Psychometric properties of measures for electronic cigarette dependence among former-smoking electronic cigarette users.

BACKGROUND: Measures designed to assess electronic cigarette (ECIG) dependence are largely adapted from those developed for cigarette smoking, and have been evaluated mainly among dual ECIG-cigarette users. The present study evaluated the psychometric properties of four dependence measures among former-smoking ECIG users. METHODS: Respondents (N = 187) were daily ECIG users who had formerly smoked cigarettes regularly. As part of an online survey, they completed four dependence measures: Penn State Electronic Cigarette Dependence Index (PSECDI); E-Cigarette Dependence Scale (EDS-4); Glover Nilsson Behavioral Questionnaire (GNBQ); and Diagnostic and Statistical Manual 5th Edition (DSM-5). RESULTS: Confirmatory factor analysis revealed a single factor structure for all four measures, and fit indices were adequate for all models. Most inter-item correlations (mean r's = 0.21 to 0.45) and all item-total correlations (mean r's = 0.53 to 0.80) were significant for all four measures. Internal consistency was highest for the GNBQ (α = 0.86) followed by the EDS-4 (α = 0.81), PSECDI (α = 0.76), and DSM-5 (α = 0.75). Age of ECIG initiation was correlated negatively with scores on the EDS-4 and DSM-5, while number of ECIG quit attempts was correlated positively with scores on all measures except the GNBQ. Convergent validity was highest for comparisons between the EDS-4 and PSECDI (r = 0.75) though all comparisons were significant (p's < 0.001). CONCLUSIONS: All four measures demonstrated acceptable reliability and validity in this sample of former-smoking ECIG users.

Tobacco-Free Oral Nicotine Product Use Among Youth in the U.S., 2019-2021.

Introduction: Novel tobacco-free oral nicotine products are not combusted, easy to conceal, available in flavors, and do not contain tobacco leaf. Since 2016, oral nicotine product sales have increased and may be gaining popularity among youth. This study aims to examine the trends in the prevalence and correlates of oral nicotine product use among U.S. youth. Methods: Data from participants aged 16-19 years in the U.S. International Tobacco Control Policy Evaluation Project Youth Tobacco and Vaping Survey were analyzed cross-sectionally from August 2019, February 2020, August 2020, February 2021, and August 2021. Weighted descriptive statistics and logistic regressions were used to describe the use and correlates of oral nicotine products. Results: Oral nicotine product use significantly increased from 3.5% in August 2019 to 4.1% in August 2021. Oral nicotine product use was most prevalent among those aged 18 years, male, and non-Hispanic White. Those who used cigarettes (AOR=2.18, 95% CI=19.37, 40.88), nicotine vaping products (AOR=4.27, 95% CI=3.02, 6.04), and smokeless tobacco (AOR=28.14, 95% CI=19.37, 40.88) in the past 30 days were more likely to report recent use of oral nicotine products. Conclusions: Although oral nicotine products are less popular among U.S. youth than cigarettes, nicotine vaping products, and smokeless tobacco, their prevalence of use significantly increased. Oral nicotine product users are more likely to use other nicotine products, but the availability of flavors and easy-to-conceal design may be appealing to those who may not use nicotine products. Researchers should continue to observe the behaviors associated with oral nicotine product use to inform the need for future regulatory efforts.

Comparing POD and MOD ENDS Users' Product Characteristics, Use Behaviors, and Nicotine Exposure.

