A review of tobacco smoking in adolescents: treatment implications

Catecholaminergic and cholinergic neuromodulation in autism spectrum disorder: A comparison to attention-deficit hyperactivity disorder

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by social impairments and restricted, repetitive behaviors. Treatment of ASD is notoriously difficult and might benefit from identification of underlying mechanisms that overlap with those disturbed in other developmental disorders, for which treatment options are more obvious. One example of the latter is attention-deficit hyperactivity disorder (ADHD), given the efficacy of especially stimulants in treatment of ADHD. Deficiencies in catecholaminergic systems [dopamine (DA), norepinephrine (NE)] in ADHD are obvious targets for stimulant treatment. Recent findings suggest that dysfunction in catecholaminergic systems may also be a factor in at least a subgroup of ASD. In this review we scrutinize the evidence for catecholaminergic mechanisms underlying ASD symptoms, and also include in this analysis a third classic ascending arousing system, the acetylcholinergic (ACh) network. We complement this with a comprehensive review of DA-, NE-, and ACh-targeted interventions in ASD, and an exploratory search for potential treatment-response predictors (biomarkers) in ASD, genetically or otherwise. Based on this review and analysis we propose that (1) stimulant treatment may be a viable option for an ASD subcategory, possibly defined by genetic subtyping; (2) cerebellar dysfunction is pronounced for a relatively small ADHD subgroup but much more common in ASD and in both cases may point toward NE- or ACh-directed intervention; (3) deficiency of the cortical salience network is sizable in subgroups of both disorders, and biomarkers such as eye blink rate and pupillometric data may predict the efficacy of targeting this underlying deficiency via DA, NE, or ACh in both ASD and ADHD.

Use of Single, Dual, and Poly Tobacco Products in Korean Adolescents

This study aimed to examine the prevalence of single, dual, and poly use of conventional cigarettes, e-cigarettes, and heated tobacco products among Korean adolescent smokers and identify factors related to dual and poly tobacco product use. Data from 4028 current smokers in the 2019 Korea Youth Behavior Web-based Survey were included. Single users accounted for 53.1%, followed by dual users at 24.8% and poly users at 22.1%. The factors influencing dual and poly tobacco product use included male, living in a metropolitan area, risky alcohol drinking, sexual experience, number of cigarettes smoked, secondhand smoke exposure, and easy-to-buy tobacco products. The findings suggest restricting the use of new types of tobacco products in the high-risk group are required to prevent dual and poly use. Furthermore, it is necessary to provide support like education for new tobacco products and smoking cessation, programs for secondhand smoke prevention, or rigorous marketing regulations for adolescents.

[Behavior and attitudes towards smoking among student midwives in Libreville]

BACKGROUND

The midwife, in taking on a public health role, is one of the most important resources for the prevention of smoking and in helping smoking cessation among women of childbearing age thanks to their numerous contacts with pregnant women. With this in mind, we conducted a study among student midwives to examine their smoking behavior, their attitudes towards smoking, and their participation in prevention.

METHOD

This was a descriptive cross-sectional study conducted from 15 January to 15 February 2018 using a self-administered questionnaire and included the student midwives of the University of Health Science at Libreville (Gabon).

RESULTS

A total of 188 student midwives completed the questionnaires (70.7% of students of the 1st year, 15.0% of students of the 2nd year and 14.3% of students of the 3rd year). Gaps exist in the knowledge of student midwives regarding the risks of cigarette smoking in pregnancy and its role in the development of complications for the mother and foetus. Overall, 17.1% of student midwives think that smoking is responsible for the occurrence of ectopic pregnancies, 20.3% believe it is responsible for retro-placental haematoma, 17.6% for premature rupture of the membranes. The prevalence of smoking was 11.1% and was most frequent in 2nd year students (25.0%) and 3rd year students (14.8%) (P<0.023). The mean age of beginning smoking was 19.0±4.4 years. The main initiating factors were peer influence (28.6%), pleasure (19.0%) and stress (14.3%). Nicotine dependence was weak to moderate among 48.8% of smokers and absent in 52.2%.

CONCLUSION

Gaps exist in the knowledge of student midwives regarding the risks of cigarette smoking to complications of pregnancy. There is need therefore to include formal training on tobacco control strategies at an early stage in the medical curriculum.

Changes in the Sociodemographic Factors of Tobacco and Alcohol Consumption in Chinese Adolescents from 2004 to 2011

Finding ways to reduce tobacco and alcohol consumption among adolescents has been a major public health challenge in China. In relation to this issue, the current study evaluated the changes in the sociodemographic factors of tobacco and alcohol consumption among Chinese adolescents who are 12–18 years old. Trends in sociodemographic factors associated with tobacco and alcohol consumption were investigated based on the 2004–2011 China Health and Nutrition Survey data. Questionnaires that extracted data on tobacco and alcohol consumption (i.e., prior experience of smoking cigarettes and drinking alcoholic beverages) were distributed. Additional variables (e.g., age, residence, gender, etc.) were used in the analyses. Firth penalized logistic regression was conducted with drinking and smoking status variables as the dependent variables. Male adolescents were more inclined to smoke in 2004, 2006, 2009, and 2011 (p < 0.05 for all). Adolescents aged 15–16 years were more inclined to smoke compared with those aged 12–14 years in 2004, 2006, and 2011 (p < 0.05 for all). Among adolescents aged 15–18 years, older ones were more inclined to not smoke in 2004 (odds ratio (OR) = 0.531, 95% confidence interval (CI) 0.343–0.821). Adolescents who did not attend school were more inclined to smoke in 2004, 2006, 2009, and 2011 (p < 0.05 for all). Adolescents who were drinkers were more inclined to smoke in 2004, 2006, 2009, and 2011 (p < 0.05 for all). Male adolescents were more likely to drink in 2004, 2006, and 2009 (p < 0.05 for all). In 2006 and 2009, adolescents aged 15–16 years were more inclined to drink compared with those aged 12–14 years (p < 0.05 for all). Among adolescents aged 15–18 years, older ones were less inclined to drink in 2004 (OR = 0.719, 95% CI 0.527–0.980) and 2006 (OR = 0.716, 95% CI 0.527–0.972). Adolescents who smoked were more likely to drink in 2004, 2006, 2009, and 2011 (p < 0.05 for all). The prevalence of tobacco and alcohol consumption among adolescents has not changed significantly. The current study identified adolescent high-risk groups for tobacco and alcohol consumption.

