Quitting Smoking / Preventing Relapse

2010

Effect of an electronic nicotine delivery device (e cigarette) on desire to smoke and withdrawal, user preferences and nicotine delivery: randomised cross-over trial

C Bullen, H McRobbie, S Thornley, M Glover, R Lin, M Laugesen
Published online: 8 Apr 2010

Conclusions “The 16 mg Ruyan V8 ENDD alleviated desire to smoke after overnight abstinence, was well tolerated and had a pharmacokinetic profile more like the Nicorette inhalator than a tobacco cigarette. Evaluation of the ENDD for longer-term safety, potential for long-term use and efficacy as a cessation aid is needed.”

Electronic cigarettes: a survey of users

Jean-François Etter
Published online: 4 May 2010

Our results suggest that e-cigarettes are used mainly to quit smoking, and may be useful for this purpose.

2011

Effect of an electronic nicotine delivery device (e-Cigarette) on smoking reduction and cessation: a prospective 6-month pilot study

Riccardo Polosa, Pasquale Caponnetto, Jaymin B Morjaria, Gabriella Papale, Davide Campagna, Cristina Russo
Published online: 11 Oct 2011

Sustained 50% reduction in the number of cig/day at week-24 was shown in 13/40(32.5%) participants; their median of 25 cigs/day decreasing to 6 cigs/day (p < 0.001). Sustained 80% reduction was shown in 5/40(12.5%) participants; their median of 30 cigs/day decreasing to 3 cigs/day (p = 0.043). Sustained smoking abstinence at week-24 was observed in 9/40(22.5%) participants, with 6/9 still using the e-Cigarette by the end of the study. Combined sustained 50% reduction and smoking abstinence was shown in 22/40 (55%) participants, with an overall 88% fall in cigs/day.

The use of e-Cigarette substantially decreased cigarette consumption without causing significant side effects in smokers not intending to quit 

Electronic cigarette: users profile, utilization, satisfaction and perceived efficacy

Jean-François Etter, Chris Bullen
Published online: 18 May 2011

Almost all (97%) used e‐cigarettes containing nicotine.

Most (96%) said the e‐cigarette helped them to quit smoking or reduce their smoking (92%). 

Reasons for using the e‐cigarette included the perception that it was less toxic than tobacco (84%), to deal with craving for tobacco (79%) and withdrawal symptoms (67%), to quit smoking or avoid relapsing (77%), because it was cheaper than smoking (57%) and to deal with situations where smoking was prohibited (39%). 

Most ex‐smokers (79%) feared they might relapse to smoking if they stopped using the e‐cigarette. 

Users of nicotine‐containing e‐cigarettes reported better relief of withdrawal and a greater effect on smoking cessation than those using non‐nicotine e‐cigarettes.

Electronic cigarettes (e-cigs): views of aficionados and clinical/public health perspectives

J. Foulds, S. Veldheer, A. Berg
Published online: 11 Aug 2011

The health risks from smoking are large and are known with certainty. Comparatively, the health risks from e‐cig use are likely much smaller (if any) and temporarily switching to e‐cigs will likely yield a large health benefit. 

If the patient perceives that the e‐cig is helping them to stay off cigarettes and is not reporting any health problems likely attributable to the e‐cig, then the focus should be on staying smoke‐free rather than e‐cig free. 

Electronic Cigarettes As a Smoking-Cessation Tool: Results from an Online Survey

Michael B.Siegel, Kerry L.Tanwar, Kathleen S.Wood
Published online: 1 Apr 2011

A large percentage of respondents reported a reduction in the number of cigarettes they smoked (66.8%) and almost half reported abstinence from smoking for a period of time (48.8%). Those respondents using e-cigarettes more than 20 times per day had a quit rate of 70.0%. Of respondents who were not smoking at 6 months, 34.3% were not using e-cigarettes or any nicotine-containing products at the time.

The distinct and unique advantage of e-cigarettes is that they allow individuals to utilize one device that can simultaneously address nicotine withdrawal, psychological factors, and behavioural cues that serve as barriers to smoking abstinence. 

Interviews With “Vapers”: Implications for Future Research With Electronic Cigarettes

Amy McQueen, Stephanie Tower, Walton Sumner
Published online: 9 Sep 2011

Experienced users report health gains typical for smoking cessation despite continued vaping.