INTRODUCTION: POD electronic nicotine delivery systems (ENDS), often containing high concentrations of nicotine salts, have replaced MODs (ie, open/modifiable devices) as the most popular devices. The purpose of this study was to compare device/liquid characteristics, use behavior, and nicotine exposure between POD and MOD users. METHODS: Data from the initial visit of a prospective observational study of exclusive ENDS users compared MOD (n = 48) and POD (n = 37) users. Participants completed questionnaires on demographic characteristics, patterns of ENDS use, and ENDS features. A urine sample was collected to test for cotinine and an ENDS liquid sample was collected to test for nicotine and salts. Puff topography was captured during an ad libitum bout at the end of the session. RESULTS: MOD and POD users did not differ on demographic characteristics. MOD users reported purchasing more liquid in the past month than POD users (180.4 ±â€…28.0 vs. 50.9 ±â€…9.0 ml, p < .001). Differences in characteristics of devices used by MOD and POD users included flavor type (p = .029), nicotine concentration (liquids used by MOD users contained less nicotine than those used by POD users: 8.9 ±â€…2.0 vs. 41.6 ±â€…3.2 mg/ml, p < .001), and presence of the nicotine salt (fewer MOD liquids had salts present than POD liquids: 11.9% vs. 77.4%, p < .001). User groups did not differ on urinary cotinine levels or puff topography (ps > .05). CONCLUSIONS: Despite different characteristics of MOD and POD ENDS, users of those products are exposed to similar amounts of nicotine, likely due to using more liquid among MOD users. IMPLICATIONS: This study directly compares ENDS product characteristics, user behavior, and nicotine exposure between MOD and POD ENDS users. Although POD products contained higher nicotine concentrations compared to MOD products, users of PODs reported consuming less liquid than MOD users. Ultimately, MOD and POD users were exposed to similar levels of nicotine, suggesting users behaviorally compensate for differences in product characteristics.

Predictors of electronic cigarette dependence among non-smoking electronic cigarette users: User behavior and device characteristics.

INTRODUCTION: ECIGs differ in their ability to deliver nicotine to the user and, consequently, they may differ in their ability to produce dependence. This study examined individual device characteristics, device type, and user behaviors as predictors of ECIG dependence in a sample of never-smoking ECIG users. METHODS: Participants (N = 134) completed an online survey that assessed demographics, ECIG use behavior, and ECIG dependence as measured via the Penn State Electronic Nicotine Dependence Index (PSECDI) and E-cigarette Dependence Scale (EDS-4). Participants uploaded a picture of their personal ECIG device/liquid, which was coded by raters to identify product features. Multivariable linear regressions examined device characteristics (e.g., adjustable power, nicotine concentration) and device type (e.g., vape pen, mod, pod, modern disposable) as predictors of dependence controlling for demographics and user behaviors (e.g., ECIG use duration and frequency, other tobacco use). RESULTS: Longer durations of ECIG use and more use days/week were associated significantly with higher PSECDI (ß's = 0.91 and 1.90, respectively; p's < 0.01) and EDS-4 scores (ß's = 0.16 and 0.28, respectively; p's < 0.01). Higher nicotine concentrations were associated with higher PSECDI scores only (ß = 0.07, p =.011). Dependence scores did not differ as a function of ECIG device types after controlling for covariates. CONCLUSIONS: ECIG dependence was observed among the never-smoking ECIG users in this sample, regardless of their ECIG device/liquid features. Findings suggest that regulatory efforts aimed at reducing the dependence potential of ECIGs in never smokers should focus on overall nicotine emissions rather than product features.

Oral Nicotine Product Awareness and Use Among People Who Smoke and Vape in the U.S.

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).

Evolution of tobacco products: recent history and future directions.

Declines in cigarette smoking prevalence in many countries and the consolidation of the tobacco industry have prompted the introduction of other forms of nicotine delivery. These include electronic nicotine delivery systems (ENDS), heated tobacco products (HTPs) and oral nicotine products (ONPs). Evolving over time, some of these products now deliver nicotine at levels comparable to cigarettes and may serve as effective substitutes for smokers. However, certain products, especially ENDS like JUUL, have also appealed to youth and non-smokers, prompting concerns about expanding nicotine use (and potentially nicotine addiction). The tobacco industry could shift away from primarily promoting cigarettes to promoting ENDS, HTPs and/or ONPs, though at this time it continues to heavily promote cigarettes in low and middle-income countries. Differing regulatory regimes may place upward and downward pressures on both cigarettes and these newer products in terms of population use, and may ultimately drive the extent to which cigarettes are or are not displaced by ENDS, HTPs and/or ONPs in the coming decade.

