ObjectivesAdolescents spend increasingly more time on electronic devices, and sleep deficiency rising in adolescents constitutes a major public health concern. The aim of the present study was to investigate daytime screen use and use of electronic devices before bedtime in relation to sleep.DesignA large cross-sectional population-based survey study from 2012, the youth@hordaland study, in Hordaland County in Norway.SettingCross-sectional general community-based study.Participants9846 adolescents from three age cohorts aged 16–19. The main independent variables were type and frequency of electronic devices at bedtime and hours of screen-time during leisure time.OutcomesSleep variables calculated based on self-report including bedtime, rise time, time in bed, sleep duration, sleep onset latency and wake after sleep onset.ResultsAdolescents spent a large amount of time during the day and at bedtime using electronic devices. Daytime and bedtime use of electronic devices were both related to sleep measures, with an increased risk of short sleep duration, long sleep onset latency and increased sleep deficiency. A dose–response relationship emerged between sleep duration and use of electronic devices, exemplified by the association between PC use and risk of less than 5 h of sleep (OR=2.70, 95% CI 2.14 to 3.39), and comparable lower odds for 7–8 h of sleep (OR=1.64, 95% CI 1.38 to 1.96).ConclusionsUse of electronic devices is frequent in adolescence, during the day as well as at bedtime. The results demonstrate a negative relation between use of technology and sleep, suggesting that recommendations on healthy media use could include restrictions on electronic devices.

ObjectivesThe use of alcohol and drugs is prevalent among adolescents, but too little is known about the association between debut of alcohol and drug use, problematic use and concurrent mental health. The aim of the study was to investigate the cross-sectional association between debut of any alcohol or drug use and alcohol-related and drug-related problems and mental health. We also wanted to examine potential interactions between gender and age, and alcohol-related and drug-related variables.DesignCross-sectional study.SettingPopulation-based sample of Norwegian adolescents.ParticipantsData stem from the large population-based ung@hordaland study (N=9203), where all adolescents aged 17–19 years living in Hordaland county (Norway) were invited to participate. The main independent variables were debut of alcohol and drug use, alcohol consumption and the presence of alcohol and drug problems as measured by CRAFFT.OutcomesThe dependent variables were self-reported symptoms of anxiety, depression, inattention and hyperactivity. Statistical analyses included logistic regression models.ResultsDebut of alcohol and drug use were associated with symptoms of depression, inattention and hyperactivity (crude ORs 1.69–2.38, p<0.001), while only debut of drug use was associated with increased symptoms of anxiety (OR=1.33, CI 95% 1.05 to 1.68, p=0.017). Alcohol-related and drug-related problems as measured by CRAFFT were associated with all mental health problems (crude ORs 1.68–3.24, p<0.001). There was little evidence of any substantial age or gender confounding on the estimated associations between alcohol-related and drug-related measures and mental health problems.ConclusionsEarly debut of alcohol and drug use and drug problems is consistently associated with more symptoms of mental health problems, indicating that these factors are an important general indicator of mental health in adolescence.

No abstract

These results support a reciprocal relationship of drinking to positive expectancy, highlighting the importance both of expectancies on influencing drinking, and of early drinking experiences on the development of positive expectancies.

The results do not conclusively indicate a pattern of tracking. The tendency is, however, clear enough to support the assumption that dental health behavior continues during adolescence into adulthood.