There were pervasive themes including the language and culture of vaping; social and informational support among vapers, motives and perceived benefits of using e-cigs versus cigarettes including cigarette-like enjoyment, cost, restored sense of taste and smell, and improved breathing and exercise tolerance; rapidly reduced nicotine tolerance and dependence; and a strong interest in e-cig–related research and policy.

2012

The electronic-cigarette: Effects on desire to smoke, withdrawal symptoms and cognition

Lynne Dawkins, John Turner, Surrayyah Hasna, Kirstie Soar
Published online: Aug 2012

The e-cigarette can reduce desire to smoke and nicotine withdrawal symptoms 20 minutes after use.

The nicotine content in this respect may be more important for males.

The first study to demonstrate that the nicotine e-cigarette can improve working memory.

2013

E-Cigarettes: Prevalence and Attitudes in Great Britain

Martin Dockrell, Rory Morrison, Linda Bauld, Ann McNeill
Published online: 10 Oct 2013

While we found evidence supporting the view that e-cigarette use may be a bridge to quitting, we found very little evidence of e-cigarette use among adults who had never smoked. British smokers would benefit from information about the effective use, risks, and benefits of e-cigarettes, as this might enable the use of e-cigarettes to improve public health.

EffiCiency and Safety of an eLectronic cigAreTte (ECLAT) as Tobacco Cigarettes Substitute: A Prospective 12-Month Randomized Control Design Study

Pasquale Caponnetto, Davide Campagna, Fabio Cibella, Jaymin B. Morjaria, Massimo Caruso, Cristina Russo, Riccardo Polosa
Published online: 24 Jun 2013

Conclusion: “In smokers not intending to quit, the use of e-cigarettes, with or without nicotine, decreased cigarette consumption and elicited enduring tobacco abstinence without causing significant side effects.” 

'Vaping' profiles and preferences: an online survey of electronic cigarette users

Lynne Dawkins, John Turner, Amanda Roberts, Kirstie Soar
Published online: 28 Mar 2013

FINDINGS: Seventy-four percent of participants reported not smoking for at least a few weeks since using the e-cigarette and 70% reported reduced urge to smoke. Seventy-two percent of participants used a ‘tank’ system, most commonly, the eGo-C (23%). Mean duration of use was 10 months. Only 1% reported exclusive use of non-nicotine (0 mg) containing liquid. E-cigarettes were generally considered to be satisfying to use; elicit few side effects; be healthier than smoking; improve cough/breathing; and be associated with low levels of craving. Among ex-smokers, ‘time to first vape’ was significantly longer than ‘time to first cigarette’ (t1104  = 11.16, P < 0.001) suggesting a lower level of dependence to e-cigarettes. Ex-smokers reported significantly greater reduction in craving than current smokers (χ(2) 1  = 133.66, P < 0.0007) although few other differences emerged between these groups. Compared with males, females opted more for chocolate/sweet flavours (χ(2) 1  = 16.16, P < 0.001) and liked the e-cigarette because it resembles a cigarette (χ(2) 3  = 42.65, P < 0.001).

CONCLUSIONS: E-cigarettes are used primarily for smoking cessation, but for a longer duration than nicotine replacement therapy, and users believe them to be safer than smoking.”

2014

Effectiveness of the Electronic Cigarette: An Eight-Week Flemish Study with Six-Month Follow-up on Smoking Reduction, Craving and Experienced Benefits and Complaints

Karolien Adriaens, Dinska Van Gucht, Paul Declerck, Frank Baeyens
Published online: 29 Oct 2014

When people, ready to switch to an e-cig, are severely restricted in terms of accessibility of nicotine-containing e-liquids, the success of e-cigs may be endangered. For the e-cig to be and remain successful, it is important that people have easy access to nicotine containing e-liquids.