Device features and user behaviors as predictors of dependence among never-smoking electronic cigarette users: PATH Wave 4.

INTRODUCTION: Electronic cigarettes (ECIGs) vary greatly in their ability to deliver nicotine, which suggests they may also vary in their ability to produce dependence. This study examined individual and combined ECIG device features, and also user behaviors, as predictors of dependence in never-smoking ECIG users. Methods Data were collected from 711 current ECIG users who had smoked <100 cigarettes in their lifetime at Wave 4 of the Population Assessment of Tobacco and Health (PATH) Study. Multivariable linear regressions examined individual (e.g., contains nicotine, uses a tank, flavor preference) and combined (e.g., refillable tanks, refillable mods) device features, and user behaviors (e.g., uses/day) as predictors of dependence, withdrawal, and craving after accounting for demographic variables. Results Results for ECIG dependence and craving showed a similar pattern; higher levels were observed for older age, more frequent past 30-day use, using an ECIG containing nicotine (vs no nicotine), and using a non-refillable cartridge or refillable tank style (vs disposables). Higher withdrawal levels were observed for higher education levels and individual device features of tank (vs no tank), cartridge (vs no cartridge), refillable (vs non-refillable), and "other" flavor preference (vs tobacco flavor). Lower withdrawal levels were associated with a preference for sweet/fruit flavor(s) (vs tobacco flavor). Conclusions Few use behaviors and device features, whether examined alone or in combination, predicted dependence-related outcomes. Findings underscore the challenge with regulating ECIG products in the current marketplace, which is inundated with a myriad of device types.

Timing of smoking cessation treatment integrated into outpatient treatment with medications for opioid use disorder: Feasibility trial.

INTRODUCTION: Cigarette smoking rates among individuals with opioid use disorder (OUD) are notoriously high and may be improved by considering the timing of treatment integration for these two substances. The current study examined the feasibility of a method for assessing the timing of integrating smoking cessation pharmacotherapy within three different phases of outpatient treatment with medication for OUD (MOUD). METHODS: Seventy-four buprenorphine-maintained smokers were enrolled in a quasi-experimental study across three MOUD treatment phases: 0-90 (Phase 1), 91-365 (Phase 2), and > 365 days of MOUD treatment (Phase 3). During a 12-week varenicline-based intervention, the study assessed outcomes daily via text messages (cigarette smoking, varenicline adherence, side effects) or monthly at in-person visits (quit motivation and carbon monoxide levels). RESULTS: Thirty-five participants completed the study, with a lower retention rate in Phase 1 (37.5%) relative to Phases 2 (53.5%) or 3 (57.1%). A trend occurred for Phase 1 participants to report aversive side effects (e.g., abnormal dreams, gastrointestinal distress) on more study days. Among completers, adherence to text messaging and varenicline use was high and independent of MOUD treatment phase. Participants in all phases reported declines in cigarette smoking and increases in quit motivation over time; the study observed biochemically verified tobacco abstinence among only a few participants from Phases 2 or 3. CONCLUSIONS: This feasibility study demonstrates a method to evaluate the timing of treatment integration for cigarette smoking and MOUD. Method strengths include a study schedule that coincided with the MOUD clinic schedule and use of text messaging to encourage varenicline adherence and evaluate outcomes regularly.

Electronic Cigarette Terminology: Where Does One Generation End and the Next Begin?

IMPLICATIONS: The electronic cigarette (ECIG) research community faces several challenges when it comes to regulatory science; not only is the ECIG market changing at a rapid pace, but the terms used by researchers, health organizations, ECIG users, and ECIG manufacturers/distributors to describe devices are inconsistent. These discrepancies make it difficult to advance science and develop regulations. Although researchers have used "generations" to categorize ECIG device types based on various characteristics, with the constantly evolving ECIG market, it is unclear where one "generation" of devices ends and the next begins.

