Lori M. Diemert

Origin and use of the 100 cigarette criterion in tobacco surveys

Truly global standards and definitions will likely never exist for tobacco control surveillance. One difference across definitions of smoking status is whether or not a lifetime consumption of 100 cigarettes is a necessary criterion for ever and current smoking. Frequently asked questions about this measure demonstrate a need for information on its development and appropriateness in different settings. This commentary attempts to assemble information on the origin and adoption of this measure and provide some critical commentary on its usefulness. The question has been traced to Canadian and American mortality cohort studies from the mid-1950s. From there it has spread to inconsistent use in many settings. To our knowledge, it was not originally (or since) empirically defined as a threshold of exposure related to health consequences or future smoking risk when used in youth. Anecdotal evidence over several decades, however, shows the question has pragmatic utility in self-report data collection. It is a useful, if somewhat arbitrary, screener for “never regular” tobacco use among adults, where never smoking needs to be defined in data collection. Use of the criterion may lower prevalence estimates somewhat. Definitions must always be considered when creating time-trends or international comparisons. There are also circumstances where it is inappropriate to exclude individuals who do not meet this criterion from further data collection, or reports. For research in youth, the criterion typically should be used only with more detailed information about experimentation, but it may be a useful additional indicator of established smoking.

Estimating the number of quit attempts it takes to quit smoking successfully in a longitudinal cohort of smokers.

Objectives The number of quit attempts it takes a smoker to quit successfully is a commonly reported figure among smoking cessation programmes, but previous estimates have been based on lifetime recall in cross-sectional samples of successful quitters only. The purpose of this study is to improve the estimate of number of quit attempts prior to quitting successfully. Design We used data from 1277 participants who had made an attempt to quit smoking in the Ontario Tobacco Survey, a longitudinal survey of smokers followed every 6 months for up to 3 years beginning in 2005. We calculated the number of quit attempts prior to quitting successfully under four different sets of assumptions. Our expected best set of assumptions incorporated a life table approach accounting for the declining success rates for subsequent observed quit attempts in the cohort. Results The estimated average number of quit attempts expected before quitting successfully ranged from 6.1 under the assumptions consistent with prior research, 19.6 using a constant rate approach, 29.6 using the method with the expected lowest bias, to 142 using an approach including previous recall history. Conclusions Previous estimates of number of quit attempts required to quit may be underestimating the average number of attempts as these estimates excluded smokers who have greater difficulty quitting and relied on lifetime recall of number of attempts. Understanding that for many smokers it may take 30 or more quit attempts before being successful may assist with clinical expectations.

Young adult smoking cessation: predictors of quit attempts and abstinence.

We examined young adult smoking cessation behaviors, coding cessation behavior as no attempt, quit attempt (< 30 days), or abstinence (≥ 30 days) during follow-up from July 2005 through December 2008, observed in 592 young adult smokers from the Ontario Tobacco Survey. One in 4 young adults made an attempt; 14% obtained 30-day abstinence. Cessation resources, prior attempts, and intention predicted quit attempts, whereas high self-efficacy, using resources, having support, and low addiction predicted abstinence, indicating that young adult smokers require effective and appropriate cessation resources.

Transitions in Smoking Status Over Time in a Population-Based Panel Study of Smokers

Introduction: Few studies have examined the transitions of smokers in the general population through multiple periods of daily, occasional smoking, or abstinence over time. Transitions from daily to occasional smoking are particularly of interest as these may be steps toward cessation. Methods: The Ontario Tobacco Survey panel study followed 4,355 baseline smokers, semiannually for up to 3 years. Probabilities of all possible changes in smoking status more than 6 months were estimated using 13,000 repeated measures observations generated from sets of 3 consecutive interviews (n = 9,932 daily smokers, 1,245 occasion smokers, and 1,823 abstinent for at least 30 days, at Time 1). Results: For initial daily smokers, an estimated 83% remained daily smokers more than 2 follow-ups. The majority of those who had been abstinent for 30 days at 1 interview, were also former smokers at the following interview. In contrast, occasional smoking status was unstable and future smoking status was dependent upon smoking history and subjective dependence. Among daily smokers who became occasional smokers 6 months later, an estimated 20% became a former smoker, at the next interview, but 50% returned to daily smoking. Daily, turned occasional smokers who rebounded back to daily smoking were more likely to describe themselves as addicted at Time 1. Continuing occasional smokers were somewhat less likely to intend to quit, or have tried, despite considering themselves less addicted. Conclusions: Reducing to occasional smoking can be a stepping stone toward cessation but entails a greater risk of return to daily smoking, compared with complete abstinence.

