A natural experiment: Assessment of Danish high-school students' alcohol drinking patterns from 2014 and 2019 after the introduction of a common alcohol policy.

AIM: In this study, using national survey data from 2014 and 2019, we tested the hypothesis that students at schools who introduced a common alcohol policy in 2017 drank less than students at schools without a common policy. METHODS: We used survey data from 41 high schools that participated in the Danish National Youth Study in 2014 and 2019. We perceived the introduction of a common high-school alcohol policy in 2017 among local groups of high schools as a natural experiment and assessed it using difference-in-difference analyses. We assessed drinking patterns from 2014 and 2019 among students at schools with and without a common alcohol policy combined and stratified by sex in negative binominal regression and logistic regression models. Drinking patterns were measured as average weekly alcohol use, average alcohol intake at last school party, proportion of non-drinkers and frequent binge drinkers. RESULTS: Drinking patterns were similar among students in schools with and without a common alcohol policy. For example, among students at schools with a common alcohol policy, the average alcohol intake at the last school party among drinkers was 8.7 units in 2014 and 8.5 units in 2019, whereas average alcohol intake among students at schools without a common alcohol policy was 8.8 units in 2014 and 8.9 units in 2019 (p=0.413). CONCLUSIONS: No statistically significant effects were observed following the introduction of a common alcohol policy on students' drinking patterns, and alcohol consumption among high-school students was stable and remained high in 2014 and in 2019.

Alcohol use among adolescents during the first pandemic lockdown in Denmark, May 2020.

OBJECTIVE: As alcohol is often consumed for social purposes, we aimed to explore how restrictions during the first Danish COVID-19 lockdown affected the alcohol use among adolescents aged 15-20. METHOD: In May 2020, 11,596 15- to 20-year-olds from two subpopulations answered a survey regarding their alcohol use and social life, as well as changes to these, during the Danish lockdown. Using survey data from all participants, we performed a multinomial logistic regression to assess the association between determinants of alcohol use and perceived change in alcohol use during the Danish lockdown. We used longitudinal data from one subpopulation (n=1869) to perform negative binomial regressions exploring changes in frequency of alcohol use from 2019 to 2020. RESULTS: Of all participants, 59% drank less, 75% had fewer in-person social interactions and 56% met more frequently online during lockdown. Girls were more likely than boys to have a perceived decrease in alcohol use during lockdown (odds ratio (OR)=1.41; 95% confidence interval (CI) 1.27-1.56). A perceived decrease in in-person social interaction during lockdown was associated with less drinking (OR=2.27; 95% CI 1.98-2.61), while a perceived increase in in-person social interaction during lockdown was associated with more drinking (OR=1.42; 95% CI 1.11-1.82) compared to unchanged drinking behaviour and social interaction. CONCLUSIONS: Adolescents in Denmark drank less during the Danish lockdown than before. Findings indicate that there is a close relationship between in-person social interactions and frequency of drinking. Drinking episodes when meeting online were rare and were not unambiguously associated with changes in drinking during lockdown.

Symptoms of distress among young Danes during the national lockdown in May 2020.

Objectives of this study were to assess (1) prevalence of worries and symptoms of distress, and (2) perceived change in symptoms of distress by sociodemographic factors and preexisting vulnerabilities, among young Danes under the first COVID-19 related lockdown. Data were derived from online surveys, collected 7th-18th of May 2020. The study population included 11,245 young people (15-20 years of age), of which 1807 had participated in The Danish National Youth Study 2019 (DNYS19). Descriptive statistics and linear regressions analyses, including robust standard errors, were performed. All analyses were based on cross-sectional data, except analyses of preexisting vulnerabilities among responders from DNYS19. Few young people were very worried to get infected with coronavirus. Females reported a higher frequency of symptoms of distress than males. Perceived change in symptoms of distress, did not vary systematically based on age, cohabitation, nor physical health conditions. Individuals working, perceived a lower increase in symptoms of distress, than those studying etc. Females with symptoms of anxiety pre-pandemic, mental health disorders, and in families with economic hardship had a marginal higher perceived increase in symptoms of distress, than females without these difficulties. The tendencies were similar but nonsignificant among males, and for symptoms of depression pre-pandemic. In conclusion, during the lockdown, young females reported a higher frequency of symptoms of distress than males, and individuals with symptoms of anxiety pre-pandemic, mental health disorders, and in families with economic hardship were more likely to perceive the lockdown to be associated with an increase in symptoms of distress, than individuals without these difficulties.