Predictors of smoking behaviour among indigenous Sami adolescents and non-indigenous peers in North Norway

Aims: A study was undertaken to examine predictors of smoking behaviour among indigenous Sami adolescents and non-indigenous peers in North Norway, and to examine for ethnic-specific predictors. Methods: This is a cross-sectional and longitudinal school-based and postal questionnaire study initially including 2,718 10th to 12th grade students (response rate (RR): 85%) in 1994—95 (T1). At the three-year follow-up (T2), in 1997 — 98, 1,405 were included (RR: 57%). Indigenous Sami contributed 23% (599/324) of the total samples. Logistic regression was used to examine the influence of sociodemographic and psychosocial predictors on smoking behaviour. Results: The proportions of regular smokers were 33% (729) and 35% (401) at T1 and T2, respectively, while 19% (153) had initiated current smoking during the study period. Substance use, externalizing problems, sexual activity and vocational training (p≤0.01) predicted regular smoking both cross-sectionally and prospectively. Among non-smokers at T1, age and frequent alcohol intoxication predicted current smoking prospectively (p≤0.01). Frequent intoxication predicted all stages of smoking (p≤0.001). Ethnicity did not predict smoking in this study. Laestadian Christian affiliation increased the prevalence of experimental smoking at T1 but only for Sami students. Conclusions: Youth smoking behaviour was strongly associated with risk-taking behaviours, indicating that a broader focus on health-compromising behaviours in anti-smoking campaigns is needed. The findings indicate little need for culturally sensitive anti-smoking campaigns specially designed for indigenous Sami youth, as the main predictors (risk-taking behaviours) were similar across ethnic groups.

[Tobacco consumption and its relationship to the level of regular physical activity and physical fitness in adolescents from the region of Murcia (Spain)]

This study looks at the relationship between tobacco consumption and the physical activity and fitness levels of adolescents. In a sample of 533 adolescents, both a questionnaire to obtain information regarding tobacco consumption and the International Physical Activity Questionnaire for information on physical activity were implemented; a battery of tests to assess physical fitness were also applied. Tobacco consumption was significantly higher in females (32.5%) than in males (25.7%). Levels of physical activity in both males and females were significantly associated with tobacco consumption (p<0.0005). Moreover, subjects who consumed tobacco showed lower overall averages in physical fitness tests than those who did not (4.26 vs. 5.77 in males and 4.54 vs. 6.71 in females). Tobacco consumption is therefore shown to be related to lower levels of physical activity and physical fitness in adolescents.

The Reinforcing Effects of Nicotine in Humans and Nonhuman Primates: A Review of Intravenous Self-Administration Evidence and Future Directions for Research

INTRODUCTION

Cigarette smoking is largely driven by the reinforcing properties of nicotine. Intravenous (IV) self-administration procedures are the gold standard for investigating the reinforcing effects of psychoactive drugs. The goal of this review was to examine the results of published investigations of the reinforcing effects of nicotine measured using IV self-administration procedures in humans and nonhuman primates.

RESULTS

The body of literature using nonhuman primate subjects indicates nicotine functions as a positive reinforcer when available for self-administration via IV catheters. However, it can also be difficult to establish IV nicotine self-administration in nonhuman primates and sometimes supplemental strategies have been required (e.g., priming injections or food deprivation) before subjects acquire the behavior. Although the body of literature using human subjects is limited, the evidence indicates nicotine functions as a reinforcer via the IV route of administration in adult cigarette smokers. Rates of nicotine self-injection can be variable across subjects and responding is sometimes inconsistent across sessions in both humans and nonhuman primates.

CONCLUSIONS

The Family Smoking Prevention and Tobacco Control Act, enacted in 2009, gave the Food and Drug Administration regulatory authority over the manufacture, marketing, and distribution of tobacco products. Research examining the threshold reinforcing doses for initiation and maintenance of nicotine self-administration, comparisons of the reinforcing effects of nicotine in adolescent versus adult subjects, investigations of gender differences in the reinforcing effects of nicotine, and studies of the abuse liability of non-nicotine tobacco product constituents and their ability to alter the reinforcing effects of nicotine will inform potential tobacco regulatory actions.

The Association between Family Structure and Adolescent Smoking among Multicultural Students in Hawaii

Objective

The purpose of this study was to examine whether the prevalence of smoking was associated with family structure among multicultural adolescents and whether there was gender disparity on the association.

Methods

Data were collected from a sample of 7th graders in Hawaii who completed in-class questionnaires in 2004. The final sample included 821 multicultural students from different family structures. Descriptive analyses, Chi-square tests and logistic regression were performed to examine the prevalence of smoking and the association between family structure and smoking prevalence.

Results

This sample contained students who lived in intact (61.7%), single-parent (16.5%), step-parent (15.6%), and no-parent (6.2%) families. The overall prevalence of ever/lifetime smoking was 24.0%, and was not significantly different between genders in each family structure (P > 0.05). Compared with living in intact families, living in single-parent, step-parent, or no-parent families was significantly associated with higher odds of ever/lifetime smoking among all students (P < 0.05) and living in single-parent and step-parent families was significantly associated with higher odds of ever/lifetime smoking among females (P < 0.05) and among males (P < 0.05) respectively, after adjusting for covariates.

Conclusions

These findings suggest that family structure is a risk factor for smoking among multicultural students. Anti-smoking programs should consider this factor.

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We examine if family structure is associated with smoking among Hawaii adolescents.

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Adolescents in non-intact families are more likely to smoke than in intact families.

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Males in step-parent families are more likely to smoke than in intact families.

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Females in single-parent families are more likely to smoke than in intact families.

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Family structure is a risk factor of smoking among multicultural adolescents.

The effectiveness of an integrated multicomponent program for adolescent smoking cessation in Taiwan

If adolescents do not receive appropriate assistance in quitting smoking, they are highly likely to become regular smokers when they enter adulthood. Thus, an effective smoking-cessation program is required. A program was designed based on both the smoking-cessation barriers reported by students and effective strategies derived from the literature. We assigned 143 student smokers from 6 vocational high schools to intervention (n=78) and comparison groups (n=65). Data were collected at the baseline, the end of the program, and 1- and 4-month follow-up time points. For the intervention group, the smoking-abstinence rates confirmed using the urine cotinine test were 22.73% at the end of the program and 20.75% at the 4-month follow-up point. Days smoked in the past month, number of cigarettes smoked per day, and the Fagerström Test for Nicotine Dependence score of the intervention group decreased at all of the time points. The group differences in these variables were statistically significant; the magnitude of effect sizes ranged from 0.44 to 0.95. Multicomponent programs addressing smoking-cessation barriers that students encounter can help adolescents quit smoking.