Characteristics and changes over time of nicotine vaping products used by vapers in the 2016 and 2018 ITC Four Country Smoking and Vaping Surveys.

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 4734 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=1058) 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.

Measurement of cigarette smoking: Comparisons of global self-report, returned cigarette filters, and ecological momentary assessment.

Prior work suggests that prospective measurement of cigarette use may be more reliable and valid than retrospective self-reports. Despite several studies comparing retrospective and prospective methods, there are a myriad of prospective methods that have not been directly compared, including spent cigarette filters that are returned to the laboratory by participants and diary logs of cigarette use on an electronic device via ecological momentary assessment. The current secondary data analysis compared the reliability of retrospective global self-report, returned cigarette filters, and electronic diary logs among a sample of cigarette smokers that also use smokeless tobacco (SLT; N = 51) over two consecutive weeks. CPD values also were compared to salivary cotinine levels to determine whether any method was associated more strongly with nicotine/tobacco exposure. Results indicated that CPD values via global self-report were significantly larger than returned filter and diary log daily averages across both weeks (t(50) = 8.28 to 9.35; p < .001). Both prospective measures showed less digit bias and more variation in smoking behavior across days than global self-reports. Only returned CPD values were correlated significantly with salivary cotinine levels (r(593) = 0.09, p = .024). Importantly, most reliability outcomes for returned filters and logged CPD did not differ significantly, suggesting that they may be comparable prospective methods for measuring cigarette use. Because returned filters and diary logs did not differ from one another, researchers' selection of a prospective measurement method should rely on considerations of participant compliance, protocol burden, and specific research questions. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Preliminary Evaluation of Short-Term Abstinence Effects Among Never-Smoking Experienced Users of Modern Electronic Cigarettes.

INTRODUCTION: ECIG use has increased among non-smokers, with the potential negative consequence of developing nicotine dependence. ECIG users report withdrawal symptoms upon abstinence, though the significance of these symptoms has been questioned. This preliminary study aimed to characterize the early timecourse of ECIG withdrawal under forced abstinence. METHODS: Fifteen never-smoking ECIG users completed two conditions whereby participants either abstained from ECIG use (abstinence) or used their own ECIG (ad lib) for 3 h. Puff topography in this latter condition was measured via video observation. Outcome measures included heart rate, subjective ratings of withdrawal, cognitive performance, and choice behavior. RESULTS: Heart rate was lower during abstinence compared to ad lib use (F = 12.60, p < .01, ƞp2 = 0.47). Higher levels of craving (F = 4.98, p < .05, ƞp2 = 0.26) and lower levels of nicotine effects (e.g., dizzy, F = 4.62, p < .05, ƞp2 = 0.36) were reported during abstinence compared to ad lib use. Interaction effects were observed for both factors of the Questionnaire of Smoking Urges: Brief (Fs > 3.56, ps < .05, ƞp2s = 0.21-0.27), with factor scores increasing from baseline to 90 min in the abstinent condition only. Inhibitory control was impaired at 120 min in the abstinent condition only (F = 7.51, p < .05, ƞp2 = 0.50). CONCLUSIONS: Never-smoking ECIG users experienced aversive withdrawal symptoms within 2-3 h of abstinence. Future work should include other control conditions, such as placebo ECIGs or nicotine replacement therapy, and biomarkers of nicotine exposure, as well as examine withdrawal as a function of device type. IMPLICATIONS: Never-smoking ECIG users experience some aversive nicotine withdrawal symptoms within two to three hours of abstinence. Relative to ad lib ECIG use, abstinence decreased heart rate and inhibitory control, as well as increased subjective ratings of withdrawal such as craving and intention to vape. Those same symptoms might be suppressed by self-administration of ECIGs. Experiencing withdrawal upon abstinence may indicate that ECIGs can cause dependence without a history of other tobacco use.

