Citation

Kasza, K.A., Hammond, D., Gravely, S., O’Connor, R.J., Meng, G., East, K.A., Borland, R., Cummings, K.M., Fong, G.T., Hyland, A. (2023). Associations between nicotine vaping uptake and cigarette smoking cessation vary by smokers’ plans to quit: Longitudinal findings from the International Tobacco Control (ITC) Four Country Smoking and Vaping Surveys. Addiction, 118(2), 340-352.

Abstract

Background and aims: Most population studies that evaluate the relationship between nicotine vaping and cigarette cessation focus on limited segments of the smoker population. We evaluated vaping uptake and smoking cessation considering differences in smokers' plans to quit.

Design: Longitudinal ITC Four Country Smoking and Vaping Surveys conducted in 2016, 2018, and 2020. Setting: US, Canada, England, Australia.

Participants: Adult daily cigarette smokers who had not vaped in the past 6 months at baseline and had participated in two or more consecutive waves of the ITC Four Country Smoking and Vaping Surveys (n= 2,815).

Measurements: Plans to quit cigarette smoking at baseline (within 6 months, beyond 6 months, not planning to quit) and at follow-up (within 6 months versus not within 6 months); cigarette smoking cessation at follow-up (smoking less than monthly [including complete cessation] versus daily/weekly/monthly smoking); inter-wave vaping uptake (none, only nondaily vaping, any daily vaping). Generalized estimating equations were used to evaluate whether inter-wave vaping uptake was associated with smoking cessation at follow-up, and with planning to quit at follow-up, each stratified by plans to quit smoking at baseline.

Findings: Overall, 12.7% of smokers quit smoking. Smokers not initially planning to quit within 6 months experienced higher odds of smoking cessation when they took up daily vaping (32.4%) versus no vaping (6.8%; adjusted odds ratio [AOR]=8.58, 95% confidence interval [CI]:5.06-14.54). Among smokers planning to quit, smoking cessation rates were similar between those who did and did not take up daily vaping (25.1% vs. 16.8%; AOR=1.91, 95%CI:0.91-4.00), though we could not account for potential use of cessation aids. Daily vaping uptake was associated with planning to quit smoking at follow-up among those initially not planning to quit (AOR=6.32, 95%CI:4.17-9.59).

Conclusions: Uptake of nicotine vaping appears to be strongly associated with cigarette smoking cessation among smokers with no initial plans to quit smoking. Excluding smokers not planning to quit from studies on vaping and smoking cessation may underestimate potential benefit of daily vaping for daily smokers.

Citation

Fix, B.V., O’Connor, R.J., Goniewicz, M.L., Leigh, N.J., Cummings, K.M., Hitchman, S.C., Fong, G.T., Nahhas, G.J., Hammond, D., McNeill, A., Borland, R., King, B., Palumbo, M. (2023). Characterisation of vaping liquids used in vaping devices across four countries: Results from an analysis of selected vaping liquids reported by users in the 2016 ITC Four Country Smoking and Vaping Survey. Tobacco Control, 32(1), 51-59.

Abstract

Objectives: This study presents an analysis of vaping products (VPs) purchased in the USA, Canada, England and Australia and assesses whether differences in regulations were associated with differences in the chemical composition of the VPs.

Methods: April-September 2017, a total of 234 VP refill liquids and prefilled cartridges were purchased in convenience samples of retail locations in each country. Products were chosen from brands and styles most commonly reported by current VP users in the 2016 ITC Four Country Smoking and Vaping Survey. All products were tested for nicotine, tobacco-specific nitrosamines (TSNAs), minor tobacco alkaloids, organic acids and flavouring chemicals.

Results: Consistent with the laws in Canada and Australia at the time of product purchase, nicotine was not detected in any of the VPs (n=10 in Canada; n=15 in Australia). US liquids (n=54) had a mean nicotine concentration of 16.2 mg/mL, (range=0.0-58.6) and English liquids (n=166) had a mean concentration of 11.9 mg/mL ((range=0.0-31.2) F(3244)=12.32, p<0.001). About 5% of English samples exceeded the UK's 20 mg/mL nicotine limit. Substantial country differences were observed in levels ofTSNAs, with the USA being higher than elsewhere. Of all products tested, 18.8% contained at least one organic acid. Liquids purchased in England contained far more identifiable flavouring chemicals than those in the other countries.

Conclusions: VP composition, particularly with respect to nicotine and flavouring, varies by country, likely reflecting both marketplace preferences and country-specific regulations. There are differences between nicotine levels claimed on the package and actual levels, particularly in England.

Citation

Cheng, K-W., Liu, G., Pesko, M., Levy, D.T., Fong, G.T., Cummings, K.M. (2023). Impact of vaping restrictions in public places on smoking and vaping in the US: Evidence using a difference-in-differences approach. Addiction, 118(1), 160-166.

Abstract

Aims: To estimate whether and to what extent extending indoor smoking restrictions to include electronic cigarettes (ECs) impact the use of ECs and cigarette smoking among adults in the US. Design: Observational study using a linear probability model and applying a difference-in-differences analysis SETTING: USA PARTICIPANTS: People aged 18 to 54 who lived in US counties where comprehensive indoor smoking laws in bars, restaurants, and private workplaces have been in place prior to 2010 (N = 45,111 for EC use analysis, N = 75,959 for cigarette use analysis). Measurements: Data on cigarette smoking, use of ECs, and place of residence from the Tobacco Use Supplement of the Current Population Survey (TUS-CPS 2010-2011, 2014-2015, and 2018-2019) were combined with the American Nonsmokers' Rights Foundation (ANRF) database of state and local indoor smoking and vaping restriction laws. Findings: Indoor vaping restriction (IVR) coverage was not significantly associated with the likelihood of adult EC use (coefficient estimate = 0.001; 95% confidence interval [CI] =-0.009, 0.013, P-value = 0.783). In addition, IVR coverage was not significantly associated with adult cigarette smoking (coefficient estimate = -0.00; 95% CI = -0.016, 0.015, P-value = 0.954). The non-significant results appeared in different socio-demographic subgroups. Conclusions: Indoor vaping restrictions do not appear to decrease electronic cigarette use among US adults. There is no evidence that indoor vaping restrictions increase or decrease cigarette smoking among US adults.

