Marloes Kleinjan

Evaluation of a school-based depression prevention program among adolescents from low-income areas: a randomized controlled effectiveness trial

A randomized controlled trial was conducted among a potential high-risk group of 1,343 adolescents from low-income areas in The Netherlands to test the effectiveness of the depression prevention program Op Volle Kracht (OVK) as provided by teachers in a school setting. The results showed no main effect of the program on depressive symptoms at one-year follow-up. A moderation effect was found for parental psychopathology; adolescents who had parents with psychopathology and received the OVK program had less depressive symptoms compared to adolescents with parents with psychopathology in the control condition. No moderating effects on depressive symptoms were found for gender, ethnical background, and level of baseline depressive symptoms. An iatrogenic effect of the intervention was found on the secondary outcome of clinical depressive symptoms. Based on the low level of reported depressive symptoms at baseline, it seems that our sample might not meet the characteristics of a high-risk selective group for depressive symptoms. Therefore, no firm conclusions can be drawn about the selective potential of the OVK depression prevention program. In its current form, the OVK program should not be implemented on a large scale in the natural setting for non-high-risk adolescents. Future research should focus on high-risk participants, such as children of parents with psychopathology.

Factorial and Convergent Validity of Nicotine Dependence Measures in Adolescents: Toward a Multidimensional Approach

The present study investigated the possibility of forming a multidimensional scale for the measurement of nicotine dependence among adolescents, based on the modified Fagerström Tolerance Questionnaire (mFTQ) and the Hooked on Nicotine Checklist (HONC). A survey was conducted among 33 Dutch secondary schools, resulting in 2,041 smokers who completed the questionnaire. Motivation to quit and number of quit attempts were assessed and used as convergent construct variables for the construct of nicotine dependence. The findings show that combining the items of the mFTQ and the HONC results in three distinct dimensions: behavioral aspects of nicotine dependence, craving, and nervousness during abstinence. We examined this new multidimensional model in a second sample using confirmatory factor analysis. The new multidimensional measure fitted the data satisfactorily and showed good psychometric properties. Results of this study support the notion that nicotine dependence among adolescents is multidimensional.

A systematic review of the A118G (Asn40Asp) variant of OPRM1 in relation to smoking initiation, nicotine dependence and smoking cessation

Candidate gene studies on smoking behaviors mainly focused on dopaminergic and serotonergic genes, but genes within the µ-opioid system might also be involved. The A118G variant within the OPRM1 gene has been most often examined in relation to smoking, yielding inconsistent findings. It is largely unknown which of the alleles increases susceptibility for smoking behaviors. The aim of this review was to merge findings of OPRM1 gene studies in relation to smoking behaviors and to elaborate on the underlying biological mechanism of the A118G variant. It appeared that A118 was more likely to increase susceptibility to smoking behaviors than 118G, especially with regard to nicotine dependence, but less with smoking initiation and cessation. The proposed functioning of the OPRM1 gene is further explained.

Using ecological momentary assessment to test the effectiveness of a web-based brief alcohol intervention over time among heavy-drinking students: randomized controlled trial.

