Disentangling the interplay between genes, cognitive skills, and educational level in adolescent and young adult smoking - The TRAILS study.

Recent studies suggest that smoking and lower educational attainment may have genetic influences in common. However, little is known about the mechanisms through which genetics contributes to educational inequalities in adolescent and young adult smoking. Common genetic liabilities may underlie cognitive skills associated with both smoking and education, such as IQ and effortful control, in line with indirect health-related selection explanations. Additionally, by affecting cognitive skills, genes may predict educational trajectories and hereby adolescents' social context, which may be associated with smoking, consistent with social causation explanations. Using data from the Dutch TRAILS Study (N = 1581), we estimated the extent to which polygenic scores (PGSs) for ever smoking regularly (PGSSMOK) and years of education (PGSEDU) predict IQ and effortful control, measured around age 11, and whether these cognitive skills then act as shared predictors of smoking and educational level around age 16, 19, 22, and 26. Second, we assessed if educational level mediated associations between PGSs and smoking. Both PGSs were associated with lower effortful control, and PGSEDU also with lower IQ. Lower IQ and effortful control, in turn, predicted having a lower educational level. However, neither of these cognitive skills were directly associated with smoking behaviour after controlling for covariates and PGSs. This suggests that IQ and effortful control are not shared predictors of smoking and education (i.e., no indirect health-related selection related to cognitive skills). Instead, PGSSMOK and PGSEDU, partly through their associations with lower cognitive skills, predicted selection into a lower educational track, which in turn was associated with more smoking, in line with social causation explanations. Our findings suggest that educational differences in the social context contribute to associations between genetic liabilities and educational inequalities in smoking.

Interplay between genetic risk and the parent environment in adolescence and substance use in young adulthood: A TRAILS study.

Many adolescents start using tobacco, alcohol, and cannabis. Genetic vulnerability, parent characteristics in young adolescence, and interaction (GxE) and correlation (rGE) between these factors could contribute to the development of substance use. Using prospective data from the TRacking Adolescent Individuals' Lives Survey (TRAILS; N = 1,645), we model latent parent characteristics in young adolescence to predict young adult substance use. Polygenic scores (PGS) are created based on genome-wide association studies (GWAS) for smoking, alcohol use, and cannabis use. Using structural equation modeling we model the direct, GxE, and rGE effects of parent factors and PGS on young adult smoking, alcohol use, and cannabis initiation. The PGS, parental involvement, parental substance use, and parent-child relationship quality predicted smoking. There was GxE such that the PGS amplified the effect of parental substance use on smoking. There was rGE between all parent factors and the smoking PGS. Alcohol use was not predicted by genetic or parent factors, nor by interplay. Cannabis initiation was predicted by the PGS and parental substance use, but there was no GxE or rGE. Genetic risk and parent factors are important predictors of substance use and show GxE and rGE in smoking. These findings can act as a starting point for identifying people at risk.

Socioeconomic inequalities in adolescent health behaviours across 32 different countries - The role of country-level social mobility.

Higher family affluence is associated with healthier behaviours in adolescents, but the strength of this association varies across countries. Differences in social mobility at the country-level, i.e. the extent to which adolescents develop a different socioeconomic status (SES) than their parents, may partially explain why the association between family affluence and adolescent health behaviours is stronger in some countries than in others. Using data from adolescents aged 11-15 years from 32 countries, participating in the 2017/2018 wave of the Health Behaviour in School-aged Children (HBSC) study (N = 185,086), we employed multilevel regression models with cross-level interactions to examine whether country-level social mobility moderates the association between family affluence and adolescent health behaviours (i.e. moderate-to-vigorous physical activity, vigorous physical activity, healthy and unhealthy foods consumption, having breakfast regularly, and weekly smoking). Higher family affluence was more strongly associated with higher levels of adolescent physical activity in countries characterized by high levels of social mobility. No cross-level interactions were found for any of the other health behaviours. Differences in social mobility at the country-level may contribute to cross-national variations in socioeconomic inequalities in adolescent physical activity. Further research can shed light on the mechanisms linking country-level social mobility to inequalities in adolescent physical activity to identify targets for policy and interventions.