Citation

Hammond, D., Reid, J., Burkhalter, R., O’Connor, R.J., Goniewicz, M.L., Wackowski, O.A., Thrasher, J.F., Hitchman, S.C. (2023). Trends in e-cigarette brands, devices and the nicotine profile of products used by youth in England, Canada and the USA: 2017-2019. Tobacco Control, 32(1), 19-29. doi: 10.1136/tobaccocontrol-2020-056371

Abstract

Background: The e-cigarette market has rapidly evolved, with a shift towards higher nicotine concentration and salt-based products, such as JUUL; however, the implications for youth vaping remain unclear.

Methods: Repeat cross-sectional online surveys were conducted in 2017, 2018 and 2019, with national samples of youth aged 16–19 years recruited from commercial panels in Canada (n=12 018), England (n=11 362) and the USA (n=12 110). Regression models examined differences between countries and over time in the types of e-cigarette products used (design and nicotine content), reasons for using brands and differences in patterns of use, sociodemographics and dependence symptoms by brand/nicotine content.

Results: In 2019, the use of pod- or cartridge-style e-cigarettes was greater in Canada and the USA than England, with Smok and JUUL the leading brands in all countries. In 2019, youth vapers in England were less likely to report using e-cigarettes with ≥2% nicotine (12.8%) compared with Canada (40.5%; adjusted OR (AOR)=4.96; 95% CI 3.51 to 7.01) and the USA (37.0%; AOR=3.99, 95% CI 2.79 to 5.71) and less likely to report using nicotine salt-based products (12.3%) compared with Canada (27.1%; AOR=2.77, 95% CI 1.93 to 3.99) and the USA (21.9%; AOR=2.00, 95% CI 1.36 to 2.95). In 2019, self-reported use of products with higher nicotine concentration was associated with significantly greater frequency of vaping, urges to vape and perceived vaping addiction (p<0.05 for all).

Conclusions: The use of high-nicotine salt-based products is associated with greater symptoms of dependence, including JUUL and other higher-nicotine brands. Greater use of high-nicotine salt-based products may account for recent increases in the frequency of vaping among youth in Canada and the USA.

Citation

Li, L., Borland, R., Cummings, K.M., Fong, G.T., Hyland, A., Le Grande, M., McNeill, A. (2023). Non-cigarette combustible tobacco use and its associations with subsequent cessation of smoking among daily cigarette smokers: Findings from the International Tobacco Control Four Country Smoking and Vaping Surveys (2016-2020). Addiction, 118(1), 140-148. doi: 10.1111/add.16023.

Abstract

Aims: To examine whether poly-use of cigarettes and other smoked products (poly-smoking) is predictive of quit attempts and quit success.

Design: A prospective multi-country cohort design.

Setting: Australia, Canada, England and the US.

Participants: 3983 adult daily cigarette smokers were surveyed in 2016 (Wave 1 of data collection) and were recontacted in 2018 (Wave 2) (i.e., Wave 1–Wave 2 cohort) in the International Tobacco Control Four Country Smoking and Vaping (ITC 4CV) Surveys; and 3736 smokers were surveyed in 2018 and recontacted in 2020 (Wave 3) (i.e., Wave 2–Wave 3 cohort).

Measurements: Participants were asked about their cigarette smoking and use of cigars, cigarillos, pipes, and waterpipes. Outcomes were quit attempts between two survey waves and success, defined as having quit smoking all the combustible tobacco at the subsequent survey for 1 month or more.

Findings: Levels of poly-smoking were 12.7% in the Wave 1–Wave 2 cohort and 10.5% for the Wave 2–Wave 3 cohort. Compared with cigarette-only smokers, poly-smokers were more likely to attempt between Waves 1 and 2 (54.9% vs. 42.7%, adjusted odds ratio (aOR)=1.37, 95% confidence interval [CI] 1.08-1.74, p<0.01), but not between Waves 2 and 3 (43.8% vs. 40.1%, aOR=0.94, 95%CI 0.72-1.22). Poly-smoking predicted reduced likelihood of success in both cohorts among attempters and the overall samples. Between Waves 2 and 3 there were significantly more transitions to non-daily smoking among the poly-smokers (12.4% vs. 5.3%, 2=40.4, p<0.001).

Conclusions: There is a consistent association between poly-smoking (use of cigarettes along with other smoked products) and reduced quit success for combustible tobacco, but it is likely due to increased likelihood of transitioning to non-daily use rather than complete cessation.

Citation

Gravely, S., Driezen, P., McClure, E., Hammond, D., Cummings, K.M., Chan, G.C.K., Hyland, A., Borland, R., East, K., Fong, G.T., Schauer, G.L., Quah, A.C.K., Ouimet, J., Smith, D.M. (2022). Differences between adults who smoke cigarettes daily and do and do not co-use cannabis: Findings from the 2020 ITC Four Country Smoking and Vaping Survey. Addictive Behaviours, 135, 107434. doi: 10.1016/j.addbeh.2022.107434.

Abstract

Background: Little is known about population-level differences between adults who exclusively smoke cigarettes and those who smoke cigarettes and also use cannabis (co-consumers). Thus, this study describes differences on sociodemographic, cigarette-dependence, health and behavioral variables, and risk perceptions associated with smoking cannabis.

Methods: This cross-sectional study included 6941 respondents from the 2020 ITC Four Country Smoking and Vaping Survey (US, Canada, Australia, England). Adult daily cigarette smokers were included and categorized as: cigarette-only smokers (never used cannabis/previously used cannabis, but not in the past 12 months, n=4857); occasional co-consumers (cannabis use in the past 12 months, but<weekly use, n=739); or regular co-consumers (use cannabis ≥weekly, n=1345). All outcomes were self-reported. Regression models were conducted on weighted data.

Results: Overall, 19.9% of respondents reported regular cannabis co-use and 10.1% reported occasional co-use. Regular co-use was highest in Canada (27.2%), followed by the US (24.4%), England (12.7%) and Australia (12.3%). Compared to cigarette-only smokers, regular co-consumers were more likely to be male and report chest/breathing problems (p<0.001). All co-consumers were more likely to be younger, have lower income, be experiencing financial stress, reside in Canada, have depressive symptoms, use alcohol more frequently and binge drink, use other tobacco/nicotine products, and perceive smoking cannabis as low health risk and less harmful than smoking cigarettes (all p><0.001). Cigarette dependence measures were similar between co-consumers and cigarette-only smokers (all p≥0.05).

Conclusions: Although there were no differences on cigarette dependence measures between daily cigarette smokers who do and do not use cannabis, there are several other risk factors that may affect tobacco use and abstinence among co-consumers (e.g., greater depression, high-risk alcohol consumption). Thus, tobacco cessation treatment may require multi-pronged strategies to address other health behaviors. Continued surveillance is needed to determine the nature and health implications of co-use considering changing policies, markets, and products.