Background Web-based brief alcohol interventions are effective in reducing alcohol use among students when measured at limited follow-up time points. To date, no studies have tested Web-based brief alcohol intervention effectiveness over time by using a large number of measurements. Objective Testing whether the What Do You Drink (WDYD) Web-based brief alcohol intervention can sustain a reduction in alcohol use among heavy-drinking students aged 18-24 years at 1-, 3-, and 6-month follow-up intervals. Methods A purely Web-based, 2-arm, parallel-group randomized controlled trial applying an ecological momentary assessment approach with 30 weekly measurements was conducted in the Netherlands (2010-2011). Participants were recruited offline and online. A total of 907 participants were randomized into the experimental condition (n=456) including the single-session and fully automated WDYD intervention, or into the control condition (n=451) including assessment only. Weekly alcohol consumption and frequency of binge drinking were the self-assessed outcome measures. Results Attrition rates of the 907 participants were 110 (12.1%), 130 (14.3%), and 162 (17.9%) at 1-, 3-, and 6-month follow-up intervals, respectively. Latent growth curve analyses according to the intention-to-treat principle revealed that participants in the experimental condition had significantly lower weekly alcohol consumption compared to participants in the control condition that was sustained at 3-month follow-up (intercept=–2.60, P<.001; slope=0.16, P=.08). Additional linear regression analyses indicated that this intercept difference resulted from significantly higher levels of alcohol units per week for participants in the control condition compared to those in the experimental condition at 1-month (beta=–2.56, SE 0.74, Cohen’s d=0.20, P=.001), 3-month (beta=–1.76, SE 0.60, Cohen’s d=0.13, P=.003), and 6-month (beta=–1.21, SE 0.58, Cohen’s d=0.09, P=.04) follow-up intervals. Latent growth curve analyses further indicated that participants in the experimental condition had a significantly lower frequency of binge drinking compared to participants in the control condition that was sustained at 6-month follow-up (intercept=–0.14, P=.01; slope=0.004, P=.19). This intercept difference resulted from higher levels in this outcome for participants in the control condition relative to participants in the experimental condition at 1-month (beta=–1.15, SE 0.06, Cohen’s d=0.16, P=.01), 3-month (beta=–0.12, SE 0.05, Cohen’s d=0.09, P=.01), and 6-month (beta=–0.09, SE 0.05, Cohen’s d=0.03, P=.045) follow-up intervals. Conclusions The WDYD intervention was shown to be effective in preventing an increase in weekly alcohol consumption and frequency of binge drinking directly after the intervention. This effect was sustained 3 and 6 months after the intervention. Trial Registration Netherlands Trial Register NTR2665; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2665 (Archived by WebCite at http://webcitation.org/6LuQVn12M).

Mediational relations of substance use risk profiles, alcohol-related outcomes, and drinking motives among young adolescents in the Netherlands

AIM To examine the mediation by drinking motives of the association between personality traits (negative thinking, anxiety sensitivity, impulsivity, and sensation seeking) and alcohol frequency, binge drinking, and alcohol-related problems using a sample of students (n=3053) aged between 13 and 15, who reported lifetime use of alcohol. METHOD Structural equation modeling was used to examine the relationship between personality traits and alcohol-related outcomes. The Model Indirect approach was used to examine the hypothesized mediation by drinking motives of the association between personality traits and alcohol-related outcomes. RESULTS In this study among young adolescents, coping motives, social motives and enhancement motives played a prominent mediating role between personality and the alcohol outcomes. Multi-group analyses revealed that the role of drinking motives in the relation between personality and alcohol outcomes were largely similar between the sexes, though there were some differences found for binge drinking. More specifically, for young males, enhancement motives seems to play a more prominent mediation role between personality and binge drinking, while for young females, coping motives play a more mediating role between personality and binge drinking. Few mediation associations were found for conformity motives, and no relationships were found between anxiety sensitivity and drinking motives. DISCUSSION Already in early adolescence, personality traits are found to be associated with drinking motives, which in turn are related to alcohol use. This study provides indications that it is important to intervene in early adolescence with interventions focusing on personality traits in combination with drinking motives.

The Oxytocin Receptor Gene (OXTR) in Relation to State Levels of Loneliness in Adolescence: Evidence for Micro-Level Gene-Environment Interactions

Previous research has shown that the rs53576 variant of the oxytocin receptor gene (OXTR) is associated with trait levels of loneliness, but results are inconsistent. The aim of the present study is to examine micro-level effects of the OXTR rs53576 variant on state levels of loneliness in early adolescents. In addition, gene-environment interactions are examined between this OXTR variant and positive and negative perceptions of company. Data were collected in 278 adolescents (58% girls), by means of the Experience Sampling Method (ESM). Sampling periods consisted of six days with nine assessments per day. A relation was found between the OXTR rs53576 variant and state loneliness, in girls only. Girls carrying an A allele had higher levels of state loneliness than girls carrying the GG genotype. In addition, adolescents with an A allele were more affected by negative perceptions of company than GG carriers, on weekend days only. No significant gene-environment interactions were found with positive company. Adolescents carrying an A allele were more susceptible to negative environments during weekend days than GG carriers. Our findings emphasize the importance of operationalizing the phenotype and the environment accurately.