Multiple health risk behaviors and mental health from a life course perspective: The Dutch TRAILS study.

We examined trajectories of multiple health risk behavior (MHRB) patterns throughout adolescence, and changes in mental health from childhood to young adulthood. Further, we assessed how continuity or onset of MHRBs overall were associated with subsequent changes in mental health, and whether this varied by type of MHRBs. We used six waves of the prospective Dutch TRAILS study (2001-2016; n = 2229), covering ages 11 until 23. We measured MHRBs (substance use: alcohol misuse, cannabis use, smoking; and obesity-related: overweight, physical inactivity, irregular breakfast intake) at three time points during adolescence. We assessed mental health as Youth/Adult Self-report total problems at ages 11 and 23. Latent class growth analyses and ANOVA were used to examine longitudinal trajectories and associations. We identified six developmental trajectories for the total of MHRBs and mental health. Trajectories varied regarding likelihood of MHRBs throughout adolescence, mental health at baseline, and changes in mental health problems in young adulthood. We found no associations for the continuity of overall MHRBs throughout adolescence, and neither for early, mid- or late onset, with changes in mental health problems in young adulthood. However, continuity of MHRBs in the obesity-related subgroup was significantly associated with an increase in mental health problems. Adolescents with the same MHRB patterns may, when reaching adulthood, have different levels of mental health problems, with mental health at age 11 being an important predictor. Further, involvement with obesity-related MHRBs continuously throughout adolescence is associated with increased mental health problems in young adulthood.

Secondary Effects of an Alcohol Prevention Program Targeting Students and/or Parents.

The secondary effects of an alcohol prevention program (PAS) on onset of weekly smoking and monthly cannabis use are examined among >3000 Dutch early adolescents (M age=12.64) randomized over four conditions: 1) parent intervention (PI), 2) student intervention (SI), 3) combined intervention (CI) and 4) control condition (CC). Rules about alcohol, alcohol use, and adolescents' self-control were investigated as possible mediators. PI had a marginal aversive effect, slightly increasing the risk of beginning to smoke at T1, and increased the likelihood of beginning to use cannabis use at T1 and T2. SI delayed the onset of monthly cannabis use at T3. CI increased the risk to use cannabis at T3. No mediational processes were found. In conclusion, though this study show mixed results, negative side effects of the PI were found, particularly at earlier ages. Moreover, these results indicate the need for multi-target interventions.

Early Adolescent Friendship Selection Based on Externalizing Behavior: the Moderating Role of Pubertal Development. The SNARE Study.

This study examined friendship (de-)selection processes in early adolescence. Pubertal development was examined as a potential moderator. It was expected that pubertal development would be associated with an increased tendency for adolescents to select their friends based on their similarities in externalizing behavior engagement (i.e., delinquency, alcohol use, and tobacco use). Data were used from the first three waves of the SNARE (Social Network Analysis of Risk behavior in Early adolescence) study (N = 1144; 50 % boys; M age = 12.7; SD = 0.47), including students who entered the first year of secondary school. The hypothesis was tested using Stochastic Actor-Based Modeling in SIENA. While taking the network structure into account, and controlling for peer influence effects, the results supported this hypothesis. Early adolescents with higher pubertal development were as likely as their peers to select friends based on similarity in externalizing behavior and especially likely to remain friends with peers who had a similar level of externalizing behavior, and thus break friendship ties with dissimilar friends in this respect. As early adolescents are actively engaged in reorganizing their social context, adolescents with a higher pubertal development are especially likely to lose friendships with peers who do not engage in externalizing behavior, thus losing an important source of adaptive social control (i.e., friends who do not engage in externalizing behavior).

Longitudinal patterns and predictors of multiple health risk behaviors among adolescents: The TRAILS study.