The Danish National Youth Study 2019: study design and participant characteristics.

AIM: To present the study design, study population and questionnaire content of the Danish National Youth Study 2019, and to describe the differences between participants and non-participants regarding demographic and socioeconomic characteristics. METHOD: The Danish National Youth Study 2019 is a nationwide web-survey among high school students in Denmark. Data was collected from January to April 2019 through a self-administered questionnaire in the classroom. The questionnaire included 120 questions on, for example, physical and mental health, health behaviour and well-being. Data collection took place at 50 general high schools, 32 preparatory high schools, 15 commercial high school and 19 technical high schools. RESULTS: A total of 29,086 students participated (20,287 general high school students, 2,113 preparatory higher school students, 4027 commercial high school students and 2659 technical high school students) corresponding to 66% of the students in the 88 participating schools (31% of invited schools). Among students, 55% were female and the mean age was 17.8 years. Participants were more likely to be female, to be younger, to be of Danish origin, and have family disposable income in the highest quartile compared to non-participants. CONCLUSIONS: The Danish National Youth Study 2019 contributes to knowledge on high school students' health, health behaviour and well-being that can support health planning and prioritizing, through identification of specific risk groups at both local and national level. The study also offers great opportunities for future research as it provides possibility of linkage to various Danish national registers.

Are emotional symptoms and depression among young people with parental alcohol problems modified by socioeconomic position?

The aim was to test the hypothesis that parental alcohol problems and low socioeconomic position would be associated with higher odds ratio of emotional symptoms and depression as compared to high socioeconomic position and parental alcohol problems. Data came from Danish National Youth Study 2014, a web-based national survey with 75,853 high school and vocational school students participating, merged with register-data on family socioeconomic position. Multi-level logistic regression models (nesting participants within schools) were used to assess the association between perceived parental alcohol problems and frequent emotional symptoms and depression and effect modification by financial strains in the family, family income, or parental educational level. All analyses were adjusted for age, sex, education, immigration status, and cohabitation with parents. Young people with parental alcohol problems had higher odds ratio of experiencing frequent emotional symptoms (OR = 1.56 [1.46-1.66]) and depression (OR = 2.07 [1.88-2.28]), compared to young people without parental alcohol problems. There was no effect modification between severity of parental alcohol problems and the measures of socioeconomic position on the odds ratio of frequent emotional symptoms and depression. This study found that young people with parental alcohol problems in all social strata had higher odds ratios of frequent emotional symptoms and depression compared to young people without parental alcohol problems; the more severely they had been affected by parent's alcohol problems, the higher the odds ratios of frequent emotional symptoms and depression.

Does Class Proportion of Students with Non-Western Origin in High Schools Affect Drinking Habits Among Ethnic Danish Students?