Validation of the Electronic Cigarette Expectancy Scale for Adolescents.

INTRODUCTION: Expectancies of costs and benefits can be predictive of tobacco use, as well as cessation attempts and success. Measuring electronic cigarette (ECIG) expectancies is in its infancy, particularly among adolescents. However, the popularity of adolescent ECIG use demonstrates the need to understand better these contributing factors. Our aim was to evaluate the factor structure and initial psychometric properties of an ECIG expectancies questionnaire adapted from an existing validated scale for conventional cigarette smoking (Smoking Expectancy Scale for Adolescents; SESA). METHODS: Five-hundred sixty-nine adolescents (14-18 years; 60.1% female; 84.1% White) were recruited from high schools and an adolescent medicine clinic. Participants completed a battery of self-report measures, including the ECIG Expectancies Scale for Adolescents (EESA). Exploratory factor analyses were used to examine the underlying factor structure, and convergent validity was evaluated using variables conceptually related to ECIG expectancies. RESULTS: A three-factor solution was chosen based on statistical evidence and conceptual relevance. All three factors - Costs, Social Benefits, and Affective/Weight Benefits - had strong internal consistencies and demonstrated convergent validity via significant associations with peer ECIG use and Conscientiousness. The Costs and Affective/Weight Benefits factors also demonstrated convergent validity with sensation-seeking, intention to use ECIGs, and ECIG use status (current, lifetime, nonuser). CONCLUSION: Results support the initial reliability and validity of the EESA scores. This factor structure is related to, yet different from, that observed not only for the SESA but also for other ECIG-expectancy measures among adult populations.

"Don't Know" Responses for Nicotine Vaping Product Features among Adult Vapers: Findings from the 2018 and 2020 ITC Four Country Smoking and Vaping Surveys.

Nicotine vaping products (NVPs) have evolved rapidly, and some vapers have difficulty reporting about their NVP. NVP knowledge may be important for providing accurate survey data, understanding the potential risks of NVP use, and assessing legal and regulated products. This paper examines current vapers who responded "don't know" (DK) regarding their NVP features. Data are from adult daily/weekly vapers in Waves Two (2018, n = 4192) and Three (2020, n = 3894) of the ITC Four Country Smoking and Vaping Survey. Analyses assessed DK responses for NVP features (e.g., type/appearance, nicotine) and consumption. A DK index score was computed based on the percent of all features with DK responses, which was tested for associations with demographics, smoking/vaping status, NVP features, purchase location, and knowledge of NVP relative risks. NVP description and appearance were easily identified, but DK was more common for features such as nicotine content (7.3-9.2%) and tank/cartridge volume capacity (26.6-30.0%). DK responses often differed by vaping/smoking status, NVP type/appearance, purchase location, and country. Vapers who are younger, use box-shaped NVPs, purchase online, and exclusive daily vapers were associated with lower DK index scores. Higher DK index scores were associated with poorer knowledge of relative health risks of NVP use. The diversity of the NVP market and wide variation in how products are used makes it challenging to capture information from users about device features, such as nicotine content and capacity, in population surveys.

Smokers' perceptions of different classes of cigarette brand descriptors.

INTRODUCTION: Cigarette brand descriptors such as 'light' are banned in several countries and often replaced by alternative descriptors that continue to mislead smokers about the relative risk from those brands. The objective of this study was to evaluate perceptions from current brand descriptors when presented independently of cigarette packaging. METHODS: Eighty-eight daily cigarette smokers attended semi-structured interviews at three US research laboratories in 2018-2019 to assess smokers' perceptions of cigarette brand descriptors in four classes of brand features: prestige, connotation, taste, and color. Participants ranked descriptors within each brand feature on perceived harm, attractiveness, and appeal (willingness to try). Ranked perceptions were described using median rankings and percentages. Chi-squared was used to assess demographic effects on perceptions. Spearman's correlation was used to assess the association between harm, attractiveness, and appeal rankings. RESULTS: Brand descriptors influenced perceptions of harm, attractiveness, and appeal within each brand feature. Smooth was perceived as the most attractive (42.5%) and appealing (33.0%) taste descriptor. Red was perceived as the most harmful (45.4%) and least appealing (22.7%) color descriptor. Perceptions of certain descriptors differed by demographic characteristics such as sex and age. Rankings of attractiveness and appeal were more strongly correlated (r=0.63) than rankings of harm and appeal (r=0.20, p<0.01). CONCLUSIONS: Cigarette manufacturers replaced banned descriptors with alternative descriptors that continue to influence perceptions of cigarettes. Regulatory agencies should closely evaluate all brand descriptors and consider implications for alternative products with fewer regulations.

