Evelien A. P. Poelen

Alcohol Consumption in Movies and Adolescent Binge Drinking in 6 European Countries

OBJECTIVE: The goal of this study was to investigate whether the association between exposure to images of alcohol use in movies and binge drinking among adolescents is independent of cultural context. METHODS: A cross-sectional survey study in 6 European countries (Germany, Iceland, Italy, Netherlands, Poland, and Scotland) was conducted. A total of 16 551 pupils from 114 public schools with a mean (± SD) age of 13.4 (± 1.18) years participated. By using previously validated methods, exposure to alcohol use in movies was estimated from the 250 top-grossing movies of each country (years 2004−2009). Lifetime binge drinking was the main outcome measure. RESULTS: Overall, 27% of the sample had consumed >5 drinks on at least 1 occasion in their life. After controlling for age, gender, family affluence, school performance, television screen time, sensation seeking and rebelliousness, and frequency of drinking of peers, parents, and siblings, the adjusted β-coefficient for lifetime binge drinking in the entire sample was 0.12 (95% confidence interval: 0.10−0.14; P < .001). The crude relationship between movie alcohol use exposure and lifetime binge drinking was significant in all countries; after covariate adjustment, the relationship was still significant in 5 of 6 countries. A sensitivity analysis revealed that the association is content specific, as there was no significant association between lifetime binge drinking and exposure to smoking in movies. CONCLUSIONS: The link between alcohol use in movies and adolescent binge drinking was robust and seems relatively unaffected by cultural contexts.

Smoking in movies and adolescent smoking: cross-cultural study in six European countries

Aim To investigate whether the association between exposure to smoking in movies and smoking among youth is independent of cultural context. Method Cross-sectional survey of 16 551 pupils recruited in Germany, Iceland, Italy, the Netherlands, Poland and Scotland with a mean age of 13.4 years (SD=1.18) and an equal gender distribution. School-based surveys were conducted between November 2009 and June 2010. Using previously validated methods, exposure to movie smoking was estimated from the 250 top-grossing movies of each country (years 2004–2009) and related to ever smoking. Results Overall, 29% of the sample had tried smoking. The sample quartile (Q) of movie smoking exposure was significantly associated with the prevalence of ever smoking: 14% of adolescents in Q1 had tried smoking, 21% in Q2, 29% in Q3 and 36% in Q4. After controlling for age, gender, family affluence, school performance, television screen time, number of movies seen, sensation seeking and rebelliousness and smoking within the social environment (peers, parents and siblings), the adjusted ORs for having tried smoking in the entire sample were 1.3 (95% CI 1.1 to 1.5) for adolescents in Q2, 1.6 (95% CI 1.4 to 1.9) for Q3 and 1.7 (95% CI 1.4 to 2.0) for Q4 compared with Q1. The adjusted relationship between ever smoking and higher movie smoking exposure levels was significant in all countries with a non-linear association in Italy and Poland. Conclusions The link between smoking in movies and adolescent smoking is robust and transcends different cultural contexts. Limiting young peoples exposure to movie smoking could have important public health implications.

The Relative Contribution of Genes and Environment to Alcohol Use in Early Adolescents: Are Similar Factors Related to Initiation of Alcohol Use and Frequency of Drinking?

BACKGROUND The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual differences in initiation of alcohol use and frequency of drinking. METHODS Questionnaire data collected by the Netherlands Twin Register were available for 694 twin pairs aged of 12 to 15 years. Bivariate genetic model fitting analyses were conducted in mx. We modeled the variance of initiation of alcohol use and frequency of drinking as a function of three influences: genetic effects, common environmental effects, and unique environmental effects. Analyses were performed conditional on sex. RESULTS Findings indicated that genetic factors were most important for variation in early initiation of alcohol use (83% explained variance in males and 70% in females). There was a small contribution of common environment (2% in males, 19% in females). In contrast, common environmental factors explained most of the variation in frequency of drinking (82% in males and females). In males the association between initiation and frequency was explained by common environmental factors influencing both phenotypes. In females, there was a large contribution of common environmental factors that influenced frequency of drinking only. There was no evidence that different genetic or common environmental factors operated in males and females. CONCLUSION Different factors were involved in individual differences in early initiation of alcohol use and frequency of drinking once adolescents have started to use alcohol.

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).

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.

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.