AIM: the objective was to test the hypothesis that a higher proportion of students with non-Western origin in high school classes is associated with lower and less frequent alcohol consumption among ethnic Danish students. METHOD: data on country of origin was obtained from the Danish Civil Registration System, while information on drinking habits were derived from the Danish National Youth Study 2014. Multilevel zero-inflated binominal regression was used to assess the association between class proportion of students with non-Western origin and odds of non-drinking and mean weekly alcohol consumption, while multilevel logistic regression was used to assess the association with frequent binge drinking. RESULTS: a higher proportion of students with non-Western origin in class was associated with higher odds of non-drinking among ethnic Danish student in the same class. For example, ethnic Danish boys in classes with more than 15% of the students of non-Western origin had 77% higher odds of being non-drinkers, compared to ethnic Danish boys in classes where 0-5% had non-Western origin (OR: 1.77, 95% CI; 1.42-2.20). Among ethnic Danish students that did consume alcohol, class proportion of students with non-Western origin was not associated with weekly alcohol consumption, while a higher proportion of students with non-Western origin in class was associated with lower odds of frequent binge drinking. CONCLUSION: the downward drinking trend among adolescents in Western countries may be partly explained by the higher proportion of youth with non-Western origin, influencing the prevalence of drinking and frequency of binge drinking among adolescents in the ethnic majority population.

The Danish National Youth Study 2014: Study design, population characteristics and non-response analysis.

Aims: This paper aims to give a description of the Danish National Youth Study 2014 in terms of study design, study population and questionnaire content. The differences between participants and non-participants regarding socioeconomic characteristics are also described. Methods: The Danish National Youth Study 2014 was a web-based survey with data collected through self-completion questionnaires administered in the classroom. There were two questionnaires: one for students, with >250 core questions; and one for school leaders on the school environment. Data collection took place at 119 high schools and 10 vocational schools. Results: A total of 75,853 students participated (70,674 high school students and 5179 vocational school students). In the participating schools, 85% of high school students and 69% of vocational school students took part in the survey. A total of 166 school leaders responded. Among the high school students, 61% were girls, and among vocational school students, 24% were girls. The average age was 17.9 years for high school students and 20.9 years for vocational school students. Participants were more likely than non-participants to be of Danish origin and to have parents with higher educational levels and a higher disposable income. Conclusions: The Danish National Youth Study 2014 contributes to knowledge on adolescent health behaviour, health and well-being. It is unique in its size, diversity of questionnaire content, high participation rate and possibility of linkage to various national registers through the Danish Civil Registration System. The study offers great opportunities for health planning and a wide range of future research projects.

School factors and student drinking in high schools: a cross-sectional study of school policies and party regulation.

BACKGROUND: The effectiveness of school alcohol polices may be affected by the degree of strictness of rules, how they are implemented and enforced, students' perception of the rules and the consequences of breaking them. The aim of the study was to test the hypothesis that more liberal school alcohol policies, lack of knowledge of the alcohol policy, lower prices of alcohol at school parties, and liberal party regulation were associated with more drinking among high school students. METHODS: Participants were high school students (n = 68,898), participating in the Danish National Youth Study in 2014. Data came from questionnaires answered by high school students and school headmasters. Zero-inflated negative binominal regression with clustering of schools (n = 117) was used to assess the associations between alcohol policy reported by school headmaster and weekly alcohol intake reported by students. Multilevel negative binominal regression was used to assess the associations between alcohol price and liberal party regulations and units consumed at the last school party and units consumed at the school during the last school party. RESULTS: In general, school alcohol policies were not associated with high school students' weekly alcohol intake. High school students who did not know the school alcohol policy had a higher weekly alcohol intake (0.16 drinks 95% CL [0.11;0.21] p = 0.000), compared to students who knew the policy. Lower beer prices were positively associated with the number of drinks consumed at the school (p = 0.004), but not with the total amount consumed at the last school party (p = 0.728). High school students who agreed that students who were drunk could buy alcohol had a higher alcohol intake at the last school party (OR = 0.20 drinks 95% CL [0.18;0.21], p < 0.001) and drank more at the school (0.17 drinks 95% CL [0.15;0.18], p < 0.001) compared to those who did not agree that students who were drunk could buy alcohol. CONCLUSION: School alcohol policies were generally not associated with drinking among high school students, whereas students' lack of knowledge of the school policy was associated with a higher weekly alcohol intake. An addition, lower prices and liberal party regulation was associated with higher alcohol intake at school parties.

School- and class-level variation in self-harm, suicide ideation and suicide attempts in Danish high schools.