Fatores associados ao uso regular de cigarros por adolescentes estudantes de escolas públicas de Londrina, Paraná, Brasil

Estudo epidemiológico transversal com objetivo de identificar fatores associados ao uso regular de cigarros por adolescentes. A amostra foi constituída por 517 alunos do 9o ano do Ensino Fundamental de escolas públicas de Londrina, Paraná, Brasil. O instrumento de coleta de dados incluiu características sociodemográficas, relações sociais e comportamentos de risco. Na análise estatística, foi utilizado o modelo de regressão logística com nível de significância em 5%. Relataram uso de cigarros, pelo menos, um dia nos últimos trinta dias 8,9% dos alunos. Os fatores idade ≥ 15 anos (OR = 2,28; IC95%: 1,21-4,32; p = 0,011) e possuir amigos fumantes (OR = 12,62; IC95%: 4,44-35,89; p < 0,0001) associaram-se ao uso regular de cigarros, tanto na análise univariada como na multivariada. Por outro lado, sexo, raça, classe social, morar com pai e mãe, religião, escolaridade materna, experimentação de álcool, atividade física e atividade remunerada não se associaram a essa prática. Esses achados podem subsidiar a elaboração de estratégias antitabágicas direcionadas à comunidade, tendo o adolescente como alvo.

Socioeconomic inequalities in youth smoking in Brazil

OBJECTIVE

The contribution of smoking to socioeconomic inequalities in health is increasing worldwide, including in Brazil. Youth smoking may play an important role in the increasing social inequalities related to smoking. This study investigates social determinants of smoking among 15-year-old to 19-year-old individuals.

DESIGN

Cross-sectional study.

SETTING

The study uses data of 3536 participants aged 15-19 years of age of the Global Adult Tobacco Survey (GATS) and the National Household Sample Survey (Pesquisa Nacional por Amostragem de Domicilio, PNAD) obtained from household interviews. Smoking was defined as currently smoking tobacco products, regardless of frequency. Household socioeconomic indicators included per capita income, the educational level and sex of the head of the household, the presence of smoking restrictions and the number of smokers (excluding adolescents). Adolescent social factors included years of delaying school and social status (full-time student, working, and neither working nor studying). The hierarchical logistic regression analysis considered the effect of the complex sampling design.

RESULTS

From 3536 participants, 6.2% were smokers (95% CI 5.4 to 7.1). More men than women had the habit of smoking (7.2%; 5.9 to 8.6 vs 3.6%; 2.7 to 4.6). The likelihood of smoking was significantly greater for men and older teens. There was an upward trend in the OR of smoking according to the number of smokers in the house. Adolescents living in households with no smoking restrictions had a greater likelihood of being smokers. OR of smoking rose as the number of years of delaying school increased, being about three times greater among adolescents who were working and five times greater among those who were neither studying nor working.

CONCLUSIONS

Results demonstrate that socioeconomic inequality in smoking is established at younger ages and that school delay as well as school abandonment may contribute to increased smoking-related inequalities. Smoking restrictions at home were protective against adolescents becoming smokers. Living with other smokers was a strong predictor of adolescents becoming smokers.

Cigarette smoking as an expression of independence and freedom among inmates in a tobacco-free prison in the United States

INTRODUCTION

Most adults report initiation of cigarette smoking during adolescence, a time also marked by developmental striving for independence and freedom. Tobacco use may retain its association with independence and/or freedom into adulthood. This association may contribute to continued tobacco use and/or increased risk of relapse to smoking among some individuals. This study examines the relationship between cigarette smoking and perceptions of independence and freedom among inmates in a tobacco-free prison in the northeastern United States.

METHODS

Questionnaires administered to 247 male and female inmates 6 weeks prior to scheduled prison release assessed demographics, smoking history, nicotine dependence, attitudes toward smoking, and plans for tobacco use or abstinence after prison release. Perceptions of smoking as an expression of independence and freedom were measured using 2 items. Smoking was assessed 3 weeks postrelease.

RESULTS

Constructs of freedom and independence were correlated but did not overlap completely. Both constructs were negatively associated with plans for smoking abstinence after prison release, and with perceived costs of continued smoking. Number of cigarettes smoked postrelease and perception of the pros of smoking were associated with freedom, but not independence.

CONCLUSIONS

Associations of smoking as an expression of freedom and independence may negatively influence plans for renewed smoking after a forced abstinence. Additional research is needed to determine the degree to which these 2 constructs predict smoking behavior and whether they can be used to improve interventions for incarcerated smokers.

Tobacco use among African-American youth receiving behavioral healthcare services

African-American youth with behavioral health problems may be particularly vulnerable to tobacco use and dependence; however, little is known about overall prevalence and factors associated with tobacco use in this population. The present study compared rates of tobacco use for African-Americans (aged 13-17) receiving behavioral healthcare services to state and national prevalence rates. In addition, we examined whether tobacco use prevalence was related to treatment characteristics and services rendered. Retrospective chart reviews were conducted at an urban, public behavioral healthcare agency for youth admitted in 2009. Tobacco use rates among African-Americans receiving behavioral healthcare services were similar to, and in some cases, higher than statewide and national prevalence rates. While tobacco users were more likely to be enrolled in a substance abuse program than in a mental health program, only 2 of 55 youth reporting tobacco use had received documented tobacco cessation treatment. Future work should focus on implementing tobacco cessation prevention and treatment for these youth.