Using Ecological Momentary Assessment in Testing the Effectiveness of an Alcohol Intervention: A Two-Arm Parallel Group Randomized Controlled Trial

Background Alcohol consumption of college students has a fluctuating nature, which might impact the measurement of intervention effects. By using 25 follow-up time-points, this study tested whether intervention effects are robust or might vary over time. Methods Data were used from a two-arm parallel group randomized controlled trial applying ecological momentary assessment (EMA) with 30 data time-points in total. Students between 18 and 24 years old who reported heavy drinking in the past six months and who were ready to change their alcohol consumption were randomly assigned to the experimental (n = 456: web-based brief alcohol intervention) and control condition (n = 451: no intervention). Outcome measures were weekly alcohol consumption, frequency of binge drinking, and heavy drinking status. Results According to the intention-to-treat principle, regression analyses revealed that intervention effects on alcohol consumption varied when exploring multiple follow-up time-points. Intervention effects were found for a) weekly alcohol consumption at 1, 2, 3, 4, and 7 weeks follow-up, b) frequency of binge drinking at 1, 2, 7, and 12 weeks follow-up, and c) heavy drinking status at 1, 2, 7, and 16 weeks follow-up. Conclusions This research showed that the commonly used one and six month follow-up time-points are relatively arbitrary and not using EMA might bring forth erroneous conclusions on the effectiveness of interventions. Therefore, future trials in alcohol prevention research and beyond are encouraged to apply EMA when assessing outcome measures and intervention effectiveness. Trial registration Netherlands Trial Register NTR2665

Dual growth of adolescent smoking and drinking: Evidence for an interaction between the mu-opioid receptor (OPRM1) A118G polymorphism and sex

Smoking and alcohol use often co‐occur during adolescence, but little is known about the codevelopment of these substances. In the search for etiological factors that help to explain the development of adolescent substance use patterns, studies have revealed substantial heritability for both alcohol use and smoking. In this regard, the µ‐opioid receptor gene (OPRM1, chromosome 6q24‐q25) has been linked to both substances. This study examined the predictive relationships between initial level and growth of smoking and drinking in 311 early adolescents (13–15 years old) over a 4‐year period. In addition, the effects of the A118G polymorphism of the OPRM1 gene on the initial values and the development over time of alcohol use and smoking were assessed. Finally, as prevalence and heritability estimates for both alcohol‐ and smoking‐related behaviors differ between males and females, OPRM1 by sex interactions were tested. We found that high initial levels of early adolescent alcohol consumption were related to a stronger increase in smoking levels over time. In contrast, high initial levels of smoking were not related to growth of alcohol use. No main OPRM1 effects were found, but sex‐specificity of the gene was found for smoking development. Male A‐allele carriers showed a faster development in smoking behavior, whereas in females, the G‐allele led to a faster development in smoking. Thus, in addition to high levels of alcohol as a risk factor for the development of smoking behavior, sex‐specific effects exist for OPRM1, which may additionally have consequences for the development of adolescent smoking.

High youth access to movies that contain smoking in Europe compared with the USA

Background Based on evidence that exposure to smoking in movies is associated with adolescent smoking, the WHO has called on countries to assign a rating that restricts youth access to such movies. Objective To evaluate youth access to movies that portray smoking in European countries and compare with that in the USA. Methods The authors identified the most commercially successful movies screened in six European countries (Germany, Iceland, Italy, the Netherlands, Poland and UK) and the USA between 2004 and 2009. The authors coded the 464 movies that were screened in both Europe and the USA according to whether or not they portrayed smoking. Results 87% of the movies were ‘youth’ rated in Europe (ratings board classification as suitable for those younger than 16 years) compared to only 67% in the USA (suitable for those younger than 17 years). Smoking was portrayed in 319 (69%) movies. 85% of the movies that portrayed smoking were ‘youth’ rated in Europe compared with only 59% in the USA (p<0.001). Conclusions Tobacco imagery is still common in popular films shown in European countries and the USA. None of the seven countries examined followed the WHO recommendations on restricting youth access to movies that portray smoking. Compared to the USA, European youths have access to substantially more movies in general, and this gives them access to more movies that portray smoking in particular.

The Effects of Music Genre on Young People's Alcohol Consumption: An Experimental Observational Study

The aim of this study was to test whether exposure to specific music genres in a social drinking setting leads to differences in drinking levels. An observational experimental design was used in which we invited peer groups of young adults into a bar lab, a lab which is furnished like an ordinary, small pub. Between two tasks, people had a break of 50 minutes in which they could order nonalcoholic and alcoholic beverages. During the break, participants were exposed to a specific music genre: popular, hard rock, rap, or classical music. Those groups who were exposed to classical music drank significantly more alcohol than those who were exposed to other music genres. This pattern is quite robust and does not depend on participants’ sex or age, drinking habits, own music preference, and relative importance of music in participants lives. The studys limitations are mentioned.