AIM: Strong associations have been found between being exposed to self-harm in family and friends and own self-harm in adolescence. Therefore, self-harm and suicide behaviour might tend to cluster within school and school classes. The aim of this study was to describe the prevalence, frequency and type of self-harm, suicide ideation and suicide attempts within Danish high schools and to test whether self-harm and suicide behaviour cluster in schools and school classes. METHODS: Data came from the Danish National Youth Study 2014, a national survey. The respective study included 66,284 high-school students nested in 117 schools and 3146 school classes. The prevalence and clustering of self-harm behaviour, ever and within the last year, type of self-harm (e.g. cutting, burning, scratching and hitting) and suicide ideation and suicide attempts were investigated. Multi-level logistic regression was applied to quantify clustering among participants within the same class and school. RESULTS: In total, 12,960 (20%) reported self-harm ever and 5706 (8.6%) within the last year. Prevalence was higher among girls than boys. Among girls, cutting (15%) and scratching (13%) was the most common type of self-harm, whereas among boys, hitting (6.7%) was most prevalent. The degree of clustering of self-harm and suicide behaviour was low, with school-level intra-class correlation coefficients (ICC) ranging from 0.8-1.8% and school class level ICC's from 4.3-6.8%. CONCLUSIONS: This study shows that self-harm was common, especially in girls. The degree of clustering of self-harm and suicide behaviour in school and school classes was low.

School and class-level variations and patterns of physical activity: a multilevel analysis of Danish high school students.

BACKGROUND: There is limited knowledge of physical activity (PA) patterns among high school students. High schools plays an important role as context for the students, but it is uncertain to what extent schools influence student participation in PA during leisure time. The purpose of this study is to describe patterns of PA and assess variations between schools and classes in PA, in a large cohort of Danish high school students. METHODS: Self-reported cross-sectional data came from The Danish National Youth Study, comprising a total of 70,674 students attending 119 different schools and 3213 classes. Multilevel logistic regressions were applied to evaluate the association between socio-demographic variables and patterns of PA, and to assess the impact of schools and classes on PA measures. RESULTS: Students whose parents have achieved a lower level of education, older students and girls of perceived ethnic minority generally participated less in several forms of PA during leisure time. Substantial variations between schools were observed in terms of participation in PA at school during leisure time and in terms of use of active transportation to and from school. The school-level accounted for 9% (intra-class correlation coefficient (ICC) = 0.09 (95% CI: 0.06-0.11)) and 8% (ICC = 0.08 (95% CI: 0.07-0.11)) of the variation for participation in PA during leisure time and active transportation. CONCLUSION: Overall, students whose parents achieved a lower level of education, older students and girls of perceived ethnic minority represent vulnerable groups in relation to participation in several forms of PA during leisure time. The ICCs indicate that schools, in particular, have the potential to influence participation in PA at school during leisure time and active transportation to and from school. Thus, high schools should encourage and facilitate activities aimed at engaging students in PA during leisure time as well as encourage active transportation.

Self-injury and suicide behavior among young people with perceived parental alcohol problems in Denmark: a school-based survey.

The aim of this study was to test the hypothesis that young people who perceive their parents to have alcohol problems are more likely to self-injure, have suicide ideation, and to attempt suicide than young people without parental alcohol problems. We also tested whether the association between parental alcohol problems and self-injury, suicide ideation, and suicide attempt among young people differed depending on the gender of the child and the parent. Data came from the Danish National Youth Study 2014, a web-based national survey. A total of 75,853 high school and vocational school students participated. Self-injury, suicidal ideation, and suicide attempts were outcomes and the main exposure variables were perceived parental alcohol problems, gender of the parent with alcohol problems, cohabitation with a parent with alcohol problems, and severity of the parents' alcohol problems. Young people with parental alcohol problems had higher odds of self-injury [boys: OR = 1.59 (95% CI 1.40-1.82); girls: OR = 1.84 (95% CI 1.69-1.99)], suicidal ideation [boys: OR = 1.81 (95% CI 1.59-2.06); girls: OR 1.74 (95% CI 1.59-1.89)], and suicide attempt [boys: OR = 2.10 (95% CI 1.63-2.71); girls: OR = 2.09 (95% CI 1.80-2.42)] compared to young people without parental alcohol problems. Girls with parental alcohol problems had higher odds of self-injury than boys with parental alcohol problems, whereas no gender differences were found for suicidal ideation and suicide attempts. Also no differences were found depending on the gender of the parent with alcohol problems. This study shows that young people with parental alcohol problems have higher odds of self-injury, suicide ideation, and suicide attempts.