Gender differences in emotional and behavioral disorders and service use among adolescent smokers: a nationwide Israeli study

Marked gender differences have been identified in cigarette smoking. In this study, we aimed to identify the gender-specific emotional and behavioral disorders among adolescent smokers and their consequent utilization of mental health services. We performed a nationwide survey study of an Israeli representative sample of 906 adolescents and their mothers. Mental disorders were assessed using the Development and Well-Being Assessment (DAWBA) Inventory. Levels of emotional and behavioral difficulties were evaluated using the Strengths and Difficulties Questionnaire (SDQ). Mental health services use and smoking habits were also assessed. Among non-smoker adolescents there were significant gender differences in almost all SDQ scales: emotional problems, pro-social, hyperactivity/inattention and conduct problems, whereas in the smoker group there was a difference only in the SDQ emotional problems scale (both self- and maternal-rated, P<0.001 and P=0.002, respectively). Only marginal difference was noted between males and females in help-seeking for emotional or behavioral problems. Over 50% of both male and female smokers in the study had untreated mental disorders (non-significant gender difference). The well-established gender differences in psychiatric symptomatology narrowed markedly in adolescent smokers; the typical gender difference in disruptive behaviors was lost in the adolescent smoking population. The implications of these findings are particularly relevant to developing more effective gender-specific programs to prevent youth smoking, to facilitate quitting and prepare primary care practitioners to identify mental disorders and behavioral problems in adolescents with a smoking history.

Alcohol, nicotine, caffeine, and mental disorders

Alcohol, nicotine, and caffeine are the most widely consumed psychotropic drugs worldwide. They are largely consumed by normal individuals, but their use is even more frequent in psychiatric patients, Thus, patients with schizophrenia tend to abuse all three substances. The interrelationships between depression and alcohol are complex. These drugs can all create dependence, as understood in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Alcohol abuse is clearly deleterious to the brain, provoking acute and chronic mental disorders, ranging from intoxication with impairment of cognition, to delirium tremens, halluosis, and dementia. In contrast, the main health consequences of nicotine, notably cancer and cardiovascular disases, lie outside the realm of psychiatry However, the mes of nicotine dependence and motivation to smoke or quit are of concern to psychiatrists.

The mediating sex-specific effect of psychological distress on the relationship between adverse childhood experiences and current smoking among adults

Background

Research suggests that ACEs have a long-term impact on the behavioral, emotional, and cognitive development of children. These disruptions can lead to adoption of unhealthy coping behaviors throughout the lifespan. The present study sought to examine psychological distress as a potential mediator of sex-specific associations between adverse childhood experiences (ACEs) and adult smoking.

Method

Data from 7,210 Kaiser-Permanente members in San Diego California collected between April and October 1997 were used.

Results

Among women, psychological distress mediated a significant portion of the association between ACEs and smoking (21% for emotional abuse, 16% for physical abuse, 15% for physical neglect, 10% for parental separation or divorce). Among men, the associations between ACEs and smoking were not significant.

Conclusions

These findings suggest that for women, current smoking cessation strategies may benefit from understanding the potential role of childhood trauma.

Do cognitive attributions for smoking predict subsequent smoking development?

To develop more effective anti-smoking programs, it is important to understand the factors that influence people to smoke. Guided by attribution theory, a longitudinal study was conducted to investigate how individuals' cognitive attributions for smoking were associated with subsequent smoking development and through which pathways. Middle and high school students in seven large cities in China (N=12,382; 48.5% boys and 51.5% girls) completed two annual surveys. Associations between cognitive attributions for smoking and subsequent smoking initiation and progression were tested with multilevel analysis, taking into account plausible moderation effects of gender and baseline smoking status. Mediation effects of susceptibility to smoking were investigated using statistical mediation analysis (MacKinnon, 2008). Six out of eight tested themes of cognitive attributions were associated with subsequent smoking development. Curiosity (β=0.11, p<0.001) and autonomy (β=0.08, p=0.019) were associated with smoking initiation among baseline non-smokers. Coping (β=0.07, p<0.001) and social image (β=0.10, p=<.0001) were associated with smoking progression among baseline lifetime smokers. Social image (β=0.05, p=0.043), engagement (β=0.07, p=0.003), and mental enhancement (β=0.15, p<0.001) were associated with smoking progression among baseline past 30-day smokers. More attributions were associated with smoking development among males than among females. Susceptibility to smoking partially mediated most of the associations, with the proportion of mediated effects ranging from 4.3% to 30.8%. This study identifies the roles that cognitive attributions for smoking play in subsequent smoking development. These attributions could be addressed in smoking prevention programs.

Tobacco use and psychiatric comorbidity among adolescents in substance abuse treatment

Adolescents in substance abuse treatment have approximately four times higher rates of tobacco use compared with adolescents in the general population, yet many substance abuse treatment programs do not provide tobacco cessation interventions. This study examined change in tobacco use among 151 adolescents in state-funded substance abuse treatment from intake to 12-month follow-up in relation to psychiatric comorbidity and substance use. Most adolescents (67.5%) used tobacco at intake and follow-up. Having a diagnosis of a mood, anxiety, or behavioral disorder was significantly associated with change in tobacco use. Individuals with a psychiatric disorder were less likely to be nonusers of tobacco than to be individuals who continued tobacco use (adjusted odds ratio [OR] = 0.153, 95% confidence interval [CI] = 0.040-0.587, p < .01), and they were less likely to have initiated tobacco use at follow-up than individuals who continued tobacco use (adjusted OR = 0.320, 95% CI = 0.105-0.970, p < .05). Contrary to the hypothesis, alcohol use and drug use during the 12-month follow-up was not significantly related to change in tobacco use. Adolescents in substance abuse treatment with comorbid psychiatric disorders may be particularly vulnerable to continuing tobacco use.

A prospective examination of the relationships between PTSD, exposure to assaultive violence, and cigarette smoking among a national sample of adolescents

Research demonstrates robust associations among posttraumatic stress disorder (PTSD), exposure to assaultive violence (i.e., sexual assault, physical assault, and witnessed violence), and cigarette smoking among adults and adolescents. Whether exposure to assaultive violence confers risk for cigarette smoking over and above the effects of PTSD and non-assaultive traumatic events (e.g., motor vehicle accidents) is unclear. The current study prospectively measured PTSD, assaultive violence exposure, non-assaultive traumatic event exposure, and cigarette smoking three times over approximately three years among a nationally representative sample of adolescents (N=3614, age range 12-17 at Wave 1). Results revealed that multiple exposure to assaultive violence at Wave 1 was a consistent and robust prospective predictor of cigarette smoking at Waves 2 and 3. By contrast, PTSD diagnoses and non-assaultive traumatic event exposures at Wave 1 only predicted cigarette smoking at Wave 2, but not at Wave 3. Theoretical and clinical implications are discussed.

Contextual factors associated with smoking among Brazilian adolescents

BACKGROUND

Very few studies have examined the role of school, household and family contexts in youth smoking in middle-income countries.