BACKGROUND: Most studies on multiple health risk behaviors among adolescents have cross-sectionally studied a limited number of health behaviors or determinants. PURPOSE: To examine the prevalence, longitudinal patterns and predictors of individual and multiple health risk behaviors among adolescents. METHODS: Eight health risk behaviors (no regular consumption of fruit, vegetables or breakfast, overweight or obesity, physical inactivity, smoking, alcohol use and cannabis use) were assessed in a prospective population study (second and third wave). Participants were assessed in three waves between ages 10 and 17 (2001-2008; n=2230). Multiple linear regression was used to assess the influence of gender, self-control, parental health risk behaviors, parental monitoring and socioeconomic factors on the number of health risk behaviors adjusted for preceding multiple health risk behaviors (analysis: 2013-2014). RESULTS: Rates of >5 health risk behaviors were high: 3.6% at age 13.5 and 10.2% at age 16. Smoking at age 13.5 was frequently associated with health risk behaviors at age 16. No regular consumption of fruit, vegetables and breakfast, overweight or obesity, physical inactivity and smoking predicted the co-occurrence of health risk behaviors at follow-up. Significant predictors of the development of multiple health risk behaviors were adolescents' levels of self-control, socioeconomic status and maternal smoking. CONCLUSIONS: Multiple health risk behaviors are common among adolescents. Individual and social factors predict changes in multiple health risk behaviors, showing that prevention targeting multiple risk behaviors is needed. Special attention should be paid to adolescents with low self-control and families with low socioeconomic status or a mother who smokes.

The Role of Self-Control and Early Adolescents' Friendships in the Development of Externalizing Behavior: The SNARE Study.

This social network study investigated the moderating role of self-control in the association between friendship and the development of externalizing behavior: Antisocial behavior, alcohol use, tobacco use. Previous studies have shown inconsistent findings, and did not control for possible friendship network or selection effects. We tested two complementary hypotheses: (1) That early-adolescents with low self-control develop externalizing behavior regardless of their friends' behavior, or (2) as a result of being influenced by their friends' externalizing behavior to a greater extent. Hypotheses were investigated using data from the SNARE (Social Network Analysis of Risk behavior in Early adolescence) study (N = 1144, 50 % boys, M age 12.7, SD = 0.47). We controlled for selection effects and the network structure, using a data-analysis package called SIENA. The main findings indicate that personal low self-control and friends' externalizing behaviors both predict early adolescents' increasing externalizing behaviors, but they do so independently. Therefore, interventions should focus on all early adolescents' with a lower self-control, rather than focus on those adolescents with a lower self-control who also have friends who engage in externalizing behavior.

Do online assessed self-report and behavioral measures of impulsivity-related constructs predict onset of substance use in adolescents?

INTRODUCTION: To prospectively predict the onset of use of alcohol, cigarettes and marijuana among Dutch adolescents, using behavioral and self-report measures of impulsivity-related facets. Specifically, we investigated whether behavioral measures of impulsivity predicted the onset of substance use above and beyond self-report measures of impulsivity and sensation seeking in an online sample. METHODS: Self-report and behavioral data from 284 adolescents (195 girls, mean age = 14.8 years, SD = 1.26) were collected at four time points over a period of two years, using an online survey system. Impulsivity-related facets were assessed at time point 1 with the Delay Discounting Task, the Balloon Analogue Risk Task and the Passive Avoidance Learning Task. We conducted logistic regression analysis to examine whether behavioral and self-report measures uniquely predicted onset of alcohol use, heavy episodic drinking, smoking and marijuana use. RESULTS: Onset of cigarette smoking was associated with behavioral assessment of impulsive decision making, but not after controlling for self-reported impulsivity and sensation seeking. Behavioral measures were sometimes associated with, but appeared not to prospectively predict, the onset of substance use in this online sample after controlling for self-report measures. CONCLUSIONS: Based on the present results, the added value of online behavioral assessment of impulsivity-related factors in the prediction of onset of substance use was not confirmed. We suggest that factors specific to each behavioral task underlie their lack of prediction and suggest that future research addresses limitations of current behavioral tasks to increase their validity in online testing.

Substance use outcomes in the Healthy School and Drugs program: results from a latent growth curve approach.