Exposure to smoking on patios and quitting: a population representative longitudinal cohort study

Objectives Smoke-free policies not only reduce harm to non-smokers, they may also reduce harm to smokers by decreasing the number of cigarettes smoked and increasing the likelihood of a successful quit attempt. However, little is known about the impact of exposure to smoking on patios on smoking behaviour. Design and participants Smokers from the Ontario Tobacco Survey, a longitudinal population representative cohort of smokers (2005–2011). There were 3460 current smokers who had completed one to six follow-ups and were asked at each follow-up whether or not they had been exposed to smoking on patios in the month. Main outcome measures Generalised estimating equations and survival analysis were used to examine the association between exposure to patio smoking and smoking behaviour changes (making a quit attempt and time to relapse after a quit attempt), controlling for potential confounders. Results Smokers who were exposed to smoking on patios (adjusted incident rate ratio (aIRR) = 0.89; 95% CI 0.81 to 0.97) or had been to a patio (aIRR = 0.86; 95% CI 0.74 to 0.99) were less likely to have made a quit attempt than smokers who had not visited a patio. Smokers who were exposed to smoking on patios were more likely to relapse (adjusted HR=2.40; 95% CI 1.07 to 5.40)) after making a quit attempt than those who visited a patio but were not exposed to smoking. Conclusions Exposure to smoking on patios of a bar or restaurant is associated with a lower likelihood of success in a quit attempt. Instituting smoke-free patio regulations may help smokers avoid relapse after quitting.

Predictive validity and measurement issues in documenting quit intentions in population surveillance studies

INTRODUCTION Discrete classification of smokers by intention to quit is desirable in many public health and clinical settings. METHODS Two methodological studies examine measurement properties of measures of discrete-time intention to quit smoking used in population-based tobacco surveillance surveys: an ecological comparison of rates of positive intention in relation to the form of measure used and a prospective analysis examining predictive validity of self-reported quit intentions using multiple possible points of dichotomization of an ordinal measure of intention to quit. The prospective analysis used a repeated measures design and follow-up to 1 year for 2,047 smokers in the Ontario Tobacco Survey cohort. RESULTS The estimated percent of smokers intending to quit was significantly higher using the Stages of Change intention measure, relative to another single question measure. Significant dose-response effects were found. The sooner one intended to quit the more likely one was to make an attempt or achieve at least 30 days abstinence in the next 6 months. Intending to quit in a month or later was not associated with cessation during follow-up among respondents without prior attempts. Examination of cutpoints revealed no value, which maximized both positive and negative prediction. Regardless of quit attempt history, greatest predictive validity was found where respondents stated that they had no intention at all. DISCUSSION Measures of intentions quit smoking in specific time periods and expressed as dichotomies have limited psychometric properties but utility in applied research. Our findings suggest a possible measurement effect warranting caution in comparisons across studies.

Association between use of contraband tobacco and smoking cessation outcomes: a population-based cohort study

Background: High tobacco prices, typically achieved through taxation, are an evidence-based strategy to reduce tobacco use. However, the presence of inexpensive contraband tobacco could undermine this effective intervention by providing an accessible alternative to quitting. We assessed whether the use of contraband tobacco negatively affects smoking cessation outcomes. Methods: We evaluated data from 2786 people who smoked, aged 18 years or older, who participated in the population-based longitudinal Ontario Tobacco Survey. We analyzed associations between use of contraband tobacco and smoking cessation outcomes (attempting to quit, 30-d cessation and long-term cessation at 1 yr follow-up). Results: Compared with people who smoked premium or discount cigarettes, people who reported usually smoking contraband cigarettes at baseline were heavier smokers, perceived greater addiction, identified more barriers to quitting and were more likely to have used pharmacotherapy for smoking cessation. People who smoked contraband cigarettes were less likely to report a period of 30-day cessation during the subsequent 6 months (adjusted relative risk [RR] 0.23, 95% confidence interval [CI] 0.09–0.61) and 1 year (adjusted RR 0.30, 95% CI 0.14–0.61), but they did not differ significantly from other people who smoked regarding attempts to quit (at 6 mo, adjusted RR 0.74, 95% CI 0.43–1.20) or long-term cessation (adjusted RR 0.24, 95% CI 0.04–1.34). Interpretation: Smoking contraband cigarettes was negatively associated with short-term smoking cessation. Access to contraband tobacco may therefore undermine public health efforts to reduce the use of tobacco at the population level.

Health professional advice, use of medications and smoking cessation: A population-based prospective cohort study.

