettes is an independent risk factor for respiratory disease in addition to combustible tobacco smoking. Dual use, the most common use pattern, is riskier than using either product alone.

BACKGROUND:

E-cigarettes are battery-operated devices that heat a liquid and deliver an aerosolized product to the user. Pulmonary illnesses related to e-cigarette use have been reported, but no large series has been described. In July 2019, the Wisconsin Department of Health Services and the Illinois Department of Public Health received reports of pulmonary disease associated with the use of e-cigarettes (also called vaping) and launched a coordinated public health investigation.

METHODS:

We defined case patients as persons who reported use of e-cigarette devices and related products in the 90 days before symptom onset and had pulmonary infiltrates on imaging and whose illnesses were not attributed to other causes. Medical record abstraction and case patient interviews were conducted with the use of standardized tools.

RESULTS:

There were 53 case patients, 83% of whom were male; the median age of the patients was 19 years. The majority of patients presented with respiratory symptoms (98%), gastrointestinal symptoms (81%), and constitutional symptoms (100%). All case patients had bilateral infiltrates on chest imaging (which was part of the case definition). A total of 94% of the patients were hospitalized, 32% underwent intubation and mechanical ventilation, and one death was reported. A total of 84% of the patients reported having used tetrahydrocannabinol products in e-cigarette devices, although a wide variety of products and devices was reported. Syndromic surveillance data from Illinois showed that the mean monthly rate of visits related to severe respiratory illness in June through August of 2019 was twice the rate that was observed in the same months in 2018.

CONCLUSIONS:

Case patients presented with similar clinical characteristics. Although the features of e-cigarette use that were responsible for injury have not been identified, this cluster of illnesses represents an emerging clinical syndrome or syndromes. Additional work is needed to characterize the pathophysiology and to identify the definitive causes.