Conclusion: “In a series of controlled lab sessions with e-cig-naïve tobacco smokers, second-generation e-cigs were shown to be immediately and highly effective in reducing abstinence-induced cigarette craving and withdrawal symptoms, while not resulting in increases in eCO. Ad libitum use of e-cigs—in between and until six months after the lab sessions—resulted in remarkable reductions in or (biologically confirmed) complete abstinence from tobacco smoking in almost half of the participants who had no intention to quit smoking. [highlighting added] Eight months after the start of the study 21% of all participants were completely abstinent from tobacco cigarettes. Similar reduction/cessation rates were obtained with guided versus non-guided switching to e-cigs. Part of the observed efficacy of e-cigs in this study may be related to the fact that they allowed to maintain relatively high blood nicotine levels and showed an excellent experienced benefits/complaints ratio, especially in comparison with continued tobacco smoking”…

E-cigarette is an attractive long-term alternative and safer source of nicotine to conventional cigarette. Since their invention in 2003, there has been constant innovation and development of more efficient and appealing products. Here we show for the first time that second generation PVs can substantially decrease cigarette consumption without causing significant side effects in smokers not intending to quit. Moreover, overall participants’ perception and acceptance of these products was very good, in particular for those who quit or reduced smoking. Compared to our earlier work with first generation “cig-alikes”, technical problems and difficulties in use familiarization with second generation PVs were negligible. Improved products reliability and attractiveness might have contributed to the very low number of study failures and lost to follow-up and high success rates thus confirming the notion that these products are attractive substitutes for conventional cigarettes. Although large and carefully conducted RCTs will be required to confirm these preliminary encouraging observations, the notion that second generation PVs can substantially decrease cigarette consumption in smokers not intending to quit should be taken into consideration by regulatory authorities seeking to adopt proportional measures for the vapour category 

Success rates with nicotine personal vaporizers: a prospective 6-month pilot study of smokers not intending to quit

Riccardo Polosa, Pasquale Caponnetto, Marilena Maglia, Jaymin B Morjaria, Cristina Russo
Published online: 8 Nov 2014

Complete tobacco cessation is the best outcome for smokers, but the powerful addictive qualities of nicotine and of the ritualistic behaviour of smoking create a huge hurdle, even for those with a strong desire to quit. Tobacco harm reduction (THR), the substitution of low-risk nicotine products for cigarette smoking, is a realistic strategy for smokers who have difficulty quitting. E-cigarettes are the newest and most promising products for THR. This approach has been recently exploited to reduce or reverse the burden of harm in smokers with mental health disorders and chronic airway disease

Characteristics, Perceived Side Effects and Benefits of Electronic Cigarette Use: A Worldwide Survey of More than 19,000 Consumers

Konstantinos E. Farsalinos, Giorgio Romagna, Dimitris Tsiapras, Stamatis Kyrzopoulos, Vassilis Voudris
Published online: 22 Apr 2014

The main results of this survey indicate that ECs may be an effective substitute for smoking even in highly dependent subjects who are heavy smokers. Significant benefits are experienced by these people in physiologic functions and in some disease conditions, with former smokers (those who completely substituted smoking with EC use) being more likely to report such beneficial effects.

Both former and current smokers initiated EC use with high nicotine-containing liquids. More than one-fifth of the population initiated use with more than 20 mg/mL nicotine concentration, with higher prevalence in former smokers, supporting the hypothesis that nicotine plays an important role in the success of ECs as smoking substitutes [4,16]. This can be attributed to the lower nicotine absorption from EC use compared to smoking [13,17,18]. Such repeated observations should be taken into consideration by the regulatory authorities.

The most important reasons for participants to initiate ECs were to reduce or completely quit smoking and to reduce exposure of family members to second-hand smoking. It seems that these subjects are well-informed about the adverse health effects of smoking and are willing to try an alternative product which they consider less harmful.

In conclusion, in this large sample of dedicated EC users, it seems that ECs are used as long-term substitutes to smoking. They can be effective even in subjects who are highly dependent on smoking and are heavy smokers. Mild temporary side-effects and significant benefits are reported by this population. Motivation for using ECs comes from their expected less harmful potential compared to smoking.

Reasons for quitting cigarette smoking and electronic cigarette use for cessation help.

Pokhrel, P., & Herzog, T. A.
Published online: 1 Sep 2014

Thus, this may be the first study to suggest that smokers who want to quit smoking for immediate, extrinsic rewards may be attracted to use e-cigarettes to stop smoking cigarettes than smokers who want to quit smoking for intrinsic reasons such as health concerns. In conclusion, e-cigarettes appear to provide a “smoking” alternative to a section of cigarette smokers who may not quit smoking for health reasons. Public health efforts may need to consider employing e-cigarettes to promote tobacco-related harm reduction.

