Development of a measure of the latency to needing a cigarette

Smoking Cessation in Adolescents: targeted approaches that work

Smoking Cessation in adolescents can be considered in a developmental context to enable the clinician to individualise the appropriate assessment and management of the young person they are seeing whether it is in a primary or tertiary care setting. Adolescence is a time of rapid neurocognitive and hormonal change with these factors affected by personality and behavioural factors as well as family, cultural and psychosocial context. Adolescents are uniquely vulnerable to smoking initiation and nicotine addiction throughout these years. Increased awareness of the risks of smoking and using opportunities to assess and intervene regarding smoking cessation are integral to clinical practice for all clinicians seeing young people. This review will discuss the demographics of adolescent smoking, risk factors, assessing smoking and nicotine addiction, the importance of brief interventions, the evidence base for appropriate interventions, particularly in high risk groups and will emphasise innovative training for health professionals in adolescent smoking cessation.

Can tobacco dependence provide insights into other drug addictions?

Within the field of addiction research, individuals tend to operate within silos of knowledge focused on specific drug classes. The discovery that tobacco dependence develops in a progression of stages and that the latency to the onset of withdrawal symptoms after the last use of tobacco changes over time have provided insights into how tobacco dependence develops that might be applied to the study of other drugs.As physical dependence on tobacco develops, it progresses through previously unrecognized clinical stages of wanting, craving and needing. The latency to withdrawal is a measure of the asymptomatic phase of withdrawal, extending from the last use of tobacco to the emergence of withdrawal symptoms. Symptomatic withdrawal is characterized by a wanting phase, a craving phase, and a needing phase. The intensity of the desire to smoke that is triggered by withdrawal correlates with brain activity in addiction circuits. With repeated tobacco use, the latency to withdrawal shrinks from as long as several weeks to as short as several minutes. The shortening of the asymptomatic phase of withdrawal drives an escalation of smoking, first in terms of the number of smoking days/month until daily smoking commences, then in terms of cigarettes smoked/day.The discoveries of the stages of physical dependence and the latency to withdrawal raises the question, does physical dependence develop in stages with other drugs? Is the latency to withdrawal for other substances measured in weeks at the onset of dependence? Does it shorten over time? The research methods that uncovered how tobacco dependence emerges might be fruitfully applied to the investigation of other addictions.

Levels of physical dependence on tobacco among adolescent smokers in Cyprus

PURPOSE

The purpose of this study is to assess tobacco dependence among Cypriot adolescents and examine its association to cigarette consumption and attitudes towards smoking.

METHODS

The current study used cross-sectional data from the 2011 Cyprus Global Youth Tobacco Survey which adopted multistage cluster sampling methods to select adolescents registered in middle and high schools in Cyprus. Tobacco use, physical dependence on tobacco, and attitudes towards tobacco use were measured in 187 adolescents aged 13-18years old who reported that they had smoked at least once in the preceding 30days. Physical dependence was assessed using the Levels of Physical Dependence scale.

RESULTS

Physical dependence was present in 86% of the adolescent smokers. The mean latency to needing among smokers in the highest dependence group was 101h. Significant associations were observed between physical dependence and the perceived difficulty in quitting (OR=13.1, 95% CI: 4.0, 43.0) as well as the expectation to continue smoking for the next five years (OR=3.3, 95% CI: 1.3, 8.4). Significant associations were also observed between physical dependence and the number of smoking days per month, daily smoking, daily cigarette consumption, lifetime cigarette consumption, and perceived difficulty in abstaining from smoking for one week.

CONCLUSIONS

Physical dependence provides a symptom-based approach to assess dependence and it is a strong predictor of adolescents' perceptions of their ability to quit or to refrain from smoking for a week. Physical dependence on tobacco was highly prevalent among adolescent smokers in Cyprus and it was associated with greater perceived difficulty in quitting. Interventions targeting adolescent smoking must account for the high prevalence of physical dependence.