METHODS

This work describes smoking exposure among 59,992 high school students who took part in the Brazilian Survey of School Health and investigates contextual factors associated with regular smoking, defined as smoking cigarettes at least once in the past 30 days. The explaining variables were grouped into: socio-demographic characteristics, school context, household context and family rapport. Variables independently associated with smoking in each context were identified by multiple logistic regression analysis.

RESULTS

53% of the total sample were girls, 89% were aged 13-15 years. 24% had already experimented with cigarettes, 50% before the age of 12 years. The prevalence of regular smoking was 6.3% (95% CI 5.87 to 6.74), with no sex variation. Smoking was not associated with either the mother's education or the index of household assets. In the multivariable analysis, studying at a private school, the possibility of purchasing cigarettes at school and skipping of classes without parents' consent increased the chances of smoking. In the household context, living with both parents was negatively associated with smoking, while having smoking parents and exposure to other people's smoking was positively related to smoking. In the family context, parental unawareness of what the adolescent was doing increased smoking, but having meals with the mother one or more days per week and parents' negative reactions to adolescent smoking reduced the chances of smoking.

CONCLUSION

The results reinforce the role of school, household and family contexts in youth smoking behaviours and will help improve public health policies aimed at preventing smoking and health promotion in adolescents.

Cognitive attributions for smoking among adolescents in China

To design more effective health communication messages for smoking cessation and prevention, it is important to understand people's own perceptions of the factors that influence their decisions to smoke. Studies have examined cognitive attributions for smoking in Western countries but not in the Chinese cultural context. In a study of 14,434 Chinese adolescents, exploratory factor analysis grouped 17 cognitive attributions into 8 factors: curiosity, coping, social image, social belonging, engagement, autonomy, mental enhancement, and weight control. The factors were ranked based on the participants' self-reports of importance and by the strength of their associations with smoking behavior. Among all smokers, curiosity was the most frequently-ranked attribution factor at the early stages of smoking but not for daily smoking. Coping was highly-ranked across smoking stages. Social image and social belonging were more highly-ranked at earlier stages, whereas engagement and mental enhancement were ranked more highly at later stages of smoking. More attributions were associated with smoking among males than among females. This information could be useful for the development of evidence-based anti-smoking programs in China.

Health risk behaviors in an urban sample of young women who have sex with women

We examined the prevalence of sexual and substance use behaviors among a group of young women who have sex with women (WSW) aged 16 to 24. A convenience sample of 137 young WSW participants completed a confidential survey that included demographics, substance use, and sexual risk behaviors. Descriptive analyses were used to interpret the data. Comparisons were made between rates of risk behaviors in this sample and non-sexual minority youth in a national dataset. The mean age of participants was 19.6 (SD = 2.3) and 59% were from communities of color. Participants reported a history of risky behaviors including anal intercourse with men (26%), monthly binge drinking (22%), pregnancy (20%), and tobacco use (54%). These findings highlight the need for health promotion interventions aimed at reducing risky health behaviors in this highly vulnerable and underserved sub-population of young women.

Contribution of hypothalamic-pituitary-adrenal activity and environmental stress to vulnerability for smoking in adolescents

Although tobacco smoking, which has been linked to depression, is a major public health problem, little is known about the neurobiological factors that confer vulnerability to smoking in youngsters and the effects of adolescent smoking on the course of depression. This study examined whether hypothalamic-pituitary-adrenal (HPA) activity and stressful life experiences are related to smoking behavior in depressed and non-depressed adolescents, and whether smoking predicts a worsening course of depression. Smoking history and stressful experiences were assessed in 151 adolescents (48 with no personal or family history of psychiatric disorder, 48 with no psychiatric history, but at high risk for depression by virtue of parental depression, and 55 with current major depressive disorder). Evening salivary cortisol and nocturnal urinary-free cortisol were measured for three consecutive evenings. The participants were then followed at regular intervals for up to 5 years to assess smoking history, clinical course of depression and stressful experiences during the follow-up period. Increased evening/night-time cortisol levels were associated with both initiation and persistence of smoking during follow-up. Stressful life experiences further increased the risk for smoking in depressed as well as non-depressed youth. Smoking was also associated with a higher frequency of depressive episodes during follow-up. A model that included stressful experiences and cortisol levels reduced the contribution of smoking per se to depression. High evening/night-time cortisol level appears to be a vulnerability marker for smoking in adolescents, with stressful experiences further increasing the risk for smoking in vulnerable youth. High evening/night-time cortisol levels and stressful experiences accounted, at least partially, for the association between depressive illness and smoking behavior.

Educational success and adult health: findings from the Chicago longitudinal study

Growing evidence indicates that education is associated with health, yet we lack knowledge about the specific educational experiences influencing health trajectories. This study examines the role school factors play in the emergence of poor young adult health outcomes for a low-income, minority sample. The following research questions are addressed. First, what are the education-based predictors of daily tobacco smoking, frequent substance use, depression, and no health insurance coverage? Second, do later-occurring school factors explain the association between earlier school measures and the outcomes and, if so, what pathways account for this mediation effect? Data were derived from the Chicago Longitudinal Study, an investigation of a cohort of 1,539 individuals, born around 1980, who attended kindergarten programs in the Chicago Public Schools. Participants were followed prospectively from early childhood through age 24, and study measures were created from various data sources and multiple assessment waves. Findings from probit hierarchical regressions with controls for early sociodemographic covariates indicated that elementary school socioemotional classroom adjustment and high school completion were significantly and negatively associated with all four study outcomes. Participation in the Chicago Child Parent Center preschool program predicted lower rates of both daily tobacco smoking and no health insurance coverage (p < .05). Middle school reading achievement was inversely related to depression (p < .01), while middle school frustration tolerance was inversely associated with daily tobacco smoking and frequent drug use (p < .05). Also, negatively linked to frequent drug use was a high school measure of students' expectation to attend college (p < .01). In nearly all cases, later-occurring school factors fully mediated significant associations between earlier ones and the outcomes. Patterns of mediation were explored along with implications of results.