AIM: To assess the effectiveness of the Healthy School and Drugs (HSD) program for secondary schools on the development of substance use among Dutch early adolescents and to explore whether boys, adolescents of lower educational backgrounds, or adolescents high on personality risk traits, would benefit more from the HSD program than others. DESIGN: Randomized clustered trial with two intervention conditions (i.e., lessons and integral) among a general population of adolescents in the Netherlands. PARTICIPANTS: A total of 3784 students of 23 Dutch secondary schools. MEASUREMENTS: Structured digital questionnaires were administered pre-intervention and at 8, 20, and 32months follow-ups. The outcome measure was the rate of change in substance use across follow-ups. Differential effectiveness of the HSD program was examined for sex, educational level, and personality traits. FINDINGS: Our results show no HSD intervention effects on the development of substance use. Sex, education level, and personality characteristics of the participants did not moderate the intervention effects. CONCLUSION: The absence of effects of the Healthy School and Drugs program on the development of substance use indicates that the program should be renewed and redeveloped.

Cross-national evidence for the clustering and psychosocial correlates of adolescent risk behaviours in 27 countries.

BACKGROUND: According to Jessor's Problem Behaviour Theory (PBT) and Moffitt's theory of adolescence-limited antisocial behaviour, adolescent risk behaviours cluster and can be predicted by various psychosocial factors including parent, peer and school attachment. This study tested the potential influence of the sociocultural, or macro-level, environment on the clustering and correlates of adolescent risk behaviour across 27 European and North American countries. METHODS: Analyses were based on data from the 2009-10 Health Behaviour in School-aged Children (HBSC) study. Participants compromised 56,090 adolescents (M(age) = 15.5 years) who self-reported on substance use (tobacco, alcohol, cannabis) and early sexual activity as well as on psychosocial factors (parent, peer and school attachment). RESULTS: Multiple group confirmatory factor analyses (with country as grouping variable) showed that substance use and early sexual activity loaded on a single underlying factor across countries. In addition, multiple group path analyses (with country as grouping variable) showed that associations between this factor and parent, peer and school attachment were identical across countries. CONCLUSION: Cross-national consistencies exist in the clustering and psychosocial correlates of substance use and early sexual activity across western countries. While Jessor's PBT stresses the problematic aspects of adolescent risk behaviours, Moffitt emphasizes their normative character. Although the problematic nature of risk behaviours overall receives more attention in the literature, it is important to consider both perspectives to fully understand why they cluster and correlate with psychosocial factors. This is essential for the development and implementation of prevention programmes aimed at reducing adolescent risk behaviours across Europe and North America.

Long-term efficacy of nicotine replacement therapy for smoking cessation in adolescents: a randomized controlled trial.

BACKGROUND: A double-blind RCT on the short-term efficacy of nicotine patches compared to placebo patches among Dutch adolescents was conducted. The findings demonstrated that nicotine patches are efficacious for smoking cessation at end-of-treatment; however, only in highly compliant participants. We tested whether the effects of NRT also held in 6- (T7) and 12-month (T8) follow-up assessments. METHODS: Adolescents aged 12-18 years, who smoked at least seven cigarettes a day and who were motivated to quit smoking were recruited at school yards and randomly assigned to either a nicotine patch (n=182) or a placebo patch (n=180) condition according to a computer generated list. Participants (N=257, age: 16.7 ± 1.13 years) attended an information meeting followed by a 6- or 9-week treatment. Smoking cessation, compliance, and potential covariates were measured by means of online questionnaires. Smoking cessation at T8 was biochemically validated by saliva cotinine. RESULTS: At T7, 8.1% and 5.7% of participants were abstinent in the nicotine and placebo patch groups, respectively. At T8, abstinence was 4.4% and 6.6%, respectively. Intention-to-treat analyses showed no significant effects of NRT on abstinence rates at T7 (OR=1.54, 95% CI=0.57, 4.16) and validated abstinence rates at T8 (OR=0.64, 95% CI=0.21, 1.93) neither after considering compliance nor after adjusting for covariates. CONCLUSIONS: NRT fails in helping adolescents quit smoking at 6- and 12-month follow-ups. This finding suggests that a more intensive approach is needed to assist youngsters in their quit attempts.