Citation

Gravely, S., Meng, G., Hammond, D., Reid, J., Hyland, A., Cummings, K.M., Rivard, C., Fong, G.T., Seo, Y., Kasza, K.A. (2022). Electronic nicotine delivery systems (ENDS) flavors and devices used by adults before and after the 2020 US FDA ENDS enforcement priority: Findings from the 2018 and 2020 US ITC Smoking and Vaping Surveys. Tobacco Control, 31 (Suppl3), s167-s175.

Abstract

Background: In February 2020, the US Food and Drug Administration (FDA) prioritised enforcement efforts against flavoured prefilled cartridge/pod electronic nicotine delivery systems (ENDS), with the exception of tobacco and menthol. This study examined changes between prepriority enforcement (2018) and early postenforcement (February-June 2020) among adults on: ENDS flavours and devices used most often; location of last purchase of fruit/other-flavoured cartridges (covered under the enforcement priority); and smoking and vaping.

Methods: Prevalence estimates came from 1608 adult frequent (≥weekly) ENDS users (current smokers (n=1072), ex-smokers (n=536)) who participated in the 2018 and/or 2020 US ITC Smoking and Vaping Surveys. Transitions between flavours/devices and changes in smoking/vaping were assessed among baseline respondents who were followed up in 2020 (n=360). Respondents self-reported the ENDS device (disposable, cartridge/pod or tank) and the flavor that they used most often: (1) tobacco flavors (tobacco/tobacco-menthol mix) or unflavored; (2) menthol/mint; (3) fruit/other flavors.

Results: Compared to 2018, in the first 5 months of the 2020 enforcement priority, there were significant increases in the prevalence of fruit/other-flavoured cartridges (7.9% to 12.4%, p=0.026) and menthol/mint cartridges (7.1% to 13.0%, p<0.01) and decreases in tobacco-flavoured tanks (15.5% to 10.0%, p=0.002) and fruit/other-flavoured tanks (38.7% to 33.6%, p=0.038). Fewer than 10% of adults used disposables in 2018 and 2020. Among the cohort sample, the most pronounced transitions between flavours/devices occurred among those who used flavoured cartridges covered under the enforcement priority (54.6% switched to a flavour and/or device excluded from enforcement). There was an increase in purchasing fruit/other-flavoured cartridges online and a decrease in retail locations except for vape shops. Overall, there were few changes in smoking and vaping behaviours.

Conclusions: Between 2018 and the early phase of the FDA's 2020 enforcement priority, prevalence of menthol/mint and fruit/other-flavoured cartridges increased among adults. Half of vapers using cartridge flavours covered in the enforcement switched to other flavours and/or devices that were exempt, with the exception of disposables. The extent to which more comprehensive restrictions may be problematic for adults who prefer a range of ENDS flavours remains uncertain.

Citation

Freitas Lemos, R., Stein, J.S., Tegge, A.N., Kaplan, B.A., Heckman, B.W., McNeill, A., Cummings, K.M., Fong, G.T., Bickel, W.K. (2022). The Illegal Experimental Tobacco Marketplace II: Effects of vaping product bans - findings from the 2020 International Tobacco Control Project. Tobacco Control, 31(Suppl 3), s214-s222.

Abstract

Significance: Restrictive e-cigarette policies may increase purchases from illegal sources. The Illegal Experimental Tobacco Marketplace (IETM) allows examination of how restrictions impact illegal purchases. We investigated (1) the effect of a vaping ban, total flavour vaping ban and partial flavour vaping ban on the probability of purchasing illegal vaping products among different regulatory environments (USA, Canada and England) and tobacco user types (cigarette smokers, dual users and e-cigarette users); and (2) the relation between ban endorsement and illegal purchases.

Methods: Participants (N=459) from the International Tobacco Control Survey rated their support of bans and chose to purchase from a hypothetical legal experimental tobacco marketplace or IETM under control and the three ban conditions.

Results: In total, 25% of cigarette smokers, 67% of dual users and 79% of e-cigarette users made IETM purchases. Cross-country comparisons depicted dual users from Canada (OR: 19.8), and e-cigarette users from the USA (OR: 12.9) exhibited higher illegal purchases odds than the same user type in England. Within-country comparisons showed e-cigarette and dual users are more likely to purchase from the IETM than cigarette smokers in the most restrictive condition, with the largest effects in e-cigarette users (England-OR: 1722.6, USA-OR: 22725.3, Canada-OR: 6125.0). Increased opposition towards partial or total flavour ban was associated with increased IETM purchasing in the corresponding condition.

Conclusions: Vaping restrictions may shift users' preference to the illegal marketplace in a regulatory environment. Evidence of the IETM generalisability in a geographically dispersed sample enhances its utility in tobacco regulatory science.

Citation

Schneller, L., Kasza, K, Hammond, D., Bansal-Travers, M., O’Connor, R.J., Hyland, A. (2022). E-cigarette and tobacco product use among NYS youth before and after a state-wide vaping flavour restriction policy, 2020-2021. Tobacco Control, 31 (Suppl3), s161-s166.

Abstract

Significance: Reducing youth e-cigarette use is a New York State (NYS) public health priority. In May 2020, a state-wide restriction on flavoured e-cigarettes, except tobacco flavour, was passed. This study examines changes in nicotine product use behaviour among youth around the time of the state-wide vaping flavour restriction.

Methods: NYS data from the US International Tobacco Control Policy Evaluation Project Youth Tobacco and E-cigarette Tobacco and Vaping Survey were analysed cross-sectionally from February 2020 (n=955), August 2020 (n=946), February 2021 (n=1030), and August 2021 (n=753). Online surveys were conducted among youth 16–19 years. Weighted descriptive statistics and regression models were used to describe changes in nicotine product use behaviour. Models were adjusted for age, sex, race/ethnicity and perceived family socioeconomic status.

Results: Significant decreases in past 30-day e-cigarette use (20%–11%), cigarette (7%-4%), and dual use of e-cigarettes and cigarettes (5%–2%) were observed over the 2-year period in NYS. Over 95% of vapers still reported using a non-tobacco-flavoured e-cigarette following the restriction, with fruit-flavoured being the most popular at each time point.

Conclusions: Nearly all NYS youth continued to vape flavours that were restricted in NYS. While youth past 30-day vaping prevalence decreased significantly from 2020 to 2021, increased flavour restriction compliance could result in an even greater decrease. Continuous monitoring is important to better understand perceptions, use patterns and access at the individual level, retail level and population level to inform future enforcement and restrictions.

