It's past your bedtime, but does it matter anymore? How longitudinal changes in bedtime rules relate to adolescents' sleep.

This study investigated how changing or maintaining parent-set bedtimes over time relates to adolescents' sleep timing, latency, and duration. Adolescents (n = 2509; Mage = 12.6 [0.5] years; 47% m) self-reported their sleep patterns, and whether they had parent-set bedtimes on two separate occasions in 2019 (T1; 12.6 years) and 2020 (T2; 13.7 years). We identified four groups based on parent-set bedtimes: (1) bedtime rules at both T1 and T2 (46%, n = 1155), (2) no bedtime rules at T1 nor T2 (26%, n = 656), (3) bedtime rules at T1 but not T2 (19%, n = 472), (4) no bedtime rules at T1 but a parent-set bedtime at T2 (9%, n = 226). As expected, the entire sample showed that bedtimes generally became later and sleep duration shorter across adolescence, but the change differed among the groups. Adolescents whose parents introduced bedtime rules at T2 reported earlier bedtimes and longer sleep duration (~20 min) compared with adolescents with no bedtime rules at T2. Importantly, they no longer differed from adolescents who consistently had bedtimes across T1 and T2. There was no significant interaction for sleep latency, which declined at a similar rate for all groups. These results are the first to suggest that maintaining or re-introducing a parent-set bedtime may be possible and beneficial for adolescents' sleep.

Sleep duration and patterns in adolescents: correlates and the role of daily stressors.

OBJECTIVES: The first aim of this study was to assess the prevalence of sleep deficit in a large sample of adolescents. Second, the study aimed to assess whether short sleep duration in the sample was associated with emotional and behavioral problems. Lastly, the study aimed to investigate the association between daily stressors--bedtime activities and sleep duration. DESIGN: Cross-sectional survey. SETTING: The questionnaires were completed during school hours in 17 municipal junior high schools in Sweden. PARTICIPANTS: A total of 2767 adolescents aged 12 to 16 years, 48% girls. MEASUREMENTS AND RESULTS: Sleep measures included total sleep time (TST) for schooldays and weekends, obtained as combined measures of self-reported bed-time, wake-time, and sleep onset latency. We used the new National Sleep Foundation's guidelines to operationalize sleep duration. Overall 12% of younger adolescents (age 12-13 years) and 18% of older adolescents (14-16 years) slept less than recommended (TST < 7 hours). Adolescents reporting nonrecommended TST also reported more behavioral (ie, norm-breaking behaviors) and emotional problems (ie, depression, anxiety, and anger), with effects in the small-medium range. Finally, adolescents reporting bedtime arousal and use of information and communication technology in bed were more likely to report TST < 7 hours. Stress at home (for younger adolescents) and stress of school performance (for older adolescents) were also associated with TST less than 7 hours. CONCLUSIONS: The new National Sleep Foundation's recommendations were informative in this context. Future sleep interventions need to target barriers to good sleep practices, such as use of information and communication technology, stress, and worry that may contribute to arousal at bedtime.

Too tired for school? The effects of insomnia on absenteeism in adolescence.

OBJECTIVES: Sleep has important consequences for a person's daytime functioning. Numerous studies have shown that insomnia predicts work absenteeism and work disability in adults, but only a few studies have examined this association in adolescents. This study aims to explore whether symptoms of insomnia in adolescents predict school absenteeism 1 year later, over and above known psychological risk factors for absenteeism. DESIGN: The study used a longitudinal design with 2 measurement points over 1 year. SETTING: The students completed questionnaires during school hours at baseline and again at follow-up. PARTICIPANTS: Students in the 10th to 12th grades in a Swedish upper secondary school were followed prospectively for 1 year (age, 16-20 years; N = 353; 48.1% girls). MEASUREMENTS AND RESULTS: We used logistic regression analyses, controlling for the known effects of psychological factors, and arrived at a model elucidating the role of insomnia. That is, besides symptoms of insomnia, the model included previous absenteeism, alcohol intoxication, school-related social phobia, social anxiety, depressive symptoms, somatic symptoms, and bully victimization. Symptoms of insomnia predicted school absenteeism 1 year later, over and above known risk factors for absenteeism. Adolescents reporting severe symptoms of insomnia were almost 3 times more likely than adolescents reporting no or low symptoms to report problematic absenteeism 1 year later. We did not find any gender difference. CONCLUSIONS: Our findings underscore the importance of sleep problems on adolescents' daytime functioning as measured by school absenteeism. Therefore, sleep may be an important target for preventive interventions with adolescents.