European Child & Adolescent Psychiatry

Background: Body-focused repetitive behaviours (BFRBs), including hair pulling, skin picking and nail biting, are common but under-recognised behaviours that often emerge during adolescence. Their prevalence, associated distress, and relationship with mental health and social factors remain poorly characterised. Methods: 5,437 adolescents aged 11-18 years reported engagement in BFRBs, associated distress, and functional interference as part of the 2025 OxWell Student Survey. Participants. Problematic BFRBs were defined as at least one BFRB with moderate or high distress. Associations with gender, neurodivergence, bullying, and internalising symptoms were examined using multivariable logistic regression. Results: Overall, 58.5% of participants reported at least one BFRB. Nail biting was most common (43.6%), followed by skin picking (31.3%) and hair pulling (14.5%). Among those with BFRBs, 22.2% reported moderate-to-high distress, and 3.3% of the total sample reported the highest level of distress. Co-occurrence was common: more than half of those with BFRBs reported multiple behaviours. BFRBs were more common and more distressing in girls and trans/gender-diverse participants than in boys. Problematic BFRBs showed strong associations with internalising symptoms (6.3% in the normal range vs 34.2% in the clinical range) and bullying (9.6% with no bullying vs 27.1% with >weekly bullying). Internalising symptoms were the strongest predictor in multivariable models (OR 1.97 per 10-point increase), alongside independent contributions from gender and frequent bullying. Conclusions: BFRBs are common in adolescents, frequently co-occur, and are strongly associated with emotional distress and social adversity. Recognition of distress, rather than behaviour alone, may be important for identifying unmet need and guiding intervention.

Background Although an expansive body of evidence exists on children's mental health during the COVID-19 pandemic, it is largely restricted to the early phases and lockdowns. This study examines longitudinal changes in child and youth mental health symptoms across two years of the COVID-19 pandemic, with data collection strategically timed to capture variability in pandemic restrictions. Methods A population-based longitudinal study of 1,261 children and youth aged 4-17 years followed prospectively from January 2021 to December 2022, with five waves of data collected in Ontario, Canada. Latent growth curve modelling was used to estimate trajectories of parent-reported mental health symptoms and identify baseline and time-varying covariates associated with variable trajectories. Findings Mental health symptoms were elevated and stable during lockdowns, followed by significant reductions as pandemic restrictions loosened, particularly for oppositional defiant and inattention/hyperactivity symptoms compared to internalizing symptoms. Children without pre-existing clinician diagnosed physical, mental or neurodevelopmental conditions and those not in lockdown at baseline demonstrated relative increases in mental health symptoms during lockdowns; and girls, compared to boys, demonstrated smaller reductions in internalizing symptoms as restrictions loosened. Concurrent and lagged associations between parental distress and children's mental health symptoms varied across the pandemic. Interpretation Variation in symptom trajectories by mental health domain, gender, pandemic restrictions and pre-existing diagnosed conditions underscores the need for tailored, equity-informed pandemic planning and response. Policies designed to optimize the balance between the need to reduce viral community transmission whilst limiting pandemic lockdowns may mitigate adverse impacts on child and youth mental health. Funding Ontario Ministry of Health

BackgroundScreen use is pervasive in childhood and adolescence, yet its role in antisocial behaviour (ASB) remains uncertain. While cross-sectional studies consistently link higher screen use to elevated ASB, longitudinal evidence is mixed, and few studies have controlled adequately for prior behaviour and genetic liability. Thus, it remains unclear whether these associations reflect prospective influences of screen exposure, or underlying vulnerabilities shared with ASB. We investigated whether screen use is a modifiable risk factor or a marker of underlying vulnerability. MethodsWe analysed data from up to 41,562 children in the Norwegian Mother, Father, and Child Cohort Study (MoBa). ASB traits and ICD-10-based conduct disorder (CD) diagnoses were assessed at ages 5, 8 and 14 years, together with screen use (total exposure and modality). Cross-sectional logistic regression models examined associations between screen use and ASB traits/CD at each age, adjusting for sex and parental education. Polygenic risk scores for ASB (PRSASB) were used to assess genetic susceptibility and gene-environment interplay. Lagged logistic models tested whether screen use predicted later ASB, adjusting for prior ASB. Linear mixed-effects models examined developmental patterns across age. ResultsHigher screen use was positively associated with ASB traits and CD across all ages, with dose-response patterns across screen-use modalities. Social media showed the strongest modality-specific association at adolescence. In lagged models, screen use did not predict later ASB after adjustment for prior ASB. Longitudinal models showed significant but attenuating associations across development. PRSASB was independently and additively associated with ASB outcomes but did not interact with screen use. ConclusionsWe found that higher screen use was consistently associated with antisocial outcomes across childhood and adolescence. However, the absence of prospective associations after accounting for prior behaviour, together with independent genetic contributions, suggests that screen use may be better understood as a marker of underlying vulnerability rather than an independent driver of antisocial development.

