Adolescent mental health and cardiorespiratory fitness: A comparison of two cohorts 12 years apart.

The aim of the study was to compare the mental health and cardiorespiratory fitness (CRF) of adolescents in two cross-sectional cohorts, one measured in 2003 and the other in 2015, both at age 15 and across sexes. The study also sought to estimate the association between mental health and CRF in the two cohorts and examine the relationship between the level of CRF and mental health in each cohort overall and by sex. Data from 443 participants born in 1988 (228 males, 215 females) and 303 participants born in 1999 (126 males, 177 females) were analyzed. Mental health was assessed using self-reports of body image, self-esteem, and symptoms of depression and anxiety. CRF was estimated using a maximal cycle ergometer test. From 2003 to 2015, body image scores improved (p = .043), self-esteem remained stable, and CRF declined significantly (p < .001). No self-esteem differences were observed between sexes in any cohort. Males had higher CRF and body image scores than females in both cohorts (p < .001 for all comparisons). Higher CRF correlated with fewer depressive symptoms across sexes and cohorts. Specifically, higher CRF was associated with anxiety in females and improved body image in males (2003) and both sexes (2015). Increased CRF was linked to higher self-esteem in females but not in males. Overall, higher CRF levels were associated with better mental health outcomes for both sexes. These results highlight the potential of improving adolescent mental health through increased physical fitness.

Social withdrawal behaviour in Nepalese infants and the relationship with future neurodevelopment; a longitudinal cohort study.

BACKGROUND: Social withdrawal in infants may be a signal of distress and a precursor for non-optimal development. OBJECTIVE: To examine the relationship between infant social withdrawal and neurodevelopment up to 4 years in Nepalese children. METHODS: A total of 597 Nepalese infants 6-11 months old were assessed with the modified Alarm Distress Baby Scale (m-ADBB), and of these, 527 with the Bayley Scales of Infant and Toddler Development 3rd edition (Bayley-III) during early childhood, and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-IV) and NEPSY-II subtests at 4 years. We examined whether social withdrawal defined by the m-ADBB was associated with neurodevelopmental scores in regression models. RESULTS: Children socially withdrawn in infancy had lower Bayley-III language scores (-2.6 (95% CI -4.5, -0.7)) in early childhood. This association seems to be driven by the expressive communication subscale (-0.7 (95% CI -1.0, -0.3)), but not the receptive communication subscale (-0.2 (95% CI -0.6, 0.1)). There were no differences in the other Bayley-III scores or the WPPSI-IV and NEPSY-II scores at 4 years in children who were socially withdrawn or not. CONCLUSION: Social withdrawal in infancy was reflected in early language development but not cognitive functioning at 4 years.

Sleep characteristics and changes in sleep patterns among infants in Bhaktapur, Nepal.

OBJECTIVE: Sleep undergoes major changes during the first year of life, but the characteristics of sleep among infants in low and middle-income countries are not well documented. This study describes sleep characteristics and changes in sleep patterns in infants at 6 and 12months of age from Bhaktapur, Nepal. METHODS: This was a community-based longitudinal study comprising 735 infants. Sleep characteristics were obtained by interview with the mother using the Brief Infant Sleep Questionnaires. The stability of sleep duration and night awakenings were estimated by logistic regression analysis. RESULTS: Cosleeping in the parent's bed at 6 and 12months of age was almost universal (>97%). At 6months of age, 254 (35%) and at 12months of age, 341 (46%) infants had a total 24-hour sleep duration <12 hours. Night awakenings >3 times per night were common (65%) both at 6 and 12months of age. Infants with frequent nightly awakenings at 6months had increased odds of frequent nightly awakenings at 12months (OR=2.2; 95% CI: 1.6, 2.9). Very few (<3%) mothers reported sleep problems in their infants at 6 and 12months of age. CONCLUSIONS: Cosleeping was almost universal among Nepalese infants, and very few of the mothers reported sleep problems in their infants. Infants at 6 and 12months had similar patterns for both sleep duration and nocturnal awakenings. For infants, there were increased odds of having similar sleep duration and nocturnal awakening at 6 and 12months.

Developmental trajectories of conduct problems and time-varying peer problems: the Bergen child study.