Craving, cue reactivity, and stimulus control among early-stage young smokers: effects of smoking intensity and gender

INTRODUCTION

Smoking initiation usually begins in adolescence, but how and for whom nicotine dependence emerges during this period is unclear. The cue-reactivity paradigm is well suited to examine one marker of dependence: craving-related stimulus control, i.e., the ability of environmental cues to elicit craving to smoke. This study examined the effects of both level of smoking involvement (daily vs. occasional smoking) and gender on reactivity to both smoking and alcohol cues.

METHODS

Young (age range 16-20; 42% female) daily (n = 55) and occasional (n = 52) smokers were exposed to each of three counterbalanced cues: (a) in vivo smoking (e.g., sight, smell, lighting of cigarette), (b) alcohol (e.g., opening, pouring, and smell of preferred beverage), and (c) neutral cue.

RESULTS

Daily smokers exhibited higher levels of tonic (i.e., noncue-elicited) craving than did occasional smokers. Both groups showed significant increases in craving in response to cues (i.e., cue-elicited craving), with little evidence that cue-elicited craving differed between groups. Females were more cue reactive to both the alcohol and smoking cues than males, particularly for the positively reinforced aspects of smoking (i.e., hedonic craving). There were no gender × group interaction effects in response to either the alcohol or the smoking cue.

CONCLUSIONS

Findings show the presence of cue-elicited craving even among occasional smokers and are consistent with literature demonstrating heightened sensitivity to environmental cues among females. Cue-elicited craving may be one mechanism that contributes to the maintenance of smoking behavior and perhaps to the development of nicotine dependence within early stage smokers.

Perceptions of addiction, attempts to quit, and successful quitting in nondaily and daily smokers

We aimed to qualitatively examine differences in perceptions of addiction, attempts to quit, and successful quitting among nondaily versus daily college student smokers. We conducted 16 focus groups with a total of 73 college student smokers from the southeastern U.S. Focus groups were homogenous in terms of gender, smoking status (nondaily, daily), and type of school (2-year college, 4-year university). Questions centered on perceptions of addiction, their own addiction, what constitutes a quit attempt, and successful quitting. Themes that emerged among all smokers regarding conceptualization of general addiction included physiological and psychological dependence and an inability to quit smoking. In terms of their own addiction, nondaily smokers referenced their ability to quit and sense of choice to smoke as factors indicating a lack of addiction, whereas daily smokers reported dependence symptoms and their inability to control their smoking indicating addiction. Nondaily smokers discussed quit attempts in terms of making the decision to quit and avoiding situational triggers, whereas daily smokers reported taking more behavioral steps toward cessation (e.g., not buying cigarettes, reducing cigarette consumption). With regard to successful cessation, both groups identified losing the desire to smoke as a hallmark. However, nondaily smokers reported that the decision to quit might constitute successful cessation; daily smokers had more strict behavioral criteria such as abstinence for an extended period of time. The different perceptions of one's own addiction, attempting to quit smoking, and successful quitting suggest the need to improve assessments of these factors, particularly among nondaily smokers.

Electronic cigarettes for smoking cessation: a randomised controlled trial

BACKGROUND

Electronic cigarettes (e-cigarettes) can deliver nicotine and mitigate tobacco withdrawal and are used by many smokers to assist quit attempts. We investigated whether e-cigarettes are more effective than nicotine patches at helping smokers to quit.

METHODS

We did this pragmatic randomised-controlled superiority trial in Auckland, New Zealand, between Sept 6, 2011, and July 5, 2013. Adult (≥18 years) smokers wanting to quit were randomised (with computerised block randomisation, block size nine, stratified by ethnicity [Māori; Pacific; or non-Māori, non-Pacific], sex [men or women], and level of nicotine dependence [>5 or ≤5 Fagerström test for nicotine dependence]) in a 4:4:1 ratio to 16 mg nicotine e-cigarettes, nicotine patches (21 mg patch, one daily), or placebo e-cigarettes (no nicotine), from 1 week before until 12 weeks after quit day, with low intensity behavioural support via voluntary telephone counselling. The primary outcome was biochemically verified continuous abstinence at 6 months (exhaled breath carbon monoxide measurement <10 ppm). Primary analysis was by intention to treat. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12610000866000.