Cigarette Users’ Interest in Using or Switching to Electronic Nicotine Delivery Systems for Smokeless Tobacco for Harm Reduction, Cessation, or Novelty: A Cross-Sectional Survey of US Adults

Carla J. Berg, Regine Haardoerfer, Cam Escoffery, Pinpin Zheng, Michelle Kegler
Published online: 20 Jun 2014

This study highlights higher interest in ENDS versus smokeless tobacco and greater interest in both for harm reduction and cessation than due to novelty or smoking restrictions. 

27.2% of current smokers had talked with a health care provider about ENDS, with 18.0% reporting that their provider endorsed ENDS use for cessation. 

Developing educational campaigns and informing practitioners about ENDS as cessation or harm reduction aids is critical.

2015

E-Cigarettes and Smoking Cessation: Evidence from a Systematic Review and Meta-Analysis

Muhammad Aziz Rahman, Nicholas Hann, Andrew Wilson, George Mnatzaganian, Linda Worrall-Carter
Published online: 30 Mar 2015

Conclusions: “This systematic review and meta-analyses assessed the findings of six studies which reported smoking cessation after using e-cigarettes. We found an association between nicotine-enriched e-cigarette use and smoking cessation, suggesting that the devices may be an effective alternative smoking cessation method. We also found that use of e-cigarettes was also associated with a reduction in the number of cigarettes used, suggesting they may also have a role in tobacco harm reduction programs. To our knowledge, this is the most comprehensive evidence to date on this issue, and while there are a number of important implications for further research, these findings provide timely information to inform regulatory strategies.”

A Longitudinal Study of Electronic Cigarette Use Among a Population-Based Sample of Adult Smokers: Association With Smoking Cessation and Motivation to Quit

Lois Biener, J. Lee Hargraves
Published online: Feb 2015

Results: At follow-up, 23% were intensive users, 29% intermittent users, 18% had used once or twice, and 30% had not tried e-cigarettes. Logistic regression controlling for demographics and tobacco dependence indicated that intensive users of e-cigarettes were 6 times more likely than non-users/triers to report that they quit smoking (OR: 6.07, 95% CI = 1.11, 33.2). No such relationship was seen for intermittent users. There was a negative association between intermittent e-cigarette use and 1 of 2 indicators of motivation to quit at follow-up.

Conclusion: Daily use of electronic cigarettes for at least 1 month is strongly associated with quitting smoking at follow-up. Further investigation of the underlying reasons for intensive versus intermittent use will help shed light on the mechanisms underlying the associations between e-cigarette use, motivation to quit, and smoking cessation.

Associations Between E-Cigarette Type, Frequency of Use, and Quitting Smoking: Findings From a Longitudinal Online Panel Survey in Great Britain

Sara C. Hitchman, Leonie S. Brose, Jamie Brown, Debbie Robson, Ann McNeill
Published online: Oct 2015

Conclusion: Whether e-cigarette use is associated with quitting depends on type and frequency of use. Compared with respondents not using e-cigarettes, daily tank users were more likely, and non-daily cigalike users were less likely, to have quit. Tanks were more likely to be used by older respondents and respondents with lower education

Electronic Cigarettes Efficacy and Safety at 12 Months: Cohort Study

Lamberto Manzoli , Maria Elena Flacco , Maria Fiore, Carlo La Vecchia, Carolina Marzuillo, Maria Rosaria Gualano, Giorgio Liguori, Giancarlo Cicolini, Lorenzo Capasso, Claudio D'Amario, Stefania Boccia, Roberta Siliquini, Walter Ricciardi, Paolo Villari
Published online: 10 Jun 2015

Results: Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers…

2016

Patterns of Electronic Cigarette Use Among Adults in the United States

Cristine D. Delnevo, Daniel P. Giovenco, Michael B. Steinberg, Andrea C. Villanti, Jennifer L. Pearson, Raymond S. Niaura, David B. Abrams
Published online: May 2016

Results: Current e-cigarette use is extremely low among never cigarette smokers (0.4%) and former smokers who quit cigarettes 4 or more years ago (0.8%). Although e-cigarette experimentation is most common among current cigarette smokers and young adults, daily use is highest among former smokers who quit in the past year (13.0%) and older adults. Compared to daily cigarette smokers, recently quit smokers were more than four times as likely to be daily users of e-cigarettes ( AOR : 4.33 [95% CI: 3.08–6.09]).