Tobacco dependence and withdrawal: science base, challenges and opportunities for pharmacotherapy

Several pharmacotherapies for tobacco dependence and withdrawal have been approved by the Food and Drug Administration to aid smoking cessation. These medicines double to triple the odds of cessation compared to placebo, with the diversity in chemical entity (e.g., nicotine, varenicline, bupropion) and route (e.g., nicotine gum and transdermal patch) providing options for people who find a given medication unacceptable or ineffective. Treatments in development include vaccines, combinations of existing products, and new indications, such as reduced tobacco use and exposure. These therapies have been developed on the foundation of research on the neuropharmacology of tobacco dependence and withdrawal. Ongoing research is expected to contribute to more efficacious use of existing therapies and the development of new approaches. This article addresses these developments as well as the challenges to medication development. Challenges include understanding the population-based and individual differences in the vulnerability to dependence and responsiveness to various treatment options, which could contribute to effective treatment to patient matching. Research on the CNS effects of administration and withdrawal of nicotine and other tobacco product constituents is expanding, providing the basis for more effective therapeutic approaches and new medications development. Additionally, whereas medications are approved on the basis of standardized assessments of efficacy and safety in clinical trials, the public health impact of medications depends also on their appeal to smokers and their effectiveness in actual use settings. Research on more effective medication use along with policies that support improved access and utilization are vital to conquering the tobacco epidemic.

A link between adolescent nicotine metabolism and smoking topography

Adult slow nicotine metabolizers have lower smoke exposure, carbon monoxide levels, and plasma nicotine levels than normal and fast metabolizers. Emerging evidence suggests nicotine metabolism influences smoking topography. This study investigated the association of nicotine metabolism (the ratio of plasma 3-hydroxycotinine to cotinine; 3OHCOT/COT) with smoking topography in adolescent smokers (n = 85; 65% female, 68% European American; mean age, 15.3 +/- 1.2 years; mean cigarettes per day, 18.5 +/- 8.5; mean Fagerström Test for Nicotine Dependence, 7.0 +/- 1.2) presenting for a nicotine replacement therapy trial. Measures obtained included puff volume, interpuff interval, number of puffs, puff duration, and puff velocity. Linear regression analysis controlling for hormonal contraception use showed that 3OHCOT/COT ratios predicted mean puff volume in the overall sample (t = 2.126; P = 0.037; adjusted R(2) = 0.067). After gender stratification, faster metabolism predicted higher mean puff volume (t = 2.81; P = 0.009; adjusted R(2) = 0.192) but fewer puffs (t = -3.160; P = 0.004; adjusted R(2) = 0.237) and lower mean puff duration (t = -2.06; P = 0.048; adjusted R(2) = 0.101) among boys only, suggesting that as nicotine metabolism increases, puff volume increases but puffing frequency decreases. No significant relationships were found between nicotine metabolism and total puff volume, mean puff duration, interpuff interval, or puff velocity. If confirmed in a broader sample of adolescent smokers, these findings suggest that as among dependent adult smokers, rate of metabolism among adolescent boys is linked to select parameters of puffing behavior that may affect cessation ability.

Early tobacco smoking in adolescents with externalizing disorders: inferences for reward function

INTRODUCTION

Tobacco smoking is the leading preventable cause of mortality in the United States, and 90% of regular smokers initiate smoking before age 18 years. Factors that confer risk for chronic smoking include psychiatric factors, such as externalizing disorders, and potentially related neurobiological substrates, such as reward function. The present study examined the relationship between the externalizing disorders and the temporal progression of smoking among adolescent smokers.

METHODS

Data were from 64 adolescents who requested smoking cessation treatment and included information on developmental smoking trajectory, number of cigarettes per day, and Fagerström Test for Nicotine Dependence score. This sample was assessed carefully for psychiatric disorders. Analyses examined the relationships between externalizing psychiatric disorders and smoking trajectory.

RESULTS

Adolescents with an externalizing disorder consumed more tobacco in the first 2 years of smoking than those without a disorder. There were no differences in speed of progression between groups, which may index a distinct functional pattern of reward systems that confers vulnerability for tobacco dependence.

DISCUSSION

These data are discussed in terms of potential predictors of early smoking behavior that can inform interventions for adolescents with externalizing behaviors and tobacco dependence. They also provide some hypotheses for how the development of chronic smoking can be influenced by specific patterns of reward responses.

Caffeinated energy drinks--a growing problem

Since the introduction of Red Bull in Austria in 1987 and in the United States in 1997, the energy drink market has grown exponentially. Hundreds of different brands are now marketed, with caffeine content ranging from a modest 50 mg to an alarming 505 mg per can or bottle. Regulation of energy drinks, including content labeling and health warnings differs across countries, with some of the most lax regulatory requirements in the U.S. The absence of regulatory oversight has resulted in aggressive marketing of energy drinks, targeted primarily toward young males, for psychoactive, performance-enhancing and stimulant drug effects. There are increasing reports of caffeine intoxication from energy drinks, and it seems likely that problems with caffeine dependence and withdrawal will also increase. In children and adolescents who are not habitual caffeine users, vulnerability to caffeine intoxication may be markedly increased due to an absence of pharmacological tolerance. Genetic factors may also contribute to an individual's vulnerability to caffeine-related disorders including caffeine intoxication, dependence, and withdrawal. The combined use of caffeine and alcohol is increasing sharply, and studies suggest that such combined use may increase the rate of alcohol-related injury. Several studies suggest that energy drinks may serve as a gateway to other forms of drug dependence. Regulatory implications concerning labeling and advertising, and the clinical implications for children and adolescents are discussed.

Mechanisms of adolescent smoking cessation: roles of readiness to quit, nicotine dependence, and smoking of parents and peers

Multiple levels of influence should be considered in interventions aimed at the adolescent smoker, including psychological, addiction, peer and parental influences. However, the mechanism by which these variables influence the process of smoking cessation in adolescents is not well elucidated. Therefore, this prospective study tested two models among 850 adolescent smokers, specifying the direct and indirect relations between adolescents' readiness to quit smoking, levels of nicotine dependence, and smoking behavior of their parents and friends. One year later smoking cessation was assessed. Results showed that, among adolescent smokers, readiness to quit was positively associated with quit attempts, while nicotine dependence was inversely associated with successful cessation. Instead of a direct relation, parental and peers' smoking were inversely related to smoking cessation through nicotine dependence. The findings emphasize that interventions should be developed and tested within and outside the school setting, as well as within the family situation. In addition, the strong impact of nicotine dependence on successful cessation indicates that a more direct approach is needed to lower nicotine dependence among adolescents.