FINDINGS

657 people were randomised (289 to nicotine e-cigarettes, 295 to patches, and 73 to placebo e-cigarettes) and were included in the intention-to-treat analysis. At 6 months, verified abstinence was 7·3% (21 of 289) with nicotine e-cigarettes, 5·8% (17 of 295) with patches, and 4·1% (three of 73) with placebo e-cigarettes (risk difference for nicotine e-cigarette vs patches 1·51 [95% CI -2·49 to 5·51]; for nicotine e-cigarettes vs placebo e-cigarettes 3·16 [95% CI -2·29 to 8·61]). Achievement of abstinence was substantially lower than we anticipated for the power calculation, thus we had insufficient statistical power to conclude superiority of nicotine e-cigarettes to patches or to placebo e-cigarettes. We identified no significant differences in adverse events, with 137 events in the nicotine e-cigarettes group, 119 events in the patches group, and 36 events in the placebo e-cigarettes group. We noted no evidence of an association between adverse events and study product.

INTERPRETATION

E-cigarettes, with or without nicotine, were modestly effective at helping smokers to quit, with similar achievement of abstinence as with nicotine patches, and few adverse events. Uncertainty exists about the place of e-cigarettes in tobacco control, and more research is urgently needed to clearly establish their overall benefits and harms at both individual and population levels.

FUNDING

Health Research Council of New Zealand.

What aspect of dependence does the fagerström test for nicotine dependence measure?

Although the Fagerström Test for Nicotine Dependence (FTND) and the Heaviness of Smoking Index (HSI) are widely used, there is a uncertainty regarding what is measured by these scales. We examined associations between these instruments and items assessing different aspects of dependence. Adult current smokers (n = 422, mean age 33.3 years, 61.9% female) completed a web-based survey comprised of items related to demographics and smoking behavior plus (1) the FTND and HSI; (2) the Autonomy over Tobacco Scale (AUTOS) with subscales measuring Withdrawal, Psychological Dependence, and Cue-Induced Cravings; (3) 6 questions tapping smokers' wanting, craving, or needing experiences in response to withdrawal and the latency to each experience during abstinence; (4) 3 items concerning how smokers prepare to cope with periods of abstinence. In regression analyses the Withdrawal subscale of the AUTOS was the strongest predictor of FTND and HSI scores, followed by taking precautions not to run out of cigarettes or smoking extra to prepare for abstinence. The FTND and its six items, including the HSI, consistently showed the strongest correlations with withdrawal, suggesting that the behaviors described by the items of the FTND are primarily indicative of a difficulty maintaining abstinence because of withdrawal symptoms.

Neuroadaptation in nicotine addiction: update on the sensitization-homeostasis model

The role of neuronal plasticity in supporting the addictive state has generated much research and some conceptual theories. One such theory, the sensitization-homeostasis (SH) model, postulates that nicotine suppresses craving circuits, and this triggers the development of homeostatic adaptations that autonomously support craving. Based on clinical studies, the SH model predicts the existence of three distinct forms of neuroplasticity that are responsible for withdrawal, tolerance and the resolution of withdrawal. Over the past decade, many controversial aspects of the SH model have become well established by the literature, while some details have been disproven. Here we update the model based on new studies showing that nicotine dependence develops through a set sequence of symptoms in all smokers, and that the latency to withdrawal, the time it takes for withdrawal symptoms to appear during abstinence, is initially very long but shortens by several orders of magnitude over time. We conclude by outlining directions for future research based on the updated model, and commenting on how new experimental studies can gain from the framework put forth in the SH model.