Perceived parental alcohol problems and drinking patterns in youth: A cross-sectional study of 69,030 secondary education students in Denmark.

The aim of the study was to examine whether young people with parental alcohol problems have different drinking patterns than those without parental alcohol problems. Further, we examined whether the association between parental alcohol problems and young people's drinking patterns differed depending on the gender of the child and the parent, and whether more severe parental alcohol problems and cohabitation with the parent with alcohol problems was associated with earlier and heavier drinking patterns. Data came from the Danish National Youth Study 2014, a web-based national survey. 75,025 high school and vocational school students (15-25years) participated. Drinking patterns were investigated by the following outcomes: non-drinking, weekly alcohol consumption, frequent binge drinking, and early intoxication debut age. The main predictor variables were perceived parental alcohol problems, gender of the parent with alcohol problems, cohabitation with a parent with alcohol problems and severity of the parents' alcohol problems. Young people with parental alcohol problems had a higher weekly alcohol consumption (boys: 15.2 vs. 13.9 drinks per week; girls: 11.6 vs. 10.2 drinks per week), higher odds of early intoxication debut age (boys: OR=1.68 [95% CI 1.50-1.89]; girls: OR 1.95 [95% CI 1.79-2.14]), and more frequent binge drinking (boys, OR=1.16 [95% CI 1.04-1.29]; girls, OR=1.21 [95% CI 1.11-1.32]) compared to young people without parental alcohol problems. In conclusion, this study shows that young people with perceived parental alcohol problems have an earlier intoxication debut age, binge drink more frequently, and drink larger quantities per week than young people without perceived parental alcohol problems.

Implications of the decline in adolescent drinking on the experience of alcohol-related consequences in the Nordic countries: A study based on data from the ESPAD project.

Aims: The aim of this study was to investigate: (1) whether self-reported acute alcohol-related consequences among adolescents in the Nordic countries have declined in concert with the decline in alcohol consumption; (2) whether the relationship between alcohol consumption and alcohol-related consequences has strengthened; and (3) whether the decline in alcohol-related consequences can be attributed to the decline in alcohol consumption. Methods: Data are from the European School Survey Project on Alcohol and Other Drugs (ESPAD) cross-sectional surveys in 2007, 2011 and 2015. Participants were students aged 15-16 years in 2007 (n = 16,035), 2011 (n = 14,765) and 2015 (n = 13,517). Alcohol consumption variables included lifetime and 12-month alcohol use, volume ethanol at last drinking occasion and heavy episodic drinking in the past 30 days. Self-reported acute alcohol-related consequences were measured as a sum index of experiencing the following at least once within the last 12 months: (1) an accident or injury; (2) being victimised by robbery or theft; or (3) had trouble with the police. Results: For all alcohol indicators, adolescent alcohol use decreased between 2007 and 2015. The highest prevalence estimates were found in Denmark, and here only the number of current drinkers decreased significantly. In addition, a decreasing trend in self-reported acute alcohol-related consequences was observed. We did not find a strengthening of the alcohol consumption consequences association from 2007 to 2015, except in Iceland. When all surveys were combined, the decrease in alcohol-related consequences could be explained by a decrease in alcohol consumption. Conclusions: Overall, adolescents aged 15-16 years exhibited decreasing trends in both alcohol consumption, less markedly in Denmark, and in our sum index of alcohol-related consequences between 2007 and 2015. Except for Iceland, we found no support for a strengthening of the alcohol-consequences association with declining drinking among adolescents.