The Role of Explicit and Implicit Self-Esteem in Peer Modeling of Palatable Food Intake: A Study on Social Media Interaction among Youngsters

Objective This experimental study investigated the impact of peers on palatable food intake of youngsters within a social media setting. To determine whether this effect was moderated by self-esteem, the present study examined the roles of global explicit self-esteem (ESE), body esteem (BE) and implicit self-esteem (ISE). Methods Participants (N = 118; 38.1% boys; M age 11.14±.79) were asked to play a computer game while they believed to interact online with a same-sex normal-weight remote confederate (i.e., instructed peer) who ate either nothing, a small or large amount of candy. Results Participants modeled the candy intake of peers via a social media interaction, but this was qualified by their self-esteem. Participants with higher ISE adjusted their candy intake to that of a peer more closely than those with lower ISE when the confederate ate nothing compared to when eating a modest (β = .26, p = .05) or considerable amount of candy (kcal) (β = .32, p = .001). In contrast, participants with lower BE modeled peer intake more than those with higher BE when eating nothing compared to a considerable amount of candy (kcal) (β = .21, p = .02); ESE did not moderate social modeling behavior. In addition, participants with higher discrepant or “damaged” self-esteem (i.e., high ISE and low ESE) modeled peer intake more when the peer ate nothing or a modest amount compared to a substantial amount of candy (kcal) (β = −.24, p = .004; β = −.26, p<.0001, respectively). Conclusion Youngsters conform to the amount of palatable food eaten by peers through social media interaction. Those with lower body esteem or damaged self-esteem may be more at risk to peer influences on food intake.

Targeting young drinkers online: the effectiveness of a web-based brief alcohol intervention in reducing heavy drinking among college students: study protocol of a two-arm parallel group randomized controlled trial

BackgroundThe prevalence of heavy drinking among college students and its associated health related consequences highlights an urgent need for alcohol prevention programs targeting 18 to 24 year olds. Nevertheless, current alcohol prevention programs in the Netherlands pay surprisingly little attention to the drinking patterns of this specific age group. The study described in this protocol will test the effectiveness of a web-based brief alcohol intervention that is aimed at reducing alcohol use among heavy drinking college students aged 18 to 24 years old.Methods/DesignThe effectiveness of the What Do You Drink web-based brief alcohol intervention will be tested among 908 heavy drinking college students in a two-arm parallel group randomized controlled trial. Participants will be allocated at random to either the experimental (N = 454: web-based brief alcohol intervention) or control condition (N = 454: no intervention). The primary outcome measure will be the percentage of participants who drink within the normative limits of the Dutch National Health Council for low-risk drinking. These limits specify that, for heavy alcohol use, the mean consumption cannot exceed 14 or 21 glasses of standard alcohol units per week for females and males, respectively, while for binge drinking, the consumption cannot exceed five or more glasses of standard alcohol units on one drinking occasion at least once per week within one month and six months after the intervention. Reductions in mean weekly alcohol consumption and frequency of binge drinking are also primary outcome measures. Weekly Ecological Momentary Assessment will measure alcohol-related cognitions, that is, attitudes, self-efficacy, subjective norms and alcohol expectancies, which will be included as the secondary outcome measures.DiscussionThis study protocol describes the two-arm parallel group randomized controlled trial developed to evaluate the effectiveness of a web-based brief alcohol intervention. We expect a reduction of mean weekly alcohol consumption and frequency of binge drinking in the experimental condition compared to the control condition as a direct result of the intervention. If the website is effective, it will be implemented in alcohol prevention initiatives, which will facilitate the implementation of the protocol.Trial registrationNetherlands Trial Register NTR2665.

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.

Longitudinal associations between descriptive and injunctive norms of youngsters and heavy drinking and problem drinking in late adolescence

Cross-sectionally, social norms are related to heavy and problem drinking in late adolescence. A better understanding is needed regarding the longitudinal associations between social norms in younger populations and heavy and problem drinking over time. This study distinguished between descriptive (proximal reference group) and injunctive norms (proximal and distal reference groups). This study evaluated the perception of social norms in youngsters during early adolescence (13–15 years) and the contribution of these norms to heavy and problem drinking over a 4-year period. Adolescents (N = 428; 205 boys) participated in a prospective study with 5 annual waves. Regression analyses were conducted to examine whether descriptive and injunctive norms prospectively predict heavy and problem drinking. Descriptive and injunctive norms of the proximal, but not the distal reference group, predicted heavy drinking in late adolescence. Descriptive norms of the proximal reference group also predicted problem drinking in late adolescence. This study demonstrates the role of social norms in the prediction of heavy and problem drinking over time. Additionally, it illustrates the contribution of proximal rather than distal reference peers to heavy and problem drinking in late adolescence, and it suggests the relevance of targeting these norms in prevention research.