BACKGROUND: While it is increasingly acknowledged that conduct problems and peer problems often co-occur in development, less is known about the ways in which peer problems may alter the developmental course of conduct problems for distinct subgroups. METHODS: Using data from a large population-based study in Norway (the Bergen Child Study/youth@hordaland; 47.4% males), we estimated group-based trajectories of conduct problems and the presence of time-varying peer problems on the developmental progression of conduct problems between seven and 19 years of age. Risk factors for group membership were also examined. RESULTS: A 3-group model of conduct problems best fit the data (non-engagers, low-engagers, moderate-stable). The presence of peer problems increased the estimated level of conduct problems for both the low-engagers and moderate-stable groups across adolescence. No differences in conduct problems were observed when peer problems were present in childhood or preadolescence for these two groups, nor for the non-engagers group at any point. Being male, having lower perceived economic wellbeing, and lower levels of parental education predicted group membership for the moderate-stable group, whilst lower paternal education predicted membership for the low-engagers group. CONCLUSIONS: Support for developmental 'turning points' was found, suggesting that adolescence is a particularly salient time for those with conduct problems. In particular, the presence of peer problems can increase observed conduct problems at this stage in development.

Sleep duration and mental health in young adults.

BACKGROUND: The association between sleep duration and mental illness has been established in middle-aged and older populations, yet remains less explored in younger adults. Additionally, a common limitation to existing studies is the lack of statistical power to explore less common disorders. The purpose of this study was to examine sleep duration as a predictor for a range of mental disorders and well-being in a longitudinal sample of young adults. METHODS: Data were derived from two waves (w1, w2) of the SHoT survey, which invited all full-time university and college students in Norway. The response rates were 34.4 % (n = 62,498) in 2021 (w1) and 35.1 % (n = 59,554) 2022 (w2). This study utilized a nested longitudinal sample from both w1 and w2, encompassing 21,289 students. Demographics, sleep duration (w1), and mental health (w2) were measured by self-report questionnaires. Sex-stratified linear regression models and log-link binomial regression analyses were employed to determine the proportion and calculate the risk ratios, respectively, for mental illness across different sleep duration categories. RESULTS: The mean age of the sample was 24.8 years ± 4.5 years (w1). Students with shorter sleep durations, and to some degree longer sleep durations (illustrating a ᒐ-shaped association), exhibited a higher risk for all assessed mental disorders and well-being outcomes one year later, compared to students sleeping 8-9 h. The ᒐ-shaped trend was consistent for both female and male students. CONCLUSION: Sleep duration appears to be a transdiagnostic marker for mental health in young adults.

Parental unemployment and educational outcomes in late adolescence: the importance of family cohesion, parental education, and family income in a Norwegian study.

AIMS: The study aimed to investigate the association between parental unemployment and grade point average and school completion in adolescence, and the importance of family cohesion, parental education, and family income in explaining these associations. METHODS: Data stem from the Norwegian cross-sectional 2012 youth@hordaland-survey including 8437 adolescents (53.4% girls). Information on grade point average, school completion, parental education, and family income were retrieved from the National Education Database. Parental work status and family cohesion were assessed by adolescent self-report. RESULTS: Adolescents with at least one unemployed parent had lower grade point averages (3.49 compared with 3.92, P<0.001) and rates of school completion (71.9% compared with 86.6%, P<0.001) compared with adolescents with two working parents. The associations between parental unemployment and both grade point average (b = -0.22, 95% confidence interval -0.32, -0.12) and school completion (odds ratio 0.59, 95% confidence interval 0.46, 0.76) partly attenuated but remained significant when taking family cohesion, parental education, and family income into account. There was a significant interaction between parental unemployment and family cohesion on grade point average, in which the positive association between family cohesion and grade point average was weaker for adolescents with unemployed parents. CONCLUSIONS: Adolescents with parents outside of the workforce are at higher risk of poorer educational outcomes than peers with working parents. Combined with the positive associations between parental education, family cohesion, family income, and educational outcomes, this underscores the importance of parents for adolescent educational outcomes, and suggests that parents and the family situation should be considered when providing academic support for adolescents who struggle in upper secondary school.