Time spent with smoking parents and smoking topography in adolescents

Although the relationship between parental and adolescent smoking has been linked to health consequences of smoking, limited study has explored the specific association between exposure to smoking and adolescent smoking topography (the way a cigarette is smoked). As a first step in this line of enquiry, smoking topography measures were collected from 67 adolescent dependent smokers. Participants smoked one cigarette of their own brand while being monitored by a computer-based smoking-topography unit and completed questionnaires about their time spent daily with parents who smoke. Pearson's correlation analysis revealed that time spent daily with parents who smoke was significantly associated with maximum puff velocity (r=0.285, p=.019), a parameter predicting later pulmonary morbidity. ANOVAs, after a median split, were consistent with correlation analyses. There was a significant group effect on puff velocity (F(2,66)=5.197, p=.008); no significant relationship was found with puff volume (F(2,66)=.617) or puff duration (F(2,66)=.776). A post hoc Tukey HSD test indicated puff velocity was higher in the "high time spent" (M=54.37, SD=12.03) than in the "low time spent" group (M=45.59, SD=9.91) and in the group with non-smoking parents (M=44.96, SD=10.17). Future research with a larger non-treatment seeking sample of adolescents aimed at preventing tobacco smoking related diseases should further examine parental influences on adolescent smoking, including potential modeling effects.

Novel pharmacological approaches for treating tobacco dependence and withdrawal: current status

Increasing the diversity and availability of medications for the treatment of tobacco dependence and/or withdrawal, to aid in the achievement of smoking cessation, is crucial to meet the diverse needs of tobacco users. Despite a general awareness that smoking is harmful and widespread interest in smoking cessation, nearly 50 million adults in the US and 1.3 billion worldwide continue to smoke. Nicotine replacement therapies are effective in the treatment of tobacco dependence and withdrawal, but do not meet the needs of all tobacco users. Improvement of tobacco dependence and/or withdrawal treatments is likely to rely on novel pharmacological approaches that include new chemical entities and new formulations of current drugs. In addition, new indications for treating tobacco dependence and withdrawal show promise for reducing tobacco use and associated disease. This article focuses on a range of novel pharmacological approaches for the treatment of tobacco dependence and/or withdrawal, including oral and pulmonary nicotine delivery and the following non-nicotinic medications: antidepressants, an alpha4beta2 nicotine partial agonist, an alpha2-noradrenergic agonist, cytochrome P450 (CYP) 2A6 inhibitors, opioid antagonists and GABAergic medications. In addition to existing medications, this article addresses novel medications in the clinical development stage and those that have been evaluated previously. Novel medications in the clinical development stage include at least three nicotine vaccines and the cannabinoid receptor acting drug rimonabant. Medications evaluated previously include lobeline, mecamylamine and an anticholinergic drug regimen comprising atropine, scopolamine and chlorpromazine. Having not been approved by major drug regulatory authorities for the treatment of tobacco dependence and/or withdrawal, these medications have been evaluated in an experimental capacity.

Association of multiple behavioral risk factors with adolescents' willingness to engage in eHealth promotion

OBJECTIVE

This study examines adolescents' willingness to use the internet and other forms of technology for health promotion purposes (i.e., "eHealth promotion" willingness) and determines if a relationship exists between adolescents' behavioral risks and their eHealth promotion willingness.

METHODS

A total of 332 adolescents provided data at a routine medical check-up, including assessments of technology access, eHealth promotion willingness, and multiple behavioral risk factors for child- and adult-onset disease (body mass index, physical activity, smoking, sun protection, depression).

RESULTS

The level of access to technology among the sample was high, with moderate willingness to engage in eHealth promotion. After adjusting for adolescents' access to technology, the presence of multiple behavioral risk factors was positively associated with willingness to use technology for health promotion purposes (beta =.12, p =.03).

CONCLUSIONS

Adolescents with both single and multiple behavioral risk factors are in need of health promotion to prevent the onset of disease later in life. eHealth appears to be an acceptable and promising intervention approach with this population.

Cognitions about smoking and not smoking in adolescence

The theory of planned behavior identifies important proximal determinants of behavior, including attitude toward the behavior, perception of subjective norms exerted by significant others, and perception of perceived control over performance of the behavior. Because research in the planned behavior tradition has focused on desirable target behaviors, it is not clear how these determinants can best be conceptualized to account for adolescents' acquisition of health risk behaviors such as smoking. This cross-sectional study compared the explanatory power of planned behavior constructs assessed in relation to "smoking" and "not smoking" in a sample of 248 Dutch secondary students (aged 12 to 17 years; 56% girls). The results indicated that four variables--attitude toward smoking, perceived subjective norm, and perceived behavioral control over both smoking and not smoking--best explained the adolescents' smoking intentions and smoking behavior. Methodological and practical implications for smoking interventions are discussed.

Association between psychiatric disorders and smoking stages within a representative clinic sample of Puerto Rican adolescents

OBJECTIVE

We examined the prevalence of smoking behaviors and their association with specific psychiatric disorders in a representative sample of youth from behavioral health clinics in Puerto Rico.

METHOD

A complex sampling design was used to select the sample, and analyses were conducted to account for the unequal selection probability, stratification, and clustering. All analyses were weighted back to the clinical population from which they were drawn. Psychiatric and substance use disorders were assessed using the parent and youth versions of the Diagnostic Interview Schedule for Children, Version 4.0.

RESULTS

More than one third of the sample reported experience with cigarette smoking, and approximately one quarter reported smoking at least once per week (23.4%). As expected, the alcohol and drug use disorders demonstrated some of the strongest associations with individual smoking stages. These were the only disorders that remained significantly associated with nicotine dependence after controlling for comorbidity.

CONCLUSIONS

Our findings confirm the need for screening of smoking behavior and nicotine dependence in treatment settings and the integration of psychiatric/substance use treatments with smoking cessation.