Prevalence of online sexual harassment and online bullying: a nationwide survey among high school students in Denmark.

Background: Using data from a nationwide survey among high school students in Denmark, the aim of the current study is to measure the prevalence of online bullying and online sexual harassment and assess gender and age differences in exposure. Methods: We used data from the Danish National Youth Study 2019, which is a nationwide web survey among high school students, including general, commercial, preparatory and technical high schools. Data were collected from January to April 2019 through a self-administered questionnaire in the classroom. A total of 29,086 students participated (response rate: 66%). The survey included questions about online sexual harassment (victimization and perpetration) and online bullying. Results: Approximately 11% of students reported receiving sexually offensive inquiries online, and about 10% received a sexual image/video of others without the subjects' consent. Additionally, 4% experienced that other people shared a sexual image/video of them without their consent within the last 12 months. The most common type of online bullying was feeling ignored by others online (25%), followed by someone spreading rumors or writing nasty things about them (13%), and receiving threats/unpleasant messages (12%). Gender results were mixed.

Effectiveness of proactive video therapy for problematic alcohol use on treatment initiation, compliance, and alcohol intake: a randomised controlled trial in Denmark.

BACKGROUND: Few people with problematic alcohol use reach treatment and dropout is frequent. Therapy for problematic alcohol use delivered via video conference (e-alcohol therapy) might overcome treatment barriers. In this randomised study, we tested whether proactive e-alcohol therapy outperformed face-to-face alcohol therapy (standard care) regarding treatment initiation, compliance, and weekly alcohol intake at 3-month and 12-month follow-up. METHODS: In this two-arm randomised controlled trial, we recruited individuals who had problematic alcohol use, defined as a score of 8 or more on the Alcohol Use Disorders Identification Test; were 18 years or older; and had access to a personal computer, smartphone, or tablet with internet access in Denmark through online advertisements. Participants were assigned to receive alcohol therapy delivered either face-to-face or via video conference. The number, frequency, and duration of therapy sessions were individualised in both groups. Data analysis was conducted using masked data. Primary analyses were based on an intention-to-treat sample. The study is registered with ClinicalTrials.gov (NCT03116282). FINDINGS: Between Jan 22, 2018, and June 29, 2020, 816 individuals signed up for the trial and 502 (63%) were assessed for eligibility. We randomly assigned 379 to proactive e-alcohol therapy (n=187) or standard care (n=192), of which, 170 (48%) participants were female and 186 (52%) were male. In the intervention group, more participants initiated treatment (155 [88%] of 177 vs 96 [54%] of 179; odds ratio [OR] 6·3; 95% CI 2·8 to 13·8; p<0·0001 at 3 months; 151 [85%] of 177 vs 115 [64%] of 179; OR 3·2; 95% CI 1·6 to 6·2; p=0·0007 at 12 months) and complied with treatment (130 [73%] of 177 vs 74 [41%] of 179; OR 4·0; 95% CI 2·2 to 7·2; p<0·0001 at 3 months; 140 [79%] of 177 vs 95 [53%] of 179; OR 3·4; 95% CI 1·8 to 6·3; p=0·0002 at 12 months). Weekly alcohol intake was significantly lower in the intervention group only after 3 months (13·0 standard drinks per week vs 21·3 standard drinks per week; adjusted difference -6·7; 95% CI -12·3 to -1·0; p=0·019). INTERPRETATION: Proactive e-alcohol therapy was associated with increased treatment initiation and compliance and is promising as an easily accessible and effective alcohol treatment for individuals with problematic alcohol use. FUNDING: TrygFonden.

Changes in co-use of alcohol and cannabis among Nordic adolescents in the 21st century: Results from the European School Survey Project on Alcohol and Other Drugs study.