Cigarette smokers' concurrent use of smokeless tobacco: dual use patterns and nicotine exposure.

BACKGROUND: The concurrent use of cigarettes with other tobacco products, such as smokeless tobacco (SLT), is increasingly common. Extant work with cigarette smokers who also use SLT is based heavily on retrospective reports and between-group comparisons. The purpose of this study was to assess prospectively the patterns of dual users' product use and nicotine exposure on days when cigarettes were smoked exclusively (single use) versus concurrently with SLT (dual use). DESIGN: Forty-six dual cigarette-SLT users recorded their product use in real time via ecological momentary assessment for a 2-week longitudinal design. They responded to questions about situational factors (eg, location, mood) using this same diary, and collected saliva samples each night for later cotinine measurement. At the end of this 2-week period, users reported on their reasons for and beliefs about SLT use. RESULTS: Cotinine levels were significantly higher on dual versus single use days (mean±SEM=374.48±41.08 ng/mL vs 300.17±28.13 ng/mL, respectively; p<0.01), and the number of cigarettes logged was higher on dual versus single use days (11.13±0.98 vs 9.13±1.11, respectively; p<0.01). Product use was distinguished by situational factors, with the strongest predictor being location of use. Moreover, the most common reason for initiating (56.52%) and continuing (67.39%) SLT use was to circumvent indoor smoking restrictions. CONCLUSIONS: Results support the idea of product supplementation rather than replacement among this convenience sample of dual users. For smokers whose primary motivation for SLT use involves situations where they would otherwise be tobacco free, the potential benefits of clean indoor air laws may be diminished.

Personality and impulsivity as predictors of tobacco use among emerging adults: A latent class analysis.

The tobacco industry markets their products toward emerging adults (18-29), with the goal of increasing use among this age group. To inform prevention efforts, researchers are investigating how specific demographic and psychological traits may predict tobacco initiation and continuation. Participants were 578 incoming university freshmen from the Appalachian region. Participants provided information on demographics, personality traits, impulsivity characteristics, lifetime use of cigarettes and electronic cigarettes (ECIGs), and current use of cigarettes, ECIGs, small cigars/cigarillos, large cigars, smokeless tobacco, and waterpipe. Latent class analysis identified tobacco-use classes and regressions identified psychological predictors of class membership. Participants were Nonusers, Experimenters, and Polytobacco Users. Lower agreeableness and conscientiousness as well as higher extraversion and neuroticism were associated with being Experimenters or Polytobacco Users. Lower impulsivity was associated with being Nonusers. Distinct types of emerging adults belong to each tobacco use class, suggesting that individual differences be incorporated in prevention efforts.

Comparison of Measurement Methods for Electronic Cigarette Puff Topography.