Associations Between Distinct Trauma Classes and Mental Health Care Utilization in Norwegian Adolescents: A National Registry Study.

Adolescents who experience potentially traumatic experiences (PTEs) have an increased risk of psychopathology. PTEs often co-occur and may form interrelated patterns of exposure. This study investigated underlying classes of PTE exposure among Norwegian adolescent participants in the youth@hordaland study, and whether such classes were associated with contact with child and adolescent mental health services (CAMHS) and psychiatric diagnoses. The data stem from the population-based youth@hordaland study conducted in 2012 which was linked to the Norwegian Patient Registry (NPR, n = 8845). Exposure to PTEs was assessed by adolescent self-report whereas psychiatric disorders (Axis 1) were derived from the NPR. Latent Class Analysis was used to identify distinct classes of PTE exposure-patterns in the data. Logistic regression analyses were performed to investigate associations between classes of PTEs and contact with CAMHS and psychiatric diagnoses. Three classes of PTE exposure were identified based on model fit indices and theoretical considerations. Compared with participants in the low trauma class (88% of participants), those in the Situational-(6%) and Interpersonal trauma class (6%) had higher odds-ratios (ORs) for contact with CAMHS (OR = 2.27 (95% CI [1.78, 2.87])) and (OR = 3.26 (95% CI [2.61, 4.04])) respectively, and for being diagnosed with a psychiatric disorder in CAMHS (ORs ranged from 2.19 - 10.4) after adjusting for sex and parental education. There were more participants diagnosed with ADHD within the Interpersonal trauma class compared to the Situational trauma class when adjusting for sex and parental education (OR = 2.22 (95% CI [1.17, 4.40])). Three relatively homogeneous PTE classes, consisting of distinct patterns of trauma exposure were associated with a higher odds of contact with CAMHS and of being diagnosed with a psychiatric disorder in CAMHS. The study highlights the co-occurrence of PTEs and their impact across the diagnostic spectrum.

Prospective associations between adolescent risky substance use and school dropout and the role of externalising and internalising problems.

Background: The aim of the present study was to assess to what extent risky substance use (RSU) acts as an important risk factor for school dropout from upper secondary school in a prospective study of Norwegian adolescents, and how externalising and internalising mental health problems influenced this association. Methods: We used data from a large population-based survey (the youth@hordaland-survey), which included adolescents aged 16-19 years. The predictor variables were self-reported RSU. The survey was linked with prospective data from the Norwegian Education Database, following the adolescents to 21-23 years of age. The outcome variable was registry-based school dropout within five years after starting upper secondary school. The analyses were adjusted for sex, age, socioeconomic status, and externalising and internalising problems. Results: After adjustment for sociodemographic variables, all indicators of RSU were prospectively associated with school dropout (adjusted odds ratios 1.26-2.25; all p values <.01). While internalising problems only slightly changed these estimates, the associations were substantially attenuated by externalising problems. Still, all measures of RSU, except frequent alcohol intoxication, remained positively associated with school dropout in the fully adjusted models. For the youngest students, all associations between RSU and school dropout were significant. Conclusions: Adolescent RSU is a strong predictor for school dropout, and externalising problems explained a considerable proportion of this effect. Prevention efforts to reduce student substance could improve academic outcomes among upper secondary school students, and such efforts may benefit from also targeting co-occurring externalising problems.

Energy drink consumption and sleep parameters in college and university students: a national cross-sectional study.

OBJECTIVES: To investigate the frequency of energy drink (ED) consumption, and the association between ED consumption and selected sleep characteristics and parameters in Norwegian college and university students. We also explored whether these associations varied based on sex. DESIGN: Cross-sectional. SETTING: Data were gathered from the SHOT2022 study (Students' Health and Well-being Study), a national survey. PARTICIPANTS: 53 266 students, aged 18-35 years, enrolled in higher education in Norway (2022). MAIN OUTCOME MEASURES: Estimated marginal means were computed from general linear models investigating the association between ED consumption and continuous sleep outcomes, while log-link binomial regression analysis was used for dichotomous sleep outcomes of sleep measures. All models were adjusted for age. RESULTS: Among the participants, 4.7% of men and 3.3% of women reported consuming ED daily. The frequency of ED consumption was inversely associated with sleep duration and sleep efficiency, while a direct association was observed with the frequency of ED consumption and sleep patterns such as sleep onset latency and wake after sleep onset across sexes. The strongest association was found between daily ED consumption and short sleep duration where men had a risk ratio (RR) of 2.07; 95% CI 1.77 to 2.42, and women had a RR of 1.87; 95% CI 1.64 to 2.14. CONCLUSION: ED consumption was a strong determinant for negative sleep outcomes. Even small amounts of ED were associated with poorer sleep outcomes, which warrant more attention towards the consequences of consuming ED among college and university students.