Adolescent vs. adult-onset nicotine self-administration in male rats: duration of effect and differential nicotinic receptor correlates

Adolescence is the life stage when tobacco addiction typically begins. Adolescent neurobehavioral development may be altered by nicotine self-administration in a way that persistently potentiates addiction. Previously, we showed that female adolescent rats self-administer more nicotine than do adults and that the increased nicotine intake then persists through the transition to adulthood [E.D. Levin, A. Rezvani, D. Montoya, J. Rose, H. Swartzwelder, Adolescent-onset nicotine self-administration modeled in female rats, Psychopharmacology 169 (2003) 141-149.]. In the current study, male Sprague-Dawley rats were given access to nicotine via the standard operant IV self-administration procedure (nicotine bitartrate dose of 0.03 mg/kg/infusion). One group of male rats started during adolescence the other group started in young adulthood. After the end of the four-week period of self-administration brain regions of the rats were assessed for alpha4beta2 nicotinic receptor binding. We found that male rats, like females, show higher nicotine self-administration when starting during adolescence as compared to starting in adulthood (p<0.001). Indeed, the effect in adolescent males was even greater than that in females, with more than triple the rate of nicotine self-administration vs. the adult-onset group during the first 2 weeks. The adolescent onset nicotine-self-administering rats also had significantly greater high affinity nicotinic receptor binding in the midbrain and the striatum, whereas hippocampal binding did not differ between the age groups. Striatal values significantly correlated with nicotine self-administration during the first 2 weeks in the adult-onset group but not the adolescent-onset rats, suggesting that the differences in self-administration may depend in part on underlying disparities in synaptic responses to nicotine. After the initial 2 weeks, nicotine self-administration in male rats declined toward adult-like levels, as the adolescent rats approached adulthood. This study showed that adolescent male rats self-administer significantly more nicotine than do male adult rats, but that adolescent-onset nicotine self-administration in male rats declines over weeks of continued use to approach adult-onset levels. In a previous study, we found that female rats also show greater nicotine self-administration with adolescent onset vs. adult onset, but that the females continued higher rates of self-administration into adulthood. Our results thus reinforce the concept that the adolescent brain is unusually receptive to the effects of nicotine in a manner that reinforces the potential for addiction.

Chronic nicotine doses down-regulate PDE4 isoforms that are targets of antidepressants in adolescent female rats

BACKGROUND

Previous data in humans and animal models has suggested connections between anxiety, depression, smoking behavior, and nicotine dependence. The importance of these connections has been confirmed by clinical studies that led to the recent FDA approval of an anti-depressant (Zyban) for use in human smoking cessation programs. Other anti-depressants (such as rolipram) specifically inhibit PDE4 phosphodiesterases.

METHODS

We used DNA microarrays to discover gene expression changes in adolescent female rats following chronic nicotine treatments, and real-time PCR assays to confirm and extend those results.

RESULTS

We found a consistent decrease in the mRNA levels encoded by the Pde4b gene in nucleus accumbens, prefrontal cortex, and hippocampus of adolescent female rats treated with .24 mg/day nicotine, and in prefrontal cortex of adolescent female rats treated with .12 mg/day nicotine. We further show that each of these brain areas produced a different profile of Pde4b isoforms.

CONCLUSIONS

Chronic nicotine treatments produce a dose-dependent down-regulation of Pde4b, which may have an antidepressant effect. This is the first report of a link between nicotine dependence and phosphodiesterase gene expression. Our results also add to the complex interrelationships between smoking and schizophrenia, because mutations in the PDE4B gene are associated with schizophrenia.

Child and adolescent psychiatrists' practices in assisting their adolescent patients who smoke to quit smoking

OBJECTIVE

This national study examined the practices and perceptions of smoking cessation activities among child and adolescent psychiatrists.

METHOD

A random sample of child and adolescent psychiatrists was identified from the membership list of the American Academy of Child and Adolescent Psychiatry and was mailed a valid and reliable 34-item questionnaire.

RESULTS

A total of 184 responses (47%) were received. A plurality (48%) of psychiatrists reported being self-taught in smoking cessation techniques. A majority (67%) of psychiatrists were in the maintenance stage for asking about smoking status. However, only 19% consistently made attempts to assess willingness to quit, and 30% consistently gave messages urging the smoker to quit. The perceived number of barriers for addressing smoking was negatively correlated with psychiatrists' levels of confidence (r = -0.35, p <.001) and preparedness (r = -0.39, p <.001) in addressing smoking cessation. Estimations by the psychiatrists of youths who smoked were 61% of those with conduct disorders, 46% of those with schizophrenia, and 40% of those with attention-deficit/hyperactivity disorder.

CONCLUSION

Considering the perceived high rate of patient smoking and the lack of formal training in smoking cessation, more postgraduate education is needed to adequately prepare child and adolescent psychiatrists for addressing tobacco cessation.

Increased nicotine self-administration following prenatal exposure in female rats

There is a significant association between maternal cigarette smoking during pregnancy and greater subsequent risk of smoking in female offspring. In animal models, prenatal nicotine exposure causes persistent alterations in cholinergic and monoaminergic systems, both of which are important for nicotine actions underlying tobacco addiction. Accordingly, the current study was conducted to determine if there is a cause-and-effect relationship between prenatal nicotine exposure and nicotine self-administration starting in adolescence. Pregnant rats were administered nicotine (6 mg/kg/day) by osmotic minipump infusion throughout gestation and then, beginning in adolescence and continuing into adulthood, female offspring were given access to nicotine via a standard operant IV self-administration procedure (0.03 mg/kg/infusion). Gestational nicotine exposure did not alter the initial rate of nicotine self-administration. However, when animals underwent one week of forced abstinence and then had a second opportunity to self-administer nicotine, the prenatally-exposed animals showed a significantly greater rate of self-administration than did the controls. Prenatal nicotine exposure causes increased nicotine self-administration, which is revealed only when the animals are allowed to experience a period of nicotine abstinence. This supports a cause-and-effect relationship between the higher rates of smoking in the daughters of women who smoke cigarettes during pregnancy and implicates a role for nicotine in this effect. Our results further characterize the long-term liabilities of maternal smoking but also point to the potential liabilities of nicotine-based treatments for smoking cessation during pregnancy.

Some doubts about one of the largest smoking prevention programmes in Europe, the smokefree class competition

With over 600,000 participants in 16 countries, the smokefree class competition is one of the largest smoking prevention programmes in Europe. Participating classes that maintain a smoking prevalence usually below 10% are eligible for a contest and the winner is rewarded with money. There is however no convincing evidence that this competition has any effect on smoking prevalence beyond the short term, and this approach raises serious ethical issues. In particular, the central principle of this competition is to apply negative peer pressure upon teenage smokers. However, promoters of this competition have neglected to report the possible adverse consequences of using negative peer pressure upon smokers. This is a concern, because teenage smokers are more vulnerable than non-smokers, and they are at higher risk of suffering from psychological problems and school failure.