INTRODUCTION: In the 21st century, there has been a decline in alcohol use among adolescents in most Nordic countries, while trends of cannabis use have diverged. We explore how alcohol and cannabis use, respectively, and co-use of the two substances, have changed among Nordic adolescents. Three hypotheses are used to frame the study: (i) cannabis use has substituted alcohol use; (ii) there has been a parallel decline in both substances; and/or (iii) there has been a 'hardening' of users, implying that alcohol users increasingly use cannabis. METHODS: Data from the European School Survey Project on Alcohol and Other Drugs, conducted among 15- to 16-year-olds in Denmark, Finland, Iceland, Norway and Sweden (N = 74,700, 49% boys), were used to explore trends of past-year alcohol and cannabis use in the period 2003-2019. RESULTS: The proportion of adolescents reporting alcohol use decreased significantly in all Nordic countries except Denmark. The proportion of those using cannabis only was low (0.0%-0.7%) and stable in all countries. The total number of substance use occasions declined among all adolescents in all countries but Denmark. Among alcohol users, cannabis use became increasingly prevalent in all countries but Denmark. DISCUSSION AND CONCLUSIONS: We found no support for the 'parallel decline hypothesis' in alcohol and cannabis use among Nordic adolescents. Partially in line with the 'substitution hypothesis', cannabis use accounted for an increasing proportion of all substance use occasions. Our results suggests that the co-use of alcohol and cannabis has become more common, thus also providing support to the 'hardening' hypothesis.

Perceived parental alcohol problems and later dropout and grade point average in high school: A register-based follow-up study.

INTRODUCTION: The aim of the study was to test the hypothesis that young people with perceived parental alcohol problems have higher dropout rates in high school and lower grade point average (GPA) at graduation compared to young people without perceived parental alcohol problems. METHODS: Data come from Danish National Youth Study 2014 (n = 62,171), merged with register-data on later dropout of high school and GPA. Multilevel Poisson regression models of incidence rates of dropout and multilevel linear models of GPA were used to assess the association with perceived parental alcohol problems. RESULTS: A total of 6.6% of the students perceived their parent(s) to have alcohol problems. Young people with perceived parental alcohol problems had higher dropout rate (girls incidence rate ratio 1.83; 95% confidence interval [1.62-2.06]); boys (incidence rate ratio 1.38; 95% confidence interval [1.17-1.64]) and lower grades (GPA: -0.24; 95% confidence interval [-0.32; -0.17]) compared to those without. There was no statistically significant difference between mother's and fathers' alcohol problems in the associations with dropout and GPA. DISCUSSION AND CONCLUSIONS: Perceived parental alcohol problems were associated with higher incidence rate ratio of dropout and lower grades within all categories of the socioeconomic factors. Our results show that young people with perceived parental alcohol problems have higher high school dropout rates and lower grades compared to those without perceived parental alcohol problems across gender and socioeconomic position. The results call for evidence-based interventions to support young people with parental alcohol problems in the educational system.

Alcohol consumption and well-being among 25,000 Danish high school students.

Excessive alcohol consumption among young people is an international public health concern, as alcohol is associated with a range of adverse short- and long-term consequences. Furthermore, alcohol consumption has been associated with well-being in young people, but the association depends on the chosen measure of well-being. The objective of this study was to assess how weekly alcohol consumption was associated with poor well-being (poor school enjoyment, social inclusion in school, mental well-being, life satisfaction, self-esteem, and self-efficacy, and experiencing loneliness). Cross-sectional data from the Danish National Youth Study 2019 was used (a total of 25,910 students aged 15-25 years). For most outcomes, there was a U-shaped association between weekly alcohol consumption and poor well-being e.g. students who never drank, students who only drank occasionally, and students who drank a lot (22 units of alcohol or more a week) had higher odds of poor well-being, compared to the reference group (1-7 units a week). This was the case for measures such as low school enjoyment (only females), poor mental well-being, low life satisfaction, low self-esteem (only females) and low self-efficacy (only males). Among females, odds of low self-efficacy was higher with higher weekly alcohol consumption. Higher weekly alcohol consumption was associated with lower odds of low social inclusion in school, experiencing loneliness often, and (among males) low self-esteem. Conclusively, well-being in general was lowest among never-, occasional- and heavy drinking students. Understanding these associations can help to decrease alcohol consumption and promote well-being among young students.