Mental health problems and suicidal behavior from adolescence to young adulthood in college: linking two population-based studies.

It is well established that mental health problems are highly recurrent and persistent from childhood to adolescence, but less is known to what extent mental health problems also persist from adolescence into young adulthood. The aim of the current study was therefore to examine the chronicity and risk of mental health problems and suicidality from adolescence to young adulthood. Data stem from two Norwegian population-based studies conducted 6 years apart; the youth@hordaland study from 2012 (age 16-19) and the SHoT2018 study (age 22-25). These two data sources were linked to produce a longitudinal sample of 1257 individuals. A wide range of self-reported mental health and suicidality instruments (used both continuously and categorically) were analyzed using log-link binomial regression analysis, adjusting for age, sex, parental education, and financial problems. We found that high levels of mental health problems in late adolescence were a significant risk factor for reporting poor mental health 6 years later. Internalizing and externalizing problems in adolescence were associated with a 2.8-fold and 1.9-fold increased risk, respectively, of reporting a mental disorder 6 years later. Similarly, self-harm in adolescence was associated with a 2.1-fold increased risk of suicidal thoughts 6 years later. The magnitudes of the adjusted risk ratios were generally similar across the various mental health and suicidality measures used at the two assessment points. Adjustment for confounders did not, or only slightly, attenuate the risk ratios, and all associations remained statistically significant in the adjusted analyses. This longitudinal study provides new evidence of the chronicity of mental health problems and suicidality from adolescence to adulthood in Norway. The results emphasize the importance of early identification and timely interventions to reduce the prevalence and impact of mental health problems and suicidality.

Sleep and childhood maltreatment: A matched-control study of sleep characteristics in Norwegian 16-19-year-olds.

Sleep problems are an important but understudied health problem in adolescents exposed to childhood maltreatment. The current study aimed to examine sleep characteristics and insomnia in a population with maltreatment history and compare them to a general population sample of adolescents. Data from a sample of Norwegian 16-19-year-old adolescents with childhood maltreatment experiences (n = 62) were linked to an age- and sex-matched general population sample (n = 238). Independent samples t tests were used to compare the two groups on several detailed sleep parameters, while general linear models were used to control for mental health problems, assessed by the Strengths and Difficulties Questionnaire. Mental health was examined as a potential mediator between childhood maltreatment and sleep characteristics. Adolescents exposed to childhood maltreatment had longer sleep onset latency (1:15 h vs. 47 min, p < 0.001), longer wake after sleep onset (34 min vs. 15 min, p < 0.003), lower sleep efficiency in weekdays (77.8%, vs. 85%, p < 0.007), and lower sleep efficiency in weekends (81.8% vs. 88.9%, p < 0.001) than the reference group. Mental health problems fully mediated the association between childhood maltreatment exposure and longer sleep onset latency and wake after sleep onset. The rate of insomnia did not significantly differ between the groups. This study suggests that older adolescents exposed to childhood maltreatment have more sleep problems than the general adolescent population, and that these problems may be explained by co-existing mental health problems. These findings highlight the potential utility of assessing and providing sleep-focused treatment to adolescents with a history of childhood maltreatment and mental health problems.

Using Norwegian National Patient Registry data to understand associations between potentially traumatic life experiences and mental health care use in adolescence.