BackgroundA study conducted in Norway showed that the association between pupil mental health diagnoses and educational attainment has weakened over time. One possible explanation is that earlier detection of mental health problems in recent years has facilitated earlier treatment, intervention, and educational support that might improve academic outcomes. We investigated whether the weakening association between mental health and attainment could be replicated in England, and explained by earlier age at first diagnosis. MethodsThis was a secondary longitudinal data analysis of de-identified records from a secondary mental healthcare provider in England, which have been linked to the Department for Educations National Pupil Database. We included n=149,841 pupils residing in South East London, born 1993-2003, who completed their end-of-school exams 2009-2019. The main exposure variables were ADHD and internalising disorder diagnosis. In linear regressions, we investigated their associations with Year 11 attainment (typically assessed age 15-16 years), whether this was modified by birth year, and the role of age at first diagnosis. ResultsOn average, ADHD (n=844, 0.6%) and internalising disorder (n=2,523, 1.7%) were associated with lower Year 11 attainment. However, significant interactions between diagnosis and birth year suggested that pupils with these disorders showed increases in standardised exam scores over successive birth cohorts, resulting in a closing attainment gap over time. While age at first diagnosis became younger over the period, this did not confound the observed associations. ConclusionsWe replicated findings from Norway that suggest a narrowing attainment gap between those with and without ADHD and internalising disorder diagnoses. Building on this, we ruled out earlier age of diagnosis as a possible explanation for this phenomenon. With administrative data research growing internationally, we are increasingly able to replicate mental health and education trends in different countries, opening more opportunities for international collaboration.

IntroductionThe Nationwide Quality of Life Scale (NQLS) is a brief, mental-health focused quality of life (QoL) scale with seven items that are non-overlapping with symptom scales. We developed a parent version (P-NQLS), obtained national norms, and calculated psychometric properties for the P-NQLS. MethodsParents (N=2251) of children aged 6-18 years who were representative of the U.S. population on key demographics completed the P-NQLS along with measures of depression, suicidality, internalizing, externalizing, and attention symptoms. We assessed the P-NQLSs factor structure through exploratory factor analysis (EFA) and evaluated its internal reliability and convergent validity. Age- and sex-specific norms were established using GAMLSS with BCPE distributions and P-spline smoothers, with percentile curves and tables (5th-95th) provided. ResultsEFA suggested a one-factor solution for P-NQLS in the national sample. The scale showed good internal consistency (Cronbachs =0.85). P-NQLS total scores (M{+/-}SD=20.7{+/-}4.7, range=0-28, higher scores indicate higher QoL) were negatively correlated (all p<.0001) with depression (Pearsons r=-0.47), suicidality (r=-0.50), internalizing (r=-0.43), externalizing (r=-0.41), and attention (r=-0.37) symptoms. P-NQLS scores declined steadily with age in both sexes, with the most pronounced decreases (3-5 points) observed at lower percentiles (5th, 10th), suggesting greater age-related decline among children with lower baselines. Females scored slightly higher than males across most ages and percentile levels, though the differences were within one point. ConclusionsThe newly created P-NQLS, a 7-item parent-reported QoL scale with one underlying factor, demonstrates strong reliability and validity and has robust national norms for youth aged 6-18.