Citation

Le Grande, M., Balmford, J., Borland, R., McNeill, A. (2022). Perceived health and capacity to cope with stress in recent ex-smokers: Impact of vaping vs quitting all nicotine. Nicotine and Tobacco Research, [Published online November 1, doi: 10.1093/ntr/ntac252].

Abstract

Background: Little is known about the continued use of nicotine following smoking cessation on perceived well-being in comparison to complete cessation of nicotine use. Aims: To explore aspects of perceived well-being and coping among recent ex-smokers as a function of vaping status.

Methods: Ever-daily smokers in the International Tobacco Control 4 country smoking and vaping surveys in 2016 (W1 N=883) and 2018 (W2 N=1088). Cross-sectional associations and longitudinal samples for those who quit between waves and those quit at W1 who maintained abstinence to W2.

Main outcome measures were: past 30 days depression symptoms, perceived stress, stress management since quitting and change in perceived day-to-day health.

Results: In the cross-sectional analyses vapers were more likely to report both improved stress management (aOR = 1.71, 95% CI 1.23-2.36) and perceived day-to-day health (aOR = 1.65, 95% CI 1.26-2.16) than nicotine abstainers. In the longitudinal analyses, smokers who switched to vaping between waves (n=372) were more likely to report depression symptoms at W2 (aOR = 2.00, 95% CI 1.09-3.65) but reported improved perceived health (aOR = 1.92, 95% CI 1.16-3.20). For the past daily smokers who remained quit between waves (n=382), vapers were more likely to report improved stress management relative to abstainers (RRR =5.05. 95% CI 1.19-21.40). There were no other significant differences between vapers and nicotine abstainers.

Conclusions: There is little evidence to support the view that perceptions of well-being deteriorate in vapers compared to complete nicotine abstainers in the immediate years after smoking cessation.

Implications: This study could find no conclusive evidence that the continued use of nicotine via e-cigarettes was detrimental to health compared to completely stopping nicotine intake altogether. Our results would suggest that continuing to use nicotine may even result in some benefits in the short term such as improved stress management, however further longitudinal studies are required to examine if these effects are restricted to the early post-quitting phase and whether other positive or negative effects on psychosocial health emerge in the future.

Citation

Gravely, S., Yong, H.H., Reid, J., East, K.A., Gartner, C., Levy, D.T., Cummings, K.M., Borland, R., Quah, A.C.K., Bansal-Travers, M., Ouimet, J., Fong, G.T. (2022). Do current smokers and ex-smokers who use nicotine vaping products daily versus weekly differ on their reasons for vaping? Findings from the ITC Four Country Smoking and Vaping Survey. International Journal of Environmental Research and Public Health, 19(21), 14130. doi: 10.3390/ijerph192114130.

Abstract

This study examined reasons why adults who currently smoke or formerly smoked cigarettes use nicotine vaping products (NVPs) by vaping frequency (daily vs. weekly) stratified by smoking status.

This crosssectional study included 3070 adults from the 2020 ITC Four Country Smoking and Vaping Survey (Australia, Canada, England, United States) who reported using a NVP (vaping) at least weekly and who either currently smoke (n = 2467) or formerly smoked (n = 603). Respondents were asked to select the reason(s) they use NVPs, including to manage their smoking (reduce/quit or remain quit) and/or for reasons unrelated to managing smoking (e.g., to save money, enjoyment, flavours).

We found that both current and former smokers endorsed an average of six reasons for vaping, with those vaping daily reporting significantly more reasons than those vaping weekly. Among current smokers, 72.8% reported vaping may help them quit smoking, 13.0% reported vaping to reduce smoking but not to quit, and 14.2% reported vaping only for reasons other than to reduce or quit smoking. The most common reason for vaping among current smokers was to reduce smoking (81.3%). Current smokers vaping daily were significantly more likely than those vaping weekly to report using a NVP to reduce smoking, for enjoyment, to reduce harm to themselves and others, to quit smoking, likeable flavours, and to save money. The most common reason cited for vaping by respondents who formerly smoked was enjoyment, with those who vaped daily more likely than those who vaped weekly to report vaping for enjoyment and to reduce harm to themselves. Nearly all reported vaping to help stay abstinent from smoking (92.3%), with no significant difference by vaping frequency.

In conclusion, a majority of respondents reported using NVPs to manage their smoking (reduce/quit smoking or remain quit), particularly those vaping daily. Those who were vaping daily also endorsed a greater number of reasons other than managing smoking relative to those who were vaping weekly.

Citation

Craig, L., Chung-Hall, J., Meng, G., Fong, G.T. (2022). Calculating the potential environmental impact of a menthol cigarette ban in the United States. Tobacco Control, [Published online October 13, doi: 10.1136/tc-2022-057563].

Infographics: Oct 2022 | Calculating the Potential Environmental Impact of a Menthol Cigarette Ban in the USA

Press Release: Oct 13, 2022 | Proposed menthol ban in U.S. would cut littering by 3.8 billion cigarettes butts annually

Media & Related Documents:

Nov 7, 2022 | The environmental argument for banning menthol cigarettes - Popular Science, Carla Delgado

Nov 7, 2022 | Craig, L.V., & Fong, G.T. (2022). Answers to questions about the impact of a proposed US menthol cigarette ban on reducing cigarette litter. Sent to Carla Delgado, Popular Science.

Citation

Usidame, O., Meng, G., Thrasher, J.F., Thompson, M.E., Fong, G.T., Fleischer, N.L. (2022). Examining the effectiveness of the 2012 Canadian graphic warning label policy change by sex, income, and education. Nicotine and Tobacco Research, [Published online, doi: 10.1093/ntr/ntac235].

Abstract

Background: We examined the differential impact of the 2012 Canadian GWL policy changes on key indicators of warning label impact and quit intentions using national cohorts of Canadian and US adults who smoke.

Methods: We used data from all waves of the International Tobacco Control surveys (2002-2020) in Canada and the US. Our key measures were quit intentions and an index of warning label effectiveness (salience, cognitive and behavioral reactions). We estimated overall policy impact by comparing Canada (treatment group) with the US (control group) using controlled interrupted time series (CITS) regression models, with interactions to examine whether policy impact varied by sex, education, and income.