Exposure to potentially traumatic experiences (PTEs) is common among children and adolescents and associated with an increased risk of psychiatric diagnoses. This study aimed to ascertain how the number of PTEs differed across adolescent psychiatric diagnoses. Data on PTE exposure were derived from the youth@hordaland survey, and Axis 1 data were from the linked Norwegian National Patient Registry (NPR). Among 10,257 total adolescents, 9,555 (age range: 16-19 years, 53.9% female) consented to register linkage, 8,845 of whom were included in the analyses. Having contact with Child and Adolescent Mental Health Services (CAMHS) predicted more PTEs (estimated marginal mean [EMM] = 1.04, SE = 0.05) and exposure to two or more PTEs compared to having no CAMHS contact (EMM = 0.60) after adjusting for age, ethnicity, sex, and parental education. Adolescents diagnosed with attention-deficit/hyperactivity disorder, depression, trauma-related disorders, conduct disorder, and anxiety experienced significantly more PTEs (EMMs = 0.90-1.63) than those with no CAMHS contact (EMM = 0.57, SE = 0.01). All diagnostic categories except psychosis, autism spectrum disorders, and eating disorders had a significantly higher rate of PTEs compared with adolescents with no CAMHS contact. The study highlights the potential role of exposure to multiple PTEs as a transdiagnostic risk factor, although the level of risk varies between diagnoses.

Parental separation, negative life events and mental health problems in adolescence.

BACKGROUND: Parental separation is associated with mental health problems in adolescence. One suggested pathway for this association is through the accumulated exposure to stress and other negative life events. This study aimed to document the distribution of negative life events among adolescents with separated compared to non-separated parents, and to assess the direct and interactive associations between parental separation, negative life events, and mental health problems in adolescence. METHODS: Data stem from the cross-sectional population-based youth@hordaland study of adolescents (aged 16-19) conducted in Norway in 2012, providing self-reported information about parental separation, negative life events, and depression-, anxiety-, conduct-, and ADHD symptoms. Regression analyses were used to assess the direct and interactive associations between parental separation, negative life events, and mental health problems. RESULTS: Adolescents with separated parents had more mental health problems across all symptom scales compared to peers with non-separated parents, with standardized mean differences [SMDs] ranging from 0.15 to 0.20. Negative life events moderately attenuated these differences (reduced the SMDs with about 0.04-0.08, depending on the outcome). However, none of the interactions between parental separation and negative life events on mental health problems were statistically significant. CONCLUSIONS: Higher exposure to negative life events explains parts of the association between parental separation and mental health problems in adolescence. However, a parental separation does not seem to increase the vulnerability of the effects of negative life events on adolescents' mental health. Assessing exposure to negative life events is important when providing mental health services to adolescents, particularly to those who have parents separated.

Low Persistence of Inattention Symptoms From Childhood to Adolescence: A Population-Based Study.

OBJECTIVE: To investigate the persistence of dimensional measures of inattention in a population-based, gender-balanced sample of adolescents with parent reports of inattention from childhood and self-reports of inattention in adolescence. METHOD: Adolescents, 16-19 years old, completed the Adult ADHD Self Report Scale. Their parents completed the Swanson, Nolan, and Pelham Rating Scale-4th Edition when they were 7-9 and 11-13 years old. RESULTS: More severe inattention in boys than girls in childhood shifted to a female predominance in adolescence. The correlation between reports of inattention in childhood and adolescence was weak, with parent reports explaining only ~5% of the variance in the inattention score reported in adolescence. CONCLUSION: The weak association between inattention in childhood and adolescence is consistent with the emerging challenges associated with being an adolescent, but the impact of shifts in informants, gender and age on symtpom presentations should be investigated in future studies.

Sleep and dropout from upper secondary school: A register-linked study.

OBJECTIVE: The present study investigates the association between sleep in late adolescence and completion of upper secondary school. METHODS: The data are drawn from the youth@hordaland study, a large population-based study conducted in 2012, linked with official educational data in Norway (N = 8838). RESULTS: High school dropout was more prevalent among adolescents who had insomnia (20.6%) compared to those without insomnia (14.3%; adjusted risk ratios = 1.50; 95% confidence intervals: [2.19-2.92]). There was also a higher rate of school dropout among those who had symptoms of delayed sleep-wake phase (21%) compared to those without delayed sleep-wake phase (14.3%); adjusted risk ratios = 1.43, 95% confidence intervals: (1.28-1.59). School noncompleters were also characterized by reporting 44 minutes shorter sleep duration, longer sleep onset latency, and wake after sleep onset (both approx. 15 minutes) compared to school completers. CONCLUSION: The importance of sleep for high school dropout rates highlights the importance of including sleep as a risk indicator and a possible target for preventive interventions in late adolescence.

