The effect of e-cigarettes on smoking cessation and cigarette smoking initiation: An evidence-based rapid review and meta-analysis

Abstract

INTRODUCTIONElectronic cigarettes, also called e-cigarettes are electronic nicotine delivery systems (ENDS). They can deliver vaporized liquid mainly containing nicotine and propylene glycol through the mouth into the lungs, mimicking the effects of conventional cigarette smoking 1 . Reportedly, the e-cigarette was invented by the Chinese pharmacist Hon Lik in 2003, and internationally patented in 2007 2 . E-cigarettes have been commercially available in Europe and America since 2006 as a cigarette substitute 3 . E-cigarettes have always been advertised as healthy and popular ABSTRACT INTRODUCTION The contribution made by e-cigarettes to smoking cessation continues to be controversial. Reports suggest that teenagers are becoming increasingly addicted to e-cigarettes and that e-cigarette use in adolescents is associated with subsequent cigarette smoking. METHODS Systematic searches of eleven databases were conducted (January 2015 to June 2020). Systematic reviews, randomized controlled trials (RCTs) and cohort studies comparing e-cigarettes with placebo e-cigarettes, nicotine replacement therapy (NRT) or no e-cigarette use were included. The two primary outcomes were smoking cessation among smokers and smoking initiation among non-smoking teenagers. The secondary outcome was adverse events. Data were synthesized using risk ratio (RR) or adjusted odds ratio (AOR) with 95% confidence interval (CI). RESULTS Six systematic reviews, 5 RCTs and 24 cohort studies were identified. For smoking cessation, findings from 4 systematic reviews indicated that e-cigarettes contributed to cessation while one found the opposite. Meta-analysis of 5 RCTs suggested that e-cigarettes were superior to NRT or placebo for smoking cessation (RR=1.55; 95% CI: 1.00-2.40; I 2 =57.6%; low certainty; 5 trials, n=4025). Evidence from 9 cohort studies showed that e-cigarette use was not associated with cessation (AOR=1.16; 95% CI: 0.88-1.54; I 2 =69.0%; n=22220). Subgroup analysis suggested that intensive e-cigarette use may be associated with cessation. In terms of smoking initiation, adolescents who ever used e-cigarettes had a greater risk for smoking initiation than non-users (AOR=2.91; 95% CI: 2.61-3.23; I 2 =61.0%; 15 trials, n=68943), the findings were consistent with one included systematic review. No serious adverse events were reported in the included studies. CONCLUSIONS Low certainty evidence suggests that e-cigarettes appear to be potentially effective for smoking cessation. The use of e-cigarettes in adolescents may be associated with smoking initiation. No serious adverse events were reported.

Chemosensory Contributions of E-Cigarette Additives on Nicotine Use

“…From 2017 to 2018, e-cigarette use, commonly referred to as vaping, among high school students almost doubled from 11.7 to 20.8% ( Centers for Disease Control and Prevention [CDC], 2019 ). E-cigarettes are marketed as smoking cessation aids, and while there may be some merit to these claims ( Hartmann-Boyce et al, 2021 ; Zhang et al, 2021 ), other studies disagree ( Chen et al, 2020 ) and even point to e-cigarettes as a cause of relapse in former smokers ( Baenziger et al, 2021 ). Furthermore, many young e-cigarette users are “nicotine-naïve,” having never smoked nor used tobacco products before initiating e-cigarette use.…”

“…Nicotine use, especially during adolescence, results in short- and long-term detriments to brain development ( Slotkin, 2004 ; Yuan et al, 2015 ; Leslie, 2020 ), reward processing ( Mansvelder et al, 2002 ; Hilario et al, 2012 ; Ren and Lotfipour, 2019 ), and overall health ( Picciotto et al, 2002 ; Lee and Cooke, 2011 ; Kutlu et al, 2015 ). Several studies have also found that initiation of e-cigarette use in adolescence or adulthood increases the likelihood of later combustible cigarette use ( Barrington-Trimis et al, 2016 ; Berry et al, 2019 ; Baenziger et al, 2021 ; Hair et al, 2021 ; Zhang et al, 2021 ), which is alarming considering that smoking remains the leading cause of preventable death and disease in the United States ( Centers for Disease Control and Prevention [CDC], 2020 ). The rapid rise in e-cigarette popularity and subsequent nicotine use, especially among youth, has sparked a public health concern.…”

Quit Smoking Weapons of Mass Distraction

“…• (2021) Wang et al: Meta-analysis of 55 observational studies: "As consumer products, in observational studies, e-cigarettes were not associated with increased smoking cessation in the adult population" (Wang, Bhadriraju et al 2021). • (2021) Zhang et al: "Evidence from 9 cohort studies showed that e-cigarette use was not associated with cessation" (Zhang, Bu et al 2021). • ( 2021) WHO: "To date, evidence on the use of ENDS [Electronic Nicotine Delivery Systems] as a cessation aid is inconclusive" (World Health Organization 2021).…”

A scoping review on disparities in exposure to advertising for e-cigarettes and heated tobacco products and implications for advancing a health equity research agenda

“…A study found that e-cigarette advertising in the U.S contained youth-appealing features [ 28 ]. Research has also shown that e-cigarette use may result in transitions to cigarette smoking [ 29 ], leading to further concerns about how these devices may affect existing disparities in health outcomes related to tobacco. Current research in this regard has not been fully explored; a systematic review found different patterns for e-cigarette awareness, ever use, and current use based on sociodemographic characteristics, highlighting the need to ensure the potential benefits and risks of e-cigarettes do not increase current health disparities [ 30 ].…”