Results: The CITS model showed a statistically significant increase in the warning label effectiveness in Canada post-policy, compared to the US (β= 0.84, 95% CI 0.35,1.33). Similarly, the odds of quit intentions were relatively higher among adults who smoked in Canada compared to the US (OR= 1.89, 95% CI 1.51,2.36) post-policy. The three-way interaction model showed that these associations were greater among adults from low socioeconomic status (SES) groups than in high SES groups.

Discussion: The 2012 change in the Canadian GWL policy was associated with stronger cognitive and behavioral responses to GWLs and higher odds of quit intentions among adults who smoked in Canada when compared to the US, specifically among individuals from low SES groups, suggesting a positive equity impact. Our findings affirm the need for countries to implement or enhance GWLs, in line with the WHO Framework Convention on Tobacco Control.

Implications: The evidence on the potential health equity benefit of GWL policies is mixed. To further understand the influence of GWL policies on tobacco use disparities, more systematic research using pre/post policy designs with control groups is needed. Using a controlled interrupted time series model, we aimed to strengthen the available evidence on the causal influence of this tobacco control approach. Our findings show that the 2012 GWL policy change had a greater impact on adults who smoked from low SES groups than it did on adults who smoked from high SES groups, indicating a potentially positive equity impact and confirming the need for countries to implement or maximize the size of GWLs, as recommended by the WHO Framework Convention on Tobacco Control.

Citation

Yong, H.H., Chow, R., East, K.A., Thrasher, J.F., Hitchman, S.C., Borland, R., Cummings, K.M., Fong, G.T. (2022). Do social norms for cigarette smoking and nicotine vaping product use predict trying nicotine vaping products and attempts to quit cigarette smoking amongst adult smokers? Findings from the 2016-2020 ITC Four Country Smoking and Vaping Surveys. Nicotine and Tobacco Research, [Published online, doi:https://doi.org/10.1093/ntr/ntac212].

Abstract

Objectives: To examine whether perceived injunctive and descriptive social norms towards cigarette and nicotine vaping product (NVP) use predicted subsequent trying NVPs and attempts to quit cigarette smoking amongst current smokers, and whether associations varied across countries.

Method: Three waves of longitudinal cohort data from the International Tobacco Control Four Country Smoking and Vaping Survey collected between 2016 and 2020 from 2,290 adult smokers in Canada, Australia, England, and the United States who had never used NVPs at baseline (either Wave 1 or Wave 2) and followed up at the subsequent wave (Wave 2 or Wave 3, respectively) were analysed using Generalised Estimating Equations.

Results: Of the injunctive and descriptive norm measures for smoking and NVP use, NVP initiation was only independently predicted by the injunctive interpersonal norm for NVP use, with perceived approval of NVP use by important others predicting higher odds of trying NVPs (AOR=1.65, 95% CI=1.20-2.27). This predictive effect was independent of baseline quit intention with no country variations found. By contrast, making cigarette smoking quit attempts was independently predicted by both injunctive and descriptive interpersonal norms with perceived disapproval of smoking by important others (AOR=1.65, 95% CI=1.38-1.99) and close friends using NVPs (AOR=1.37, 95% CI=1.04-1.79), both associated with higher odds of smoking quit attempts.

Conclusions: Adult smokers who perceive NVP use as normative, either because such behaviour is socially approved or common within their close social networks, appear more inclined to try NVPs or make smoking quit attempts than smokers who do not.

Implications: What this study adds: Social norms can shape a person's behaviour and result in behaviour change. This study shows that initiation of NVP use behaviour among smokers can be reliably predicted by their perception of whether NVP use is acceptable to those important to them within their close social networks. Similarly, any attempts to stop cigarette smoking can be predicted by their perception of how acceptable cigarette smoking is among those who are important to them and whether any of their close friends use NVPs. Changing social norms towards cigarette smoking and NVP use could therefore be incorporated into smoking cessation interventions to help smokers to quit and/or switch to NVP use.

Citation

Gravely, S., Meng, G., Hammond, D., Hyland, A., Cummings, K.M., Borland, R., Kasza, K., Yong, H.H., Thompson, M.E., Quah, A.C.K., Ouimet, J., Martin, N., O’Connor, R.J., East, K.A., McNeill, A., Boudreau, C., Levy, D.T., Sweanor, D.T., Fong, G.T. (2022). Differences in cigarette smoking quit attempts and cessation between adults who did and did not take up nicotine vaping: Findings from the ITC Four Country Smoking and Vaping Surveys. Addictive Behaviors, 132, 107339.

Abstract

Introduction: There is mixed evidence as to whether nicotine vaping products (NVPs) can help adults who smoke transition away from cigarettes. This study investigated if rates of self-reported attempts to quit smoking and smoking cessation over a period of either 18 or 24 months differed between respondents who initiated nicotine vaping versus those who did not. Outcome comparisons were made between those who: (1) initiated vaping vs. those who did not; (2) initiated daily or non-daily vaping vs. those who did not; and (3) initiated daily or non-daily vaping between surveys and continued to vape at follow-up (daily or non-daily) vs. those who did not initiate vaping.

Methods: This cohort study included 3516 respondents from the ITC Four Country Smoking and Vaping Surveys (Australia, Canada, England, US), recruited at Wave 1 (2016) or 2 (2018) and followed up at Wave 2 (12 months) and/or 3 (2020, 24 months). Adults who smoked daily at baseline and did not have a history of regular vaping were included. Initiation of vaping was defined as beginning to vape at least monthly between surveys. Respondents indicated whether they made an attempt to quit smoking between surveys. Smoking cessation was defined as those who self-reported no longer smoking cigarettes at follow-up.

Results: Relative to those who did not initiate vaping, any daily vaping was associated with a greater likelihood of smokers making a cigarette quit attempt (p<0.001) and quitting smoking (p<0.001). Among smokers who attempted to quit smoking, any daily vaping was associated with a greater likelihood of being abstinent from smoking at follow-up (p=0.001). Respondents who initiated vaping between surveys and were vaping daily at follow up were significantly more likely to have attempted to quit smoking (p<0.001) and to have quit smoking (p<0.001) than those who did not initiate vaping. Respondents who initiated non-daily vaping did not differ significantly from those who did not initiate vaping on any of the outcome measures.

Conclusions: Daily NVP use was associated with increased attempts to quit smoking and abstinence from smoking cigarettes. These findings are consistent with the concept that complete cigarette substitution may be more likely to be achieved when smokers vape nicotine daily.