Effectiveness of the 'Healthy School and Drugs' prevention programme on adolescents' substance use: a randomized clustered trial.

AIM: To evaluate the effectiveness of the Healthy School and Drugs programme on alcohol, tobacco and marijuana use among Dutch early adolescents. DESIGN: Randomized clustered trial with two intervention conditions (i.e. e-learning and integral). SETTING: General population of 11-15-year-old adolescents in the Netherlands. PARTICIPANTS: A total of 3784 students of 23 Dutch secondary schools. MEASUREMENTS: Structured digital questionnaires were administered pre-intervention and at 32 months follow-up. The primary outcome measures were new incidences of alcohol (life-time and 1-month prevalence), tobacco (life-time and 1-month prevalence) and marijuana use (life-time prevalence). FINDINGS: Main effect analyses showed no programme effects on incidences of alcohol consumption (life-time prevalence: e-learning condition: B = 0.102, P = 0.549; integral condition: B = -0.157, P = 0.351; 1-month prevalence: e-learning condition: B = 0.191, P = 0.288; integral condition: B = -0.140, P = 0.445), tobacco consumption (life-time prevalence: e-learning condition: B = 0.164, P = 0.444; integral condition: B = 0.160, P = 0.119; 1-month prevalence: e-learning condition: B = 0.088, P = 0.746; integral condition: B = 0.261, P = 0.093), or marijuana consumption (life-time prevalence: e-learning condition: B = 0.070, P = 0.732; integral condition: B = 0.186, P = 0.214). CONCLUSION: The non-significant impact of the Healthy School and Drugs programme (a Dutch school-based prevention programme for early adolescents) on incidences of alcohol, tobacco and marijuana use indicates that the programme is either ineffective or implemented inadequately.

Adolescents' use of nicotine replacement therapy for smoking cessation: predictors of compliance trajectories.

RATIONALE: Previous research has shown limited efficacy of nicotine replacement therapy (NRT) among adolescents and generally low compliance rates. As higher compliance rates are associated with improved abstinence rates, the present study examined predictors of NRT compliance. OBJECTIVES: This study aims to test whether different NRT compliance trajectories can be distinguished among adolescents, to test whether these trajectories can be predicted by demographic, smoking-related, and personality factors, and to examine abstinence rates for each trajectory. METHODS: Data were used from a randomized controlled trial that tested the efficacy of nicotine patches versus placebo patches among 265 Dutch adolescents. During NRT treatment, adolescents filled out six online questionnaires in which they reported on the number of days they used the patches. Predictors (i.e., demographic and smoking-related factors and personality characteristics) and end-of-treatment abstinence were also administered through these self-reports. Latent class growth analysis (LCGA) was used to analyze compliance data by classifying individuals into similar growth trajectories. RESULTS: Three compliance trajectories were found (i.e., "compliers" (n = 89), "moderate decreasers" (n = 41), and "strong decreasers" (n = 127)). The compliers can be characterized by higher levels of conscientiousness and agreeableness and lower levels of extraversion compared with the strong decreasers, and by higher levels of conscientiousness and education compared with the moderate decreasers. Among the compliers, a substantially higher percentage of adolescents achieved abstinence at end-of-treatment (10 %) compared with the moderate decreasers (3 %) and the strong decreasers (6 %). CONCLUSIONS: These findings could be the starting point for person-tailored interventions that aim to enhance NRT compliance rates among adolescents.

Short-term efficacy of nicotine replacement therapy for smoking cessation in adolescents: a randomized controlled trial.