Development and psychometric properties of the health-risk behavior inventory for Chinese adolescents

BACKGROUND

There is a growing body of research investigating adolescent risk behaviors in China, however, a comprehensive measure that evaluates the full spectrum of relevant risk behaviors is lacking. In order to address this important gap, the current study sought to develop and validate a comprehensive tool: the Health-Risk Behavior Inventory for Chinese Adolescents (HBICA).

METHODS

Adolescents, ages 14-19  years (n = 6,633), were recruited from high schools across 10 cities in mainland China. In addition, a clinical sample, which included 326 adolescents meeting DSM-IV criteria for Conduct Disorder, was used to evaluate predictive validity of the HBICA. Psychometric properties including internal consistency (Cronbach's alpha), test-retest reliability, convergent validity, and predictive validity were analyzed.

RESULTS

Based upon item analysis and exploratory factor analysis, we retained 33 items, and 5 factors explained 51.75% of the total variance: Suicide and Self-Injurious Behaviors (SS), Aggression and Violence (AV), Rule Breaking (RB), Substance Use (SU), and Unprotected Sex (US). Cronbach's alphas were good, from 0.77 (RB) to 0.86 (US) for boys, and from 0.74 (SD) to 0.83(SS) for girls. The 8  weeks test-retest reliabilities were moderate, ranged from 0.66 (AV) to 0.76 (SD). External validities was strong, with Barratt Impulsiveness Scale-11 was 0.35 (p < 0.01), and with aggressive behavior and rule-breaking behavior subscales of the Youth Self Report were 0.54 (p < 0.01) and 0.68 (p < 0.01), respectively. Predictive validity analysis also provided enough discriminantity, which can distinguish high risky individual effectively (cohen' d = 0.79-2.96).

CONCLUSIONS

These results provide initial support for the reliability and validity of the Health-Risk Behavior Inventory for Chinese Adolescents (HBICA) as a comprehensive and developmentally appropriate assessment instrument for risk behaviors in Chinese adolescents.

A comparison of the autonomy over tobacco scale and the Fagerström test for nicotine dependence

The autonomy over tobacco scale (AUTOS) is a 12-item theory-based instrument used to measure tobacco dependence in smokers. It provides separate measures of three factors that make smoking cessation more difficult: withdrawal symptoms, psychological dependence, and cue-induced urges to use tobacco. We compared the internal reliability and concurrent validity of the AUTOS to those of the Fagerström test for nicotine dependence (FTND). Adult current smokers (n=422; 62% female; 86.8% white; mean age 33.3 years, SD=13.7; 57% daily smokers) completed an anonymous web-based survey that included the AUTOS, the FTND and 11 smoking-related behavioral measures. Cronbach's α was .94 for the AUTOS and α>.75 for each of the 3 subscales; α=.73 for the FTND. The AUTOS and its subscales correlated with all measures of concurrent validity (r=.70 between AUTOS & FTND). The AUTOS correlated better than the FTND with the Hooked on Nicotine Checklist, the longest period of abstinence, latency to wanting, percentage of time a person smokes because of momentary need, pleasure from smoking, days smoked per month, and concern about deprivation. The measures showed similar correlations with the latencies to craving and needing. The FTND correlated better with the duration of smoking and cigarettes smoked per day. Based on these results and those from prior studies, we conclude that the AUTOS offers researchers a valid and highly reliable, theory-based measure that is more versatile in its applications than the FTND.

Does progression through the stages of physical addiction indicate increasing overall addiction to tobacco?

RATIONALE

With physical addiction to tobacco, abstinence triggers a desire to smoke. As physical addiction advances, the desire to smoke changes in quality and intensity from wanting, to craving, to needing. A prior study in adolescents suggested that this progression signifies increasing addiction.

OBJECTIVE

We sought to determine if the sequential appearance of wanting, craving and needing provides an indication of the intensity of other markers of tobacco addiction including psychological and behavioral indicators.