Citation

Li, L., Borland, R., Yong, H.H., Gravley, S., Fong, G.T., Cummings, K.M., East, K.A., Le Grande, M. (2022). Experienced effects on well-being following smoking cessation: Findings from the 2020 ITC Four Country Smoking and Vaping Survey. International Journal of Environmental Research and Public Health, 19(16), 10037. doi: 10.3390/ijerph191610037

Abstract

Background and Aims: There has been limited research addressing changes in subjective well-being as a result of quitting smoking. This paper examines recent ex-smokers’ well-being related experiences overall and as a function of (1) duration of cessation and (2) continued nicotine use from vaping.

Methods: A sample of 1379 ever-daily smoking ex-smokers (quit for up to 5 years) from the 2020 ITC Four Country Smoking and Vaping Survey (Australia, Canada, the UK, and the US), of which 27.1% currently vaped daily. Well-being measures were perceived changes post-quitting in emotion coping (stress and negative emotions), enjoyment of life, and day-to-day functioning. We also assessed the level of persisting worry about past smoking leading to future health problems.

Results: Overall, among those answering all four well-being measures, 51.8% of the ex-smokers reported positive effects and no negatives, but 27.3% reported at least one negative effect, with the remainder reporting no change in any measure. Positive effects were greater among those who had quit more than 1 year prior. The largest improvement (56.3%) was for daily functioning, which showed improvement over time since having quit. Current daily vapers reported similar well-being as those not vaping; however, fewer daily vapers reported worsening ability to cope with stress (10.2% vs. 20.7%). Overall, 84% reported being worried about future negative health effects of smoking, with no clear differences by quitting duration or vaping status.

Conclusions: Most ex-smokers reported changes in their well-being since quitting, with more reporting improvements than declines. Well-being improved with duration of time since quitting, but did not appear to be influenced by daily vaping use, but stress coping may be better among vapers. Persisting worries about possible future health effects from smoking may be reducing the experienced benefits of quitting smoking for some.

Citation

Yong, H.H., Gravely, S., Borland, R., Gartner, C., Cummings, K.M., East, K., Tagliaferri, S., Elton-Marshall, T., Hyland, A., Bansal-Travers, M., Fong, G.T. (2022). Do smokers’ perceptions of the harmfulness of nicotine replacement therapy and nicotine vaping products as compared to cigarettes influence their use as an aid for smoking cessation? Findings from the ITC Four Country Smoking and Vaping Surveys. Nicotine & Tobacco Research, 24(9), 1413-1421. doi: 10.1093/ntr/ntac087.

Abstract

Aim: This study examined whether smokers' harm perceptions of nicotine replacement therapy (NRT) and nicotine vaping products (NVPs) relative to cigarettes predicted their subsequent use as smoking cessation aids during their last quit attempt (LQA).

Methods: We analyzed data from 1,315 current daily smokers (10+ cigarettes per day) who were recruited at Wave 1 (2016), and who reported making a quit attempt by Wave 2 (2018) of the International Tobacco Control Four Country Smoking and Vaping Surveys in Australia, Canada, England, and the US. We used multinomial logistic regression models to examine prospective associations between harm perceptions of a) NRT and b) NVPs and their use at LQA, controlling for socio-demographic and other potential confounders.

Results: Smokers who perceive that a) NRT and b) NVPs are much less harmful than cigarettes were more likely to subsequently use the respective product as an aid than using no aid or other aids during LQA (adjusted relative risk ratio [aRRR]=3.79, 95%CI=2.16-6.66; and aRRR=2.11, 95%CI=1.29-3.45, respectively) compared to smokers who perceive these products as equally or more harmful. Additionally, those who perceive NVPs as much less harmful than cigarettes were less likely to use NRT as a quit aid (aRRR=0.34, 95%CI=0.20-0.60). No country variations for these associations were found.

Conclusion: This study found that smokers' perceptions of the harmfulness of a) NRT and b) NVPs relative to cigarettes predicted the respective product use when trying to quit smoking. Corrective education targeting misperceptions of nicotine products' relative harmfulness may facilitate their use for smoking cessation.

Implications: What this study adds: Nicotine replacement therapy and nicotine vaping products are two commonly used smoking cessation aids. This study demonstrates that misperceptions of the harms of nicotine products relative to cigarettes influence their use for smoking cessation. Believing that nicotine vaping products are much less harmful than cigarette smoking may lead some smokers to prefer these products over nicotine replacement therapy to aid smoking cessation. Education targeting misperceptions of nicotine products' harmfulness relative to cigarettes may enable smokers to make informed choices about which are appropriate to aid smoking cessation.

Citation

Freitas Lemos, R., Tegge, A.N., Craft, W.H., Tomlinson, D.C., Stein, J., Bickel, W.K. (2022). Understanding data quality: Instructional comprehension as a practical metric in crowdsourced investigations of behavioural economic cigarette demand. Experimental and Clinical Psychopharmacology, 30(4),415-423.

Abstract

Crowdsourcing platforms allow researchers to quickly recruit and collect behavioral economic measures in substance-using populations, such as cigarette smokers. Despite the broad utility and flexibility, data quality issues have been an object of concern. In two separate studies recruiting cigarette smokers, we sought to investigate the association between a practical quality control measure (accuracy on an instruction quiz), on internal consistency of number of cigarettes smoked per day and purchasing patterns of tobacco products in an experimental tobacco marketplace (ETM; Study 1), and in a cigarette purchase task (CPT; Study 2). Participants (N = 312 in Study 1; N = 119 in Study 2) were recruited from Amazon mechanical turk. Both studies included task instructions, a quiz, a purchase task, cigarette usage and dependence questions, and demographics. The results show that participants who answered all instruction items correctly: (a) reported the number of cigarettes per day more consistently (partial η2 = 0.11, p < .001, Study 1; partial η2 = 0.09, p = .016, Study 2), (b) demonstrated increased model fit among the cigarette demand curves (partial η2 = 0.23, p < .001, Study 1; partial η2 = 0.08, p = .002, Study 2), and purchased tobacco products in the ETM more consistently with their current usage. We conclude that instruction quizzes before purchase tasks may be useful for researchers evaluating demand data. Instruction quizzes with multiple items may allow researchers to choose the level of data quality appropriate for their studies.

Citation

Felicione, N., Fix, B., McNeill, A., Cummings, K.M., Goniewicz, M.L., Hammond, D., Borland, R., Heckman, B.W., Bansal-Travers, M., Gravely, S., Hitchman, S.C., Levy, D.T., Fong, G.T., O’Connor, R.J. (2022). Characteristics and changes over time of nicotine vaping products used by participants in the 2016 and 2018 ITC Four Country Smoking and Vaping Surveys. Tobacco Control, 31(e1), e66-e73. doi: 10.1136/tobaccocontrol-2020-056239

Abstract

Objectives: Regulation of nicotine vaping products (NVPs) varies between countries, impacting the availability and use of these products. This study updated the analyses of O'Connor et al on types of NVPs used and examined changes in NVP features used over 18 months in four countries with differing regulatory environments.