The aim of this randomized, double-blind placebo-controlled clinical trial is to test the efficacy and safety of nicotine replacement therapy (NRT) in promoting end-of-treatment abstinence among adolescents and whether this relation is moderated by medication compliance. Participants (N=257, age: 16.7±1.13 years) attended an information meeting followed by a 6- or 9-week treatment. Self-reported smoking cessation, compliance, and side effects were measured by means of online questionnaires. Intent-to-treat analyses showed that independent of compliance, NRT is effective in promoting abstinence rates after 2 weeks (OR=2.02, 95% CI=1.11-3.69), but not end-of-treatment abstinence. However, end-of-treatment abstinence rates significantly increased in high-compliant (OR=1.09, 95% CI=1.01-1.17) and not in low-compliant participants. No serious adverse events were found. Future research is warranted to disentangle the process involving the decrease in abstinence rates and compliance rates from the third week after the quit date onwards.

Legal substance use and the development of a DSM-IV cannabis use disorder during adolescence: the TRAILS study.

AIMS: To examine whether early onset of tobacco or alcohol use, and continued use of tobacco or alcohol in early adolescence, are related to a higher likelihood of developing a cannabis use disorder during adolescence. DESIGN AND SETTING: Data were used from four consecutive assessment waves of the TRacking Adolescents' Individual Lives Survey (TRAILS), a general Dutch population study. TRAILS is an ongoing longitudinal study that will follow the same group of adolescents from the ages of 10 to 24 years. PARTICIPANTS: The sample consisted of 1108 (58% female) adolescents (mean ages at the four assessment waves are 11.09, 13.56, 16.27 and 19.05 years, respectively) MEASUREMENTS: Cannabis use disorders were assessed using the Composite International Diagnostic Interview 3.0 (CIDI). Adolescent tobacco and alcohol use were assessed using self-report questionnaires. FINDINGS: Early-onset tobacco use [odds ratio (OR) = 1.82, confidence interval (CI) = 1.05-3.14, P < 0.05], but not early-onset alcohol use (OR = 1.33, CI = 0.84-2.12, P > 0.05), was associated with a higher likelihood of developing a cannabis use disorder. Similarly, adolescents who reported continued use of tobacco (OR = 2.47, CI = 1.02-5.98, P < 0.05), but not continued use of alcohol (OR = 1.71, CI = 0.87-3.38, P > 0.05), were more likely to develop a cannabis use disorder. CONCLUSIONS: Early-onset and continued tobacco use appear to predict the development of a cannabis use disorder in adolescence, whereas early onset and continued alcohol use do not.

Cannabis use and vulnerability for psychosis in early adolescence--a TRAILS study.

AIMS: To examine the direction of the longitudinal association between vulnerability for psychosis and cannabis use throughout adolescence. DESIGN: Cross-lagged path analysis was used to identify the temporal order of vulnerability for psychosis and cannabis use, while controlling for gender, family psychopathology, alcohol use and tobacco use. SETTING: A large prospective population study of Dutch adolescents [the TRacking Adolescents' Individual Lives Survey (TRAILS) study]. PARTICIPANTS: A total of 2120 adolescents with assessments at (mean) age 13.6, age 16.3 and age 19.1. MEASUREMENTS: Vulnerability for psychosis at the three assessment points was represented by latent factors derived from scores on three scales of the Youth Self-Report and the Adult Self-Report, i.e. thought problems, social problems and attention problems. Participants self-reported on cannabis use during the past year at all three waves. FINDINGS: Significant associations (r = 0.12-0.23) were observed between psychosis vulnerability and cannabis use at all assessments. Also, cannabis use at age 16 predicted psychosis vulnerability at age 19 (Z = 2.6, P < 0.05). Furthermore, psychosis vulnerability at ages 13 (Z = 2.0, P < 0.05) and 16 (Z = 3.0, P < 0.05) predicted cannabis use at, respectively, ages 16 and 19. CONCLUSIONS: Cannabis use predicts psychosis vulnerability in adolescents and vice versa, which suggests that there is a bidirectional causal association between the two.

Young adult smoking in peer groups: an experimental observational study.