OBJECTIVES: Measurement of electronic cigarette (ECIG) puff topography provides an understanding of how product characteristics and user behavior affect nicotine delivery. However, mouthpiece-based topography devices may affect natural puffing behavior. This study was designed to compare ECIG topography measured by mouthpiece-based eTop computerized device and mouthpiece-free video recordings. METHODS: ECiG-naïve cigarette smokers (N = 18) and ECIG-experienced users (N = 25) puffed on a standardized ECIG via eTop or conventionally; both sessions were videotaped. Following overnight abstinence, participants experienced one directed (10 puffs, 30 sec IPI) and 2 ad libitum puffing bouts. Heart rate and subjective response were measured throughout sessions. RESULTS: No statistically significant differences between methods were observed for topography, heart rate, or abstinence-related subjective effects, and both methods were accurate and reliable. Use of a mouthpiece was perceived to alter aspects of ECIG puffing (eg, "reduce enjoyment). CONCLUSIONS: The mouthpiece-based eTop measures ECIG topography precisely as when no mouthpiece is used, and interferes minimally with subjective ECIG experience. Reliable and valid ECIG topography measurement methods are an important regulatory tool, as they can be used to understand the interplay between product design and user behavior to predict toxicant exposure.

What factors reliably predict electronic cigarette nicotine delivery?

BACKGROUND: The ability of an electronic cigarette (e-cigarette) to deliver nicotine effectively may be dependent on features of the device, the liquid and the user. Some of these features have been examined in previous work (eg, liquid nicotine concentration and puff topography), while others have not (eg, nicotine dependence and demographic characteristics). The purpose of this secondary analysis is to examine such features as predictors of e-cigarette nicotine delivery using a relatively large sample. METHODS: Four studies were combined in which e-cigarette-experienced users (n=63; 89% men; 75% white) and e-cigarette-naïve cigarette smokers (n=67; 66% men; 54% white) took 10 puffs from an eGo-style e-cigarette (~7.3 watts) filled with liquid that had a nicotine concentration of 18, 25 or 36 mg/mL. Thus, held constant across all studies were device features of battery/cartomiser style and power level and the topography parameters of puff number and interpuff interval. Blood was sampled before and after use, and puff topography was measured. Three general linear models were conducted to predict plasma nicotine concentrations (pre-post increase) for: (1) e-cigarette users only, (2) smokers only and (3) both groups combined. Predictor variables included puff duration, puff volume, liquid nicotine concentration, presession plasma nicotine concentration, nicotine dependence score (smokers only), gender and race. RESULTS: In all models tested, longer puff durations and higher liquid nicotine concentrations were associated significantly with increased nicotine delivery (ps<0.05). For e-cigarette users only, higher presession nicotine concentration was associated significantly with increased nicotine delivery (p<0.05). CONCLUSIONS: Puff duration and liquid nicotine concentration may be among the more important factors to consider as regulators attempt to balance e-cigarette safety with efficacy. These findings should be interpreted in the context of devices with relatively low power output, a variable not studied here but likely also directly relevant to product regulation.

Piloting a clinical laboratory method to evaluate the influence of potential modified risk tobacco products on smokers' quit-related motivation, choice, and behavior.

Research methods are needed that can predict whether the availability of potential modified risk tobacco products (MRTPs) may influence smokers' quit-related motivation, choice, and behavior. This pilot study assessed the primary outcomes of feasibility and adherence to address this need using an electronic cigarette (ECIG) as a model MRTP. Cigarette smokers were randomly assigned to use only their own brand of cigarettes (OB-only) or a second-generation ECIG (18 ng/ml nicotine) plus their OB cigarettes (ECIG+OB) ad libitum for four weeks. Participants logged products using a mobile device, collected used cigarette filters, and provided saliva samples every day for analysis of cotinine. They returned to the lab once per week to provide a breath sample and accept or decline a choice to quit all tobacco products (i.e., cigarettes and/or ECIGs). They also returned for a one-month follow-up visit. Of those participants randomized (n = 60), 56.7% completed the 4-week intervention and 40.0% completed the follow-up visit. The primary reason for withdrawal was poor adherence with mobile device use. Comparable numbers of participants in each group chose to make a quit attempt, although more OB-only participants chose to quit during the first two weeks and more ECIG+OB participants during the last two weeks. With protocol modifications to reduce participation burden, the current method might ultimately be used by regulators to predict how smokers' quit-related motivation, choice, and behavior are influenced by current and future MRTPs.