Design: Data are from 4,734 adult current vapers in Australia, Canada, England, and the USA from Waves 1 (2016) and 2 (2018) of the International Tobacco Control Four Country Smoking and Vaping Survey. NVP characteristics included device description, adjustable voltage, nicotine content and tank size. Longitudinal analyses (n=1,058) assessed movement towards or away from more complex/modifiable NVPs. A logistic regression was used to examine factors associated with changes in device description from 2016 to 2018.

Results: Like 2016, box-tanks were the most popular NVP (37.3%) in all four countries in 2018. Over 80% of vapers continued using the same NVP and nicotine content between waves, though movement tended towards more complex/modifiable devices (14.4% of vapers). Box-tank users, exclusive daily vapers and older vapers were most likely to continue using the same device description. Certain NVPs and features differed by country, such as higher nicotine contents in the USA (11.5% use 21+ mg/mL) and greater device stability over time in Australia (90.8% stability).

Conclusions: Most vapers continued using the same vaping device and features over 18 months. Differences in NVP types and features were observed between countries, suggesting that differing NVP regulations affect consumer choices regarding the type of vaping device to use.

Citation

Cho, Y., Thrasher, J.F., Gravely, S., Alberg, A.J., Borland, R., Yong, H.H., Cummings, K.M., Hitchman, S.C., Fong, G.T. (2022). Adult smokers’ discussions about vaping with health professionals and subsequent behavior change: a cohort study. Addiction, 117(11), 2933-2942. doi: 10.1111/add.15994.

Abstract

Aims: To measure the prevalence and changes in smokers' discussions with health professionals (HPs) about nicotine vaping products (NVPs) and HPs' recommendations about NVPs between 2016 and 2020, and their associations with tobacco product use transitions.

Design: Cohort study using multinomial logistic regression analyses on data from Waves 1 (2016), 2 (2018), and 3 (2020) from the International Tobacco Control Four Country Smoking and Vaping Surveys.

Setting: Four countries with varying NVP regulatory environments: 'most restrictive' (Australia), 'somewhat restrictive' (Canada), and 'less restrictive' (England and the US).

Participants: Adult exclusive daily smokers who did not report NVP use at the time of their baseline survey and had visited a HP in the last 12-24 months. Prevalence data came from 4,125, 4,503, and 4,277 respondents respectively for each year. Longitudinal data were from 4,859 respondents who participated in at least two consecutive surveys.

Measurements: (1) Prevalence of self-reported discussions with HPs and recommendations from HPs about NVPs and (2) longitudinal transitions from smoking to vaping (either exclusively or concurrently with smoking) and quitting (regardless of NVP uptake).

Findings: The prevalence of NVP discussions was low across countries with varying regulatory environments and study waves (range=1.4%-6.2%). In 2020, a low percentage of smokers who discussed NVPs with a HP reported that their HPs recommended they use NVPs in the US (14.7%), Australia (20.2%), Canada (25.7%), with a higher percentage in England (55.7%) where clinical guidelines for smoking cessation include NVPs. Compared with 12.0% of smokers who reported no discussion, 37.0% of those whose HPs recommended NVPs transitioned to vaping at follow-up. Transition to quitting was 9.6% with HPs' recommendation of NVPs versus 13.5% without discussion, a non-significant difference.

Conclusions: In Australia, Canada, England, and the United States between 2016 and 2020, health professionals' discussions with smokers about nicotine vaping products (NVPs) were infrequent. NVP discussions were associated with NVP uptake, but not with quitting smoking.

Citation

Taylor, E., Aleyan, S., East, K., Cummings, K.M., Thrasher, J.F., Fong, G.T., Quah, A.C.K., Li, G., Borland, R., Hammond, D., Hitchman, S.C. (2022). Associations between noticing nicotine vaping product health warning labels, harm perceptions, and use among adult vapers, current and former smokers: Findings from the 2018 ITC Four Country Smoking and Vaping Survey. Nicotine and Tobacco Research, 24(7), 1020-1027.

Abstract

Background: The number of countries mandating a nicotine addiction warning label (‘warnings’) on nicotine vaping products (NVPs) has been increasing. This study examined associations between noticing NVP warnings, perceptions of NVPs, and intentions to use NVPs.

Methods: Cross-sectional analysis of 12,619 adult NVP users, cigarette smokers, concurrent users of both cigarettes and NVPs, and quitters who participated in the 2018 International Tobacco Control (ITC) Project Four Country Smoking and Vaping Survey (England, Australia, Canada, US). Logistic regression analyses examined associations between noticing warnings in the past 30 days and perceptions of nicotine harm, NVP harm relative to cigarettes, and NVP addictiveness relative to cigarettes. Associations were also explored between noticing warnings and intentions to use NVPs.

Results: Noticing warnings was higher among NVP users (18.8%) than non-users (2.1%). Noticing warnings was associated with perceiving nicotine to pose little or no harm to health among NVP users, but there was no association among non-users. There was little evidence of an association between noticing warnings and perceptions of NVP harms relative to smoking among NVP users and non-users. Noticing warnings was associated with perceiving NVPs as less addictive than cigarettes among non-users but not NVP users. Among exclusive smokers, noticing warnings was associated with intending to start using NVPs. Among NVP users, there was little evidence of an association between noticing warnings and intentions to continue using/stopping NVPs.

Conclusions: Noticing NVP warnings was not associated with increased NVP and nicotine harm perceptions or decreased intentions to use NVPs among adult smokers and vapers

Citation

Miller, C., Xu, S.S., Smith, D.M., Sutanto, E., Goniewicz, M.L., Quah, A.C.K., Fong, G.T. (2022). Assessing use of inhalable nicotine products within complex markets: The dilemma of heated tobacco products. Tobacco Control, [Published online, doi:10.1136/tobaccocontrol-2021-057081].