INTRODUCTION: The aim of this experimental observational study is to examine whether, in a group setting (same-sex triads), passive peer influence (imitation) in the context of homogeneous and heterogeneous (contradictory) behavior of peer models affects young adults' smoking behavior. METHODS: An experiment was conducted among 48 daily-smoking college and university students aged 17-25. Participants had to complete a 30-min music task with two same-sex confederates. We tested the following three conditions: (a) neither of the confederates is smoking, (b) one confederate is smoking and the other is not, and (c) both confederates are smoking. The primary outcome tested was the total number of cigarettes smoked during the task. RESULTS: Students in the condition with two smoking peer models and in the condition with one smoking peer model and one nonsmoking peer model smoked significantly more cigarettes than those in the condition with two nonsmoking peer models. However, results for the condition with two smoking peer models did not differ significantly from the condition with one smoking peer model and one nonsmoking peer model. CONCLUSIONS: Our findings show that in a group setting, the impact of the homogeneity of smoking peers on young adults' smoking behavior is not greater than the impact of the heterogeneity of smoking and nonsmoking peers. This would suggest that the smoking peer in the group has a greater impact on the daily-smoking young adult, thus reducing or even eliminating the protective effect of the nonsmoking peer model.

Effects of nicotine dependence and depressive symptoms on smoking cessation: a longitudinal study among adolescents.

INTRODUCTION: Nicotine dependence has been shown to hamper successful smoking cessation in adolescents. Nicotine dependence and depression are highly comorbid, but the relation between depression and smoking cessation is not yet fully understood. Therefore, the present study examines both the longitudinal reciprocal relation between nicotine dependence and depressive symptoms, and the longitudinal effect of these factors on successful smoking cessation and number of quit attempts. METHODS: A 2-wave longitudinal study was conducted among 535 adolescents aged 13-18. Written self-report questionnaires were administered in a classroom setting. Two models were tested, examining the mutual relation between nicotine dependence and depressive symptoms, as well as the predictive value of these factors on smoking cessation (n = 535), and number of quit attempts (n = 473) 1 year later. RESULTS: Adolescents with more depressive symptoms have significantly higher levels of nicotine dependence 1 year later. Higher levels of nicotine dependence negatively predicted subsequent successful smoking cessation, whereas depressive symptoms did not. In contrast, depressive symptoms predicted a higher number of unsuccessful quit attempts in the following year, whereas nicotine dependence did not. CONCLUSIONS: The findings suggest that adolescents tend to smoke cigarettes in order to diminish their depressive feelings, which might provide some support for the self-medication theory. Smoking cessation programs aiming at adolescents should not only focus on symptoms of nicotine dependence but should also pay attention to depressive feelings, since these feelings are related to a higher number of unsuccessful quit attempts.

The association between neurocognitive functioning and smoking in adolescence: the TRAILS study.

OBJECTIVE: This study examines the association between neurocognitive functioning and tobacco smoking in adolescence. METHOD: Data from three measurements of the longitudinal Tracking Adolescents' Individual Lives Survey (TRAILS), a large regional population-based cohort study of Dutch adolescents, were used. The first measurement took place in 2001-2002 (T1) when participants were age 11, with two follow-up measurements (2003-2004 and 2005-2007; T2 and T3, respectively). A total of 1,797 adolescents participated in all three waves. At T1, they performed a selection of tasks from the Amsterdam Neuropsychological Tasks program (De Sonneville, 1999), which enabled the assessment of the main aspects of neurocognitive functioning. Smoking was assessed with a self-report questionnaire at T1, T2, and T3. In the multivariate analyses we controlled for gender, age, socioeconomic status (SES) and baseline speed. RESULTS: Multivariate logistic regression analyses showed that poor sustained attention increased the likelihood that the adolescent would initiate smoking between T1 and T2. Low inhibition of prepotent responses increased the likelihood of smoking initiation between T1 and T3. An increased ability to inhibit biased response tendencies reduced the likelihood of being a daily smoker at T2. Poor sustained attention increased the likelihood of being a daily smoker at T3. CONCLUSION: Poor sustained attention and low inhibition predicted adolescent smoking. However, the proportion of the variance in smoking risk accounted for by these neurocognitive predictors proved to be small. Thus, although neurocognitive functioning is related to adolescent smoking, it seems to explain only a small part of why adolescents initiate and continue smoking.