Conclusion: Extremely low e-cigarette use among never-smokers and longer term former smokers suggest that e-cigarettes neither promote widespread initiation nor relapse among adults. Recognition of the heterogeneity of smokers, including the time since quitting, is critical to draw accurate conclusions about patterns of e-cigarette use at the population level and its potential for public health benefit or harm.

Electronic cigarette use in the European Union: analysis of a representative sample of 27 460 Europeans from 28 countries

Konstantinos E. Farsalinos, Konstantinos Poulas, Vassilis Voudris, Jacques Le Houezec
Published online: 24 Jun 2016

E‐cigarette use in the European Union appears to be largely confined to current or former smokers, while current use and nicotine use by people who have never smoked is rare. More than one‐third of current e‐cigarette users polled reported smoking cessation and reduction.

2017

Predicting Short-Term Uptake of Electronic Cigarettes: Effects of Nicotine, Subjective Effects, and Simulated Demand

Megan R Tucker, Murray Laugesen, Chris Bullen, Randolph C Grace
Published online: 20 Dec 2017

Mean cigarettes per day decreased by 37% when e-cigarettes were available relative to baseline. Nicotine-containing cartridges were associated with greater use and craving reduction than 0 mg. Alleviation of withdrawal symptoms and taste and enjoyment factors predicted e-cigarette use.

Cohort study of electronic cigarette use: effectiveness and safety at 24 months

Lamberto Manzoli, Maria Elena Flacco, Margherita Ferrante, Carlo La Vecchia, Roberta Siliquini, Walter Ricciardi, Carolina Marzuillo, Paolo Villari, Maria Fiore
Published online: 19 Apr 2017

Of the e-cigarette users, 61.1% remained abstinent from tobacco (while 23.1% and 26.0% of tobacco-only smokers and dual users achieved tobacco abstinence).

2018

Advice From Former-Smoking E-Cigarette Users to Current Smokers on How to Use E-Cigarettes as Part of an Attempt to Quit Smoking

Christopher Russell, Tiffany Dickson, Neil McKeganey
Published online: Aug 2018

This study describes the advice that former-smokers who used e-cigarettes to quit smoking would offer to smokers who are considering using an e-cigarette to support an attempt to quit smoking. Vapers advised smokers to find the right combination of device, flavours and nicotine strength, continue to smoke and vape for a while if they wished, not be deterred by past failed attempts to quit smoking, and expect health to improve after they have switched to vaping. Encouraging smokers to interact with vaping peers in vape shops and in online vaping-dedicated discussion fora may help significantly more smokers switch to vaping.

2019

Association Between Electronic Cigarette Use and Smoking Reduction in France

Ramchandar Gomajee, Fabienne El-Khoury, Marcel Goldberg, Marie Zins, Cédric Lemogne, Emmanuel Wiernik, Emeline Lequy-Flahault, Lucile Romanello, Isabelle Kousignian, Maria Melchior
Published online: 15 Jul 2019

Findings  This cohort study found that, among daily smokers in France, regular (daily) electronic cigarette use is associated with a significantly higher decrease in the number of cigarettes smoked per day as well as an increase in smoking cessation attempts. However, among former smokers, electronic cigarette use is associated with an increase in the rate of smoking relapse.

NOTE: Article that covers above study – Adults who vape are more likely to quit cigarettes, study finds

“The study did find that the heightened risk of relapse disappeared in those who quit smoking more recently, which the researchers said may be due to improved e-cigarette technology.”

“For example, the study as a whole considered anybody who quit smoking from 2010 onward and found that, in that sample, vaping increased the risk of relapse. But when researchers only considered people who quit cigarettes as of 2013, former smokers were not more likely to relapse if they vaped.”

“The researchers noted in their study that “measures of plasma nicotine levels have shown that, compared with older models of [e-cigarettes], the new generation delivers higher levels of nicotine to the bloodstream,” which may make them more satisfying.”

“Other “technical improvements in [e-cigarettes] over time,” they said, may also explain why people who recently quit smoking and switched to e-cigarettes were less likely to relapse than those who quit earlier.”