INTRODUCTION The mediating role of cessation medications in the association between health professional advice and quitting behaviors is unclear. METHODS Data were from the Ontario Tobacco Survey longitudinal study, collected between July 2005 and June 2011 in Ontario, Canada. The analytic sample included 3437 baseline smokers who were seen by health professionals during follow-up. Logistic regression with generalized estimating equations and mediation analysis techniques were used to examine the impact of advice and medications on quitting outcomes (making a quit attempt, short-term quitting 1-6months and long-term quitting>6months). RESULTS Those who received advice to quit smoking were more likely to use cessation medications than those who did not receive advice (21% vs. 13%, P<0.001). Receiving advice was associated with making a quit attempt (adjusted odds ratio (OR) 1.25, 95% confidence interval (CI) 1.10-1.41) and long-term quitting (adjusted OR 1.49, 95% CI 1.10-2.02), but not with short-term quitting. Use of cessation medications was associated with making a quit attempt (adjusted OR 11.83, 95% CI 9.93-14.08), short-term quitting (adjusted OR 3.69, 95% CI 2.90-4.68), and long-term quitting (adjusted OR 2.73, 95% CI 1.95-3.82). Using prescription medications was associated with a higher likelihood of quitting short-term (adjusted OR 2.43, 95% CI 2.59-3.74) and long-term (adjusted OR 2.27, 95% CI 1.23-4.17) than using NRT. Use of cessation medications was a significant mediator in the pathway from receiving advice to quitting. CONCLUSION Health professionals should advise smokers to quit and encourage them to use cessation medications, especially prescription medications when trying to quit.

Marketing IQOS in a dark market

Introduction Phillip Morris International (PMI) is pushing hard to promote IQOS heat-not-burn cigarettes in Ontario, Canada. Canada regulates IQOS as a tobacco product so that the robust tobacco marketing ban creates challenges to its promotion. Methods We collected data on IQOS promotion in 49 retail outlets, and through interviews with clerks and observations outside an IQOS store. Results The dominant marketing channel is the visible availability of IQOS in a large number of tobacco retail outlets—1029 across Ontario. Several stores display the price of ‘heated tobacco’ on one of three price signs which are permitted despite Ontario’s total display ban. IQOS boutique stores are the locus of aggressive promotion including exchanging a pack of cigarettes or lighter for an IQOS device, launch parties, ‘meet and greet’ lunches and after-hour events. Outside the store, promotion includes a prominent IQOS sign, a sandwich board sign reading ‘Building a Smoke-Free Future’ and sales representatives regularly smoking IQOS. Membership services: Upon acquiring an IQOS device one can register to access the IQOS website store5 and receive customer support services, a map of retail locations and a product catalogue. Members receive regular email invitations to complete surveys with opportunities to win prizes. Conclusions These promotion activities have undoubtedly made substantial numbers of Ontarians aware of IQOS. Yet, the government has not provided guidance as to absolute and relative potential harms. Our observations of tactics to promote a new tobacco product in a dark market may inform government regulatory policy and non-governmental organisation efforts wherever heat-not-burn products are introduced.

Real-World Effectiveness of Pharmaceutical Smoking Cessation Aids: Time-Varying Effects

Background There are a limited number of studies that have examined the real-world effectiveness of smoking cessation aids and relapse longitudinally in population-representative samples. This study examines the association between use of nicotine gum, patch, bupropion, and varenicline and time to relapse as well as any changes in the association with increased length of abstinence. Methods Data of 1821 current adult smokers (18+) making their first serious quit attempt were compiled from 4504 individuals enrolled in the Ontario Tobacco Survey, a representative telephone survey of Ontario adults, which followed smokers every 6 months for up to 3 years. Use of cessation aids at the time of initial report of a quit attempt was analyzed. A flexible parametric survival model was developed to model length of abstinence, controlling for potential confounders. Results The best fit model found knots at 3, 13, 43, and 212 days abstinent, suggesting different rates of relapse in the periods marked by those days. Use of the patch and varenicline was associated with lower rates of relapse, but no positive effect was found for bupropion or nicotine gum. The effectiveness of the patch reversed in effect after the first month of abstinence. Conclusions This study is one of few reports of long-term quitting in a population-representative sample and demonstrates that the effectiveness of some pharmacological cessation aids (the patch and varenicline can be seen in a population sample). Previous failures in real-world studies of the effectiveness of smoking cessation aids may reflect differences in the products individuals use and differences in the timing of self-reported cessation. Implications While a large number of randomized controlled trials have shown the efficacy of many pharmaceutical smoking cessation aids, evidence of their effectiveness in observational studies in the real world is ambiguous. This study uses a longitudinal cohort of a representative sample of smokers to show that the effectiveness of pharmaceutical cessation aids can be demonstrated in real-world use situations, but effectiveness varies by product type and has time-varying effects.