METHODS

A web-based survey was completed by 422 smokers ages 18-78 years. Subjects were assigned to one of four qualitatively distinct stages of physical addiction based on their most advanced symptom: 1-none, 2-wanting, 3-craving, or 4-needing. Using linear Chi square and ANOVA, we determined if higher stages were associated with higher levels of tobacco addiction on more than a dozen measures.

RESULTS

16.8% of subjects were in stage 1, 26.1% in stage 2, 17.1% in stage 3 and 40.0% in stage 4. Each step up in stage was associated with higher levels of addiction as measured by the Fagerström Test for Nicotine Dependence, the Hooked on Nicotine Checklist, the Autonomy over Tobacco Scale, and higher levels of psychological dependence, duration of tobacco use, frequency of tobacco use, daily cigarette consumption, and 10 additional measures.

CONCLUSIONS

In this cross-sectional study, each sequential stage of physical addiction was associated with higher levels of every indicator of addiction. The data suggest that the stages of progression of physical addiction provide a global indication of the severity of tobacco addiction.

An evaluation of a clinical approach to staging tobacco addiction

OBJECTIVES

To determine whether adolescents' symptom reports are consistent with the developmental sequence of tobacco addiction and whether the sequential appearance of these symptoms signifies increasing addiction.

STUDY DESIGN

An anonymous survey was administered to 349 tobacco users in grades 9 through 12 in Florida. The combinations of withdrawal symptoms reported were examined to determine whether they were consistent with the developmental sequence described by case reports (wanting, then craving, then needing). Dependence was measured by several validated measures, including the Hooked on Nicotine Checklist, the Autonomy Over Tobacco Scale, and the modified Fagerström Tolerance Questionnaire.

RESULTS

The combinations of withdrawal symptoms reported by 99.4% of subjects were consistent with case reports stating that wanting, craving, and needing develop in that sequence. Across the stages, from wanting to needing, higher stages were associated with significant increases in the strength of addiction as measured by the Hooked on Nicotine Checklist, the Autonomy Over Tobacco Scale, the modified Fagerström Tolerance Questionnaire, and all other measures.

CONCLUSIONS

Our data confirmed that withdrawal symptoms develop in an orderly sequence, as proposed, and indicate that each progressive step along the sequence of wanting, craving, and needing represents a substantial increase in tobacco addiction. This provides the foundation for a clinical approach to staging the progression of tobacco addiction.

Thwarting science by protecting the received wisdom on tobacco addiction from the scientific method

In their commentary, Dar and Frenk call into question the validity of all published data that describe the onset of nicotine addiction. They argue that the data that describe the early onset of nicotine addiction is so different from the conventional wisdom that it is irrelevant. In this rebuttal, the author argues that the conventional wisdom cannot withstand an application of the scientific method that requires that theories be tested and discarded when they are contradicted by data. The author examines the origins of the threshold theory that has represented the conventional wisdom concerning the onset of nicotine addiction for 4 decades. The major tenets of the threshold theory are presented as hypotheses followed by an examination of the relevant literature. Every tenet of the threshold theory is contradicted by all available relevant data and yet it remains the conventional wisdom. The author provides an evidence-based account of the natural history of nicotine addiction, including its onset and development as revealed by case histories, focus groups, and surveys involving tens of thousands of smokers. These peer-reviewed and replicated studies are the work of independent researchers from around the world using a variety of measures, and they provide a consistent and coherent clinical picture. The author argues that the scientific method demands that the fanciful conventional wisdom be discarded and replaced with the evidence-based description of nicotine addiction that is backed by data. The author charges that in their attempt to defend the conventional wisdom in the face of overwhelming data to the contrary, Dar and Frenk attempt to destroy the credibility of all who have produced these data. Dar and Frenk accuse other researchers of committing methodological errors and showing bias in the analysis of data when in fact Dar and Frenk commit several errors and reveal their bias by using a few outlying data points to misrepresent an entire body of research, and by grossly and consistently mischaracterizing the claims of those whose research they attack.