Parental separation and school dropout in adolescence.

AIMS: To document the association between parental separation and school dropout in adolescence and to examine the factors that may potentially account for this association. METHODS: Data stem from the large youth@hordaland study that was linked to the Norwegian National Educational Database to obtain objective measures of educational outcomes and disposable income (N = 8323). Logistic regression analysis was used to investigate the association between parental separation and school dropout. A Fairlie post-regression decomposition was used to examine the influence of parental education, household income, health complaints, family cohesion, and peer problems in explaining the association between parental separation and school dropout. RESULTS: Parental separation was associated with a higher odds ratio (OR) of school dropout in crude and adjusted (adjusted odds ratio (AOR)) analyses (OR=2.16, 95% confidence interval (CI) =1.90-2.45; AOR = 1.72, 95% CI = 1.50-2.00). About 31% of the higher odds of school dropout among adolescents with separated parents was explained by the covariates. The decomposition analysis suggested that parental education (43%) and disposable income (20%) accounted for most of the explained differences in school dropout. CONCLUSIONS: Adolescents with separated parents are at higher risk for not completing secondary education. Parental education and disposable income accounted for most of the explained differences in school dropout between the groups. Still, the majority of the difference in school dropout remained unaccounted for, indicating that the link between parental separation and school dropout is complex and likely influenced by multiple factors.

The effect of vitamin B12 supplementation during pregnancy on infant growth and development in Nepal: a community-based, double-blind, randomised, placebo-controlled trial.

BACKGROUND: Vitamin B12 is required for healthy infant growth and development, but low and marginal vitamin B12 status is endemic in low-income and middle-income countries. We aimed to measure the effect of vitamin B12 supplementation from early pregnancy until 6 months post partum on infant growth and neurodevelopment. METHODS: In this community-based, double-blind, placebo-controlled trial, we randomly assigned (1:1) 800 pregnant women (aged 20-40 years) who were up to 15 weeks pregnant-recruited from home visits and outpatient departments at three hospitals in Nepal-to daily supplementation with 50 µg oral vitamin B12 or placebo until 6 months postpartum. Independent scientists generated the list that linked allocation to participants' study identification number. Participants were masked to group assignment and all investigators were masked until data cleaning was completed. The primary outcomes were length-for-age Z score (LAZ) at age 12 months and the cognitive composite score of the Bayley Scales of Infant and Toddler Development (3rd edition) at age 6 months and 12 months. The primary and secondary outcomes, including adverse events, were assessed in the intention-to-treat population, for all participants with available outcome data. This trial is registered with ClinicalTrials.gov, NCT03071666. FINDINGS: 800 eligible pregnant women were enrolled in the trial between March 28, 2017, and Oct 15, 2020, with 400 women randomly assigned to each group. Follow-up was completed on May 18, 2022. At baseline, 569 (71%) of 800 women had plasma vitamin B12 indicating low or marginal status (<221 pmol/L). We found no effect of vitamin B12 on the primary outcomes. The mean LAZ at age 12 months were -0·57 (SD 1·03) in the B12 group and -0·55 (1.03) in the placebo group (366 infants in the vitamin B12 group vs 363 infants in the placebo group) with a mean difference of -0·02 (95% CI -0·16 to 0·13). The mean cognitive composite scores were 97·7 (SD 10·5) in the B12 group and 97·1 (10·2) in the placebo group, with a mean difference of 0·5 (95% CI -0·6 to 1·7) measured in 364 and 361 infants. Stillbirths or infant deaths occurred in three (1%) of 374 women in the vitamin B12 group and nine (2%) of 379 women in the placebo group. INTERPRETATION: Although vitamin B12 deficiency was prevalent in our study population and vitamin B12 supplementation from early pregnancy substantially improved vitamin B12 status, supplementation did not improve infant growth or neurodevelopment. Our findings support the current WHO recommendations of no routine vitamin B12 supplementation during pregnancy. FUNDING: Research Council of Norway.