Association of prevalence of electronic cigarette use with smoking cessation and cigarette consumption in England: a time–series analysis between 2006 and 2017

Emma Beard, Robert West, Susan Michie, Jamie Brown
Published online: 16 Oct 2019

The increase in prevalence of e‐cigarette use by smokers in England has been positively associated with an increase in success rates of quit attempts and overall quit rates

Electronic Cigarette Use and Cigarette Abstinence Over 2 Years Among U.S. Smokers in the Population Assessment of Tobacco and Health Study

Sara Kalkhoran, Yuchiao Chang, Nancy A Rigotti
Published online: 11 Jul 2019

In this nationally representative longitudinal cohort study of US adult cigarette smokers, daily e-cigarette use, compared to no e-cigarette use, was associated with a 77% increased odds of prolonged cigarette smoking abstinence over the subsequent 2 years. Regular use of e-cigarettes may help some smokers to stop smoking combustible cigarettes.

2020

Tobacco harm reduction in the 21st century

Renée O'Leary , Riccardo Polosa
Published online: 20 Sep 2020

In conclusion, to reduce smoking and to save millions of lives, tobacco harm reduction in the form of cigarette substitution with low-risk products appears to be a promising path. These products, although not completely risk-free, offer an alternative to quit or die. In consideration of the available evidence, advice to tobacco smokers should include trying substitute products. The obvious fact so often overlooked is that smoking is rewarding and people like to do it. Giving smokers an alternative with efficient nicotine delivery means that they might prefer one of these products over cigarettes. 

Highlights of Studies in Cardiovascular Disease Prevention Presented at the 2020 American College of Cardiology Annual Scientific Session

Xiaoming Jia, Mahmoud Al Rifai, Jing Liu, Anandita Agarwala, Martha Gulati, Salim S. Virani
Published online: 18 Jun 2020

In E3, nicotine e-cigarettes plus counselling was superior to counselling alone for smoking cessation. Non-nicotine e-cigarettes plus counselling was also more effective compared with counselling alone though its effects on cessation were modest. This trial demonstrates the efficacy of e-cigarettes as a tool for smoking cessation compared with counselling alone.

A Magic Bullet? The Potential Impact of E-Cigarettes on the Toll of Cigarette Smoking

David Mendez, Kenneth E Warner
Published online: 21 Aug 2020

The combination of assumptions produces 360 possible scenarios. 357 (99%) yield positive estimates of life-years saved (LYS) due to vaping by 2100, from 143,000 to 65 million. 

The impact of vaping is greatest when it most helps smokers who otherwise have the greatest difficulty quitting smoking.

Vaping is highly likely to reduce smoking-produced mortality. Still, vaping is not “the” answer to the public health crisis created by smoking. Rather, it may well be a tool to add to the armamentarium of effective tobacco control measures.

Harm reduction can, and many would say should, be a part of the complex formula that will eventually bring about the demise of smoking.

Patterns of E-cigarette Use and Subsequent Cigarette Smoking Cessation Over 2 Years (2013/2014–2015/2016) in the Population Assessment of Tobacco and Health Study

Allison M Glasser, Mahathi Vojjala, Jennifer Cantrell, David T Levy, Daniel P Giovenco, David Abrams, Raymond Niaura
Published online: 17 Sep 2020

Smoking cessation was more likely among frequent e-cigarette users, users of e-cigarettes in last quit attempt, and users of flavoured and rechargeable devices.

Using e-cigarettes for smoking cessation: evaluation of a pilot project in the North West of England

M Coffey, AM Cooper-Ryan, L Houston, K Thompson, PA Cook
Published online: 11 May 2020

Of the 1022 participants who engaged with the pilot 614 were still engaged at 4 weeks, of whom 62% had quit smoking. Of those who still smoked tobacco at week 4, smoking had reduced from a baseline of 19.1 cigarettes/day to 8.7. Overall, 37% of those initially enrolled were confirmed to be using an e-cigarette on its own at follow-up. Successful quit was associated with occupation (unemployed, 33% vs intermediate, 47%) and residing in the less deprived quintiles of deprivation (50% vs 34% in the most deprived quintile.

E-cigarettes appear to be an effective nicotine replacement therapy