Abstract

The introduction of electronic inhalable products, such as nicotine vaping products (NVPs) and heated tobacco products (HTPs), has further diversified the nicotine market landscape. This poses unique challenges in measuring self-reported nicotine use behaviours, which have been the hallmark of tobacco surveillance systems. This paper raises concerns of potential measurement error for electronic inhalable product use in surveys due to similarities in product design between NVPs and HTPs, as well as changing trends in cannabis administration. We identify several strategies for addressing this issue (eg, including descriptive preambles in surveys that differentiate product classes from one another; incorporating survey questions that probe beyond an initial question regarding product use). In the absence of comprehensive validation studies, caution is warranted when interpreting survey results that rely on self-reported HTP use.

Citation

Felicione, N., Schneller, L., Goniewicz, M.L., Hyland, A., Cummings, K.M., Bansal-Travers, M., Fong, G.T., O’Connor, R.J. (2022). Oral nicotine product awareness and use among people who smoke and vape in the US. American Journal of Preventive Medicine, 63(4), 611-618. doi: 10.1016/j.amepre.2022.04.019.

Abstract

Introduction: Tobacco-free oral nicotine products are an emerging class of noncombustible nicotine products. Oral nicotine product sales have increased since 2016, although little research has investigated consumer awareness, use, or correlates of oral nicotine product use. The purpose of this analysis was to assess the prevalence and correlates of oral nicotine product awareness and use.

Methods: This paper is a cross-sectional analysis of 2,507 U.S. participants from Wave 3 (February–June 2020) of the International Tobacco Control Four Country Smoking and Vaping Survey, a population-based survey of current and former cigarette smokers and nicotine vaping product users in the U.S. Oral nicotine product awareness and use prevalence were compared with those of heated tobacco products. Analyses conducted in late 2021 assessed the correlates of oral nicotine product awareness and use such as demographic characteristics, tobacco use (cigarettes, nicotine vaping products, smokeless tobacco), and tobacco quit attempts.

Results: Almost 1 in 5 respondents claimed to have heard of oral nicotine products, 3.0% reported ever use, and 0.9% were current users, all of which were lower than for heated tobacco products. Ever use of oral nicotine products was more common among younger adults (e.g., aged 18–24 years), males, and current users of smokeless tobacco. Oral nicotine product prevalence was higher among those who reported having made attempts to stop smoking or vaping.

Conclusions: Oral nicotine product use was low among current and former smokers and nicotine vaping product users. Oral nicotine product users were demographically similar to use among individuals who smoke/vape and also use smokeless tobacco. Future studies are needed to understand emerging oral nicotine products, particularly whether they are being used as product supplements (dual use), replacements (switching), or cessation aids (quitting).

Citation

Usidame, O., Meng, G., Thrasher, J.F., Thompson, M.E., Fong, G.T., Fleischer, N.L. (2022). The differential impact of the 2000 Canadian graphic warning label policy on smoking prevalence by sex and education: A difference-in-difference-in-difference model. Nicotine and Tobacco Research, 24(11), 1732-1740. doi: 10.1093/ntr/ntac122.

Abstract

Introduction: Using a quasi-experimental design, we compared the impact of the 2000 Canadian introduction of graphic warning labels (GWLs) on differences in smoking prevalence by sex and education, to the United States (US), where no GWLs were introduced.

Methods: We pooled 1999-2004 data from the Canadian Tobacco Use Monitoring Survey (CTUMS) and the US Behavioral Risk Factor Surveillance System (BRFSS). We used a difference-in-difference (DD) model to assess the impact of Canadian policy introduction on smoking prevalence, and a difference-indifference-in-difference (DDD) model to examine differences in the policy impact by sex and education, comparing Canada (the treatment group) with the US (the control group).

Results: From 1999 to 2004, smoking prevalence decreased from 23.7% to 18.6% in Canada, and from 21.7% to 20.0% in the US. Results from the DD regression models showed that Canadian respondents reported lower odds of being a current smoker compared to the US respondents following the 2000 introduction of GWLs (OR= 0.84, 95 % CI 0.74-0.94). The DDD model showed that the impact of the Canadian GWLs vs. the US did not differ by sex or education.

Conclusions: The 2000 Canadian GWL policy reduced smoking prevalence overall, with similar reductions for males and females and across education levels. The impact of the Canadian GWLs in reducing smoking prevalence did not reduce differences by sex or education. Although beneficial for all smokers, GWLs may not serve to decrease existing disparities, especially those by socioeconomic status.

Implications: Existing evidence shows that GWL implementation is associated with reductions in smoking prevalence. But there is limited evidence from past evaluation studies on whether the impact of GWLs on smoking prevalence differs by sociodemographic subgroup. Our findings confirm existing studies that the 2000 implementation of GWLs in Canada was significantly associated with an overall reduction in smoking prevalence in Canada compared to the US. However, our study improves existing evidence by showing that the impact of the Canadian GWLs on smoking prevalence did not differ by sex or education, and thus did not reduce existing smoking disparities by educational levels.

Citation

Gorniak, B., Yong, H.H., Borland, R., Cummings, K.M., Thrasher, J.F., McNeill, A., Hyland, A., Fong, G.T. (2021). Do post-quitting experiences predict smoking relapse among former smokers in Australia and the United Kingdom? Findings from the International Tobacco Control Surveys. Drug and Alcohol Review, 41(4), 883-889.

Abstract

Introduction: Many smokers attempt to stop smoking every year, but the vast majority of quit attempts fail. This study examined prospectively the association between post-quitting experiences and smoking relapse among ex-smokers in Australia and the United Kingdom.

Methods: Data came from 584 adult ex-smokers from Australia and the United Kingdom who participated in Wave 9 of the International Tobacco Control Four Country Survey and successfully followed up a year later (Wave 10). Binary logistic regression was used to examine whether baseline post-quitting experiences predicted relapse back to smoking at follow-up.

Results: Ex-smokers who perceived their stress coping ability had gotten worse since quitting were more likely to relapse back to smoking compared to their counterparts who reported no change (odds ratio = 5.77, 95% confidence interval = 1.64, 20.31, P < 0.01). Ex-smokers who reported their homes had become fresher and cleaner post quitting were less likely to relapse compared to those who did not notice any change (odds ratio = 0.34, 95% confidence interval = 0.13, 0.93, P < 0.05). Perceived changes in life enjoyment, negative affect control, social confidence, work performance, leisure time and financial situation did not independently predict relapse. No country differences were found.

Discussion and conclusions: The study showed that ex-smokers' relapse risk was elevated if they perceived any negative impact of quitting on their stress coping whereas relapse risk was reduced if they perceived any positive impact of quitting on the home (e.g. fresher and cleaner). Helping ex-smokers to develop alternative stress coping strategies and highlighting the positive impacts of quitting smoking on the homes may help protect against smoking relapse.