Later school start time is associated with longer school day sleep duration and less social jetlag among Norwegian high school students: Results from a large-scale, cross-sectional study.

The present study explored the associations between school start time and sleep habits among older adolescents, and whether these associations depended on circadian preference. The sample comprised 4010 high school students aged 16-17 years who completed a web-based survey on habitual school start time, sleep, and health. The survey included the Munich ChronoType Questionnaire, and the short version of the Horne-Östberg Morningness-Eveningness Questionnaire. Students were categorised according to habitual school start time (before 08:00 hours, 08:00 hours, 08:15 hours, 08:30 hours or after 08:30 hours) and circadian preference (morning, intermediate or evening). Data were analysed using two-way analyses of variance (school start time × circadian preference) and linear regression analyses. Results showed an overall effect of school start time on school day sleep duration (main effect, p < 0.001), with the latest school starters having the longest, and the earliest school starters having the shortest sleep duration (7:03 hr versus 6:16 hr; Tukey HSD p < 0.001). Similarly, later school starters generally reported shorter social jetlag and later school day wake-up times than earlier starting students (both main effect p < 0.001). Circadian preference did not modify these associations (interaction effects p > 0.05). In the crude regression analysis, 15 min later school start was associated with 7.2 min more sleep (p < 0.001). School start time remained a significant predictor of school day sleep duration when adjusted for sex, parental educational level and circadian preference (p < 0.001). Results suggest that school start time is a significant predictor of school day sleep duration among adolescents.

Does It Matter Who You Provide Care for? Mental Health and Life Satisfaction in Young Adult Carers Associated with Type of Relationship and Illness Category-A National Student Survey.

There is limited knowledge on how caring contexts impact young adults providing informal care for persons with chronic conditions. This study examines associations between outcomes in young adult carers (YACs) and type of relationship (e.g., close or distant family member, partner, or someone outside the family) and type of illness in the care-receiver (e.g., mental, physical illness/disability, or substance abuse). A total of 37,731 students (age 18-25, mean 22.3 years, 68% females) in higher education in Norway completed a national survey on care responsibilities, hours of daily caring, relationship and type of illness, mental health problems (Hopkins Symptoms Checklist-25) and life satisfaction (Satisfaction With Life Scale). More mental health problems and lower life satisfaction were found among YACs compared to students without care responsibilities. The poorest outcomes were reported by YACs caring for a partner, followed by YACs caring for a close relative. Hours spent on daily caring was highest when caring for a partner. Poorer outcomes were reported by YACs caring for someone affected by substance abuse, followed by mental health problems and physical illness/disability. At-risk groups among YACs should be acknowledged and offered support. Future studies are needed to investigate the potential mechanism for the associations between care context variables and YAC outcomes.

The relationship between online communication and adolescents' mental health: Long-term evaluation between genders.

AIMS: In a relatively short time, online communication has become an important part of adolescents' lives, and concerns have been raised about its potential effects on mental health. The first aim was to compare mental health status and online communication in 15-year-old Icelanders born in 1988 and in 1994. The second aim was to assess whether the relationship between online communication and mental health has changed among 15-year-old Icelanders from 2003 to 2015 across genders. METHODS: Analysis used data from self-reports from 2003 (N=385, 51% males) and 2015 (N=302, 42% males). Mental health was assessed with subscales of Symptom Checklist 90 and online communications with self-reports. To evaluate the difference in anxiety and depression, a factorial analysis of variance was conducted between gender and years. Multigroup structural equation modelling was used to assess the change in the relationship between years. RESULTS: Symptoms of anxiety and depression remained unchanged for males. Symptoms of depression increased for females, while anxiety was stable between 2003 and 2015. In 2003, there was no relationship between online communication and mental health. However, in 2015, an association was found for females. CONCLUSIONS: Depression is getting worse for adolescent females, and an association between time spent online communicating and mental health emerged for them in 2015, which did not exist in 2003. These findings add to the possibility that online communication is harmful for mental health, but more detailed studies are still needed.