Social Disconnectedness, Loneliness, and Mental Health Among Adolescents in Danish High Schools: A Nationwide Cross-Sectional Study.

Background: Previous research has suggested that social disconnectedness experienced at school is linked to mental health problems, however, more research is needed to investigate (1) whether the accumulation of various types of social disconnectedness is associated with risk for mental health problems, and (2) whether loneliness is a mechanism that explains these associations. Methods: Using data from the Danish National Youth Study 2019 (UNG19), nation-wide cross-sectional data from 29,086 high school students in Denmark were analyzed to assess associations between social disconnectedness experienced at school (lack of classmate support, lack of teacher support, lack of class social cohesion, and not being part of the school community) and various mental health outcomes, as well as the mediating role of loneliness for each type of disconnectedness. Multilevel regression analyses were conducted to assess the associations. Results: Descriptive analyses suggest that 27.5% of Danish high school students experience at least one type of social disconnectedness at school. Each type of social disconnectedness was positively associated with mental health problems (depression symptoms, anxiety symptoms, stress, sleep problems, suicidal ideation, non-suicidal self-injury, eating disorder, body dissatisfaction, and low self-esteem) and negatively associated with mental well-being. In all cases, loneliness significantly mediated the associations. We found a clear dose-response pattern, where each addition in types of social disconnectedness was associated with (1) stronger negative coefficients with mental well-being and (2) stronger positive coefficients with mental health problems. Conclusion: Our results add to a large evidence-base suggesting that mental health problems among adolescents may be prevented by promoting social connectedness at school. More specifically, fostering social connectedness at school may prevent loneliness, which in turn may promote mental well-being and prevent mental health problems during the developmental stages of adolescence. It is important to note that focusing on single indicators of school social connectedness/disconnectedness would appear to be insufficient. Implications for practices within school settings to enhance social connectedness are discussed.

Study protocol for a cluster randomised controlled trial testing the effectiveness of the 'High schools High on life' intervention on reducing excessive drinking in Danish high schools.

INTRODUCTION: This paper describes the evaluation design of the 'High schools High on life' intervention; a school-based intervention to reduce excessive drinking among high school students in Denmark. The intervention includes a school environmental component to limit access to alcohol at school, a school-educational component to change social norms around alcohol among first year students and a parental component addressing parents' knowledge and attitudes towards alcohol. METHODS AND DESIGN: The study will employ a cluster randomised controlled study design and will include a random sample of 16 high schools randomly allocated 1:1 to either intervention or control group. Target group: first year high school students. Timeline: baseline survey: January to March 2019, collected as part of the Danish National Youth Study 2019. Delivery of intervention: April 2019 to March 2020. Follow-up survey: April to May 2020. PRIMARY OUTCOME MEASURE: 30% reduction in mean number of binge-drinking episodes (five or more alcoholic drinks on one occasion) within the last 30 days. SECONDARY OUTCOME MEASURES: proportion of students who drink alcohol, mean weekly alcohol consumption, alcohol intake at last school party, alcohol intake at the school during last school party, proportion of students who agree to be able to have fun at a party without drinking and the proportion of students who think alcohol plays a too dominant part at the school. Implementation will be monitored through process evaluation. ETHICS AND DISSEMINATION: The Scientific Ethics Committees for the Capital Region of Denmark has declared that the trial is not subject to notification (jnr. 19021957). The study is registered at the Research an Innovation Office at University of Southern Denmark (ref: 10.314) allowing collection of personal data. Results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03906500.