Background. Adolescence and young adulthood represent critical developmental stages during which mental disorders often emerge, with the potential to impede perceived quality of life. Spirituality (i.e., the search for the sacred) and self-regulation (i.e., intrinsic processes regulating emotions, thoughts, and behaviors) are recognized as protective factors for mental health. However, their dynamic interplay remains largely unexplored, particularly in real-life and in real-time among youths. This study, developed with the help of young partners, addresses this gap by investigating the longitudinal associations between spirituality, self-regulation, and mental health using an ecological momentary assessment (EMA) approach. Methods and analysis. We plan to recruit 120 adolescents and young adults (aged 16 to 20, expected attrition rate of 20%) from the community to complete a qualitative semi-structured interview assessing their beliefs, spiritual or religious activities, role models, and meaning in life. In addition, participants will take part in a multi-wave intensive longitudinal study. Trait-level assessments will be conducted at two time points, three months apart, to capture between-person differences. Additionally, to assess within-person dynamics, participants will complete EMA surveys four times daily over 10 consecutive days in two waves, also three months apart. Measures will include facets of spirituality (e.g., beliefs, meaning, collective consciousness), self-regulation (e.g., self-control, emotional regulation, impulsivity), as well as mental health indicators (emotional and behavioral symptoms) and quality of life. Qualitative data will be analyzed through a thematic analysis method, whereas quantitative associations will be assessed using Linear Mixed Models (LMM) and network analyses. Ethics and dissemination. Ethical approval has been obtained, and data collection begun in May 2025. Findings will be disseminated through open access peer-reviewed journals, conferences on adolescent mental health, and shared with practitioners, educators, and youth organizations. Results will also be made accessible to the general public. This study aims to inform personalized preventive and therapeutic interventions by elucidating real-time mechanisms linking spirituality, self-regulation, and mental health in youths.

ObjectiveThere is little longitudinal research investigating links between violence exposure and mental disorders among children in low- and middle-income countries (LMICs), despite high rates of violence. We examined cross-sectional and longitudinal violence-mental health associations among children in a large South African birth cohort, the Drakenstein Child Health Study, including direct clinical interviews capturing childrens mental disorders. MethodIn this birth cohort (N=974), we assessed lifetime violence exposure and four subtypes (witnessed community, community victimization, witnessed domestic, domestic victimization) at ages 4.5 and 8-years via caregiver reports. At 8-years, caregivers completed the Child Behaviour Checklist; and psychiatric disorders were assessed using the Mini-International Neuropsychiatric Interview for Children and Adolescents, a self-report measure. We tested for associations using linear/logistic regressions, adjusted for confounders. ResultsMost children (91%) had experienced violence by 8-years. Cross-sectionally, total violence exposure was associated with total (B =0.49 [95% CI 0.32, 0.66]), internalizing (0.32 [0.17, 0.47]), and externalizing problems (0.46 [0.31, 0.61]), and with increased odds of disorder at 8 years (aOR=1.09 [1.05, 1.13]). Longitudinally, total violence exposure up to 4.5-years was associated with total (B=0.27 [0.03, 0.52]), internalizing (0.24 [0.04. 0.44]), and externalizing scores (0.23 [0.008, 0.45]) at 8-years, but not with increased risk of psychiatric disorders. The strongest and most consistent associations were observed for domestic versus community violence subtypes. ConclusionOur strong cross-sectional but weaker longitudinal findings suggest that recent violence exposures may be more critical than early exposures for childrens mental health. Longitudinal exploration of other violence-affected LMIC populations is urgently needed.

ABSTRACT Background Liberian and Sierra Leonean children born during and after the 2012 UNHCR cessation clause, and the subsequent closure of the Oru refugee camp in Nigeria, have grown up in conditions of protracted displacement and de facto statelessness. Many of these children have been exposed to multiple forms of trauma, including witnessing violence as well as physical, emotional, and sexual adversities within a complex and resource-constrained environment. Many also experience cultural-linguistic disruptions, including heritage-language attrition and increased reliance on host-country languages, which may be associated with challenges in identity formation and social integration. However, little is known about how trauma exposure interacts with language-related factors to influence PTSD and complex PTSD (CPTSD)-related functional impairment among stateless refugee children. Methods Using a cross-sectional design, 320 children aged 6-17 years (180 Liberian, 140 Sierra Leonean) were assessed. Trauma exposure was measured using the Child and Adolescent Trauma Screen (CATS), and PTSD/CPTSD functional impairment using the International Trauma Questionnaire-Child and Adolescent Version (ITQ-CA). Heritage- and host-language proficiency were assessed using a structured sociolinguistic questionnaire. Multivariate covariance analyses were conducted using SPSS to examine main and interaction effects. Results Multivariate analyses revealed that poorer host-language communication was associated with higher PTSD-related functional impairment (F(3, 311) = 2.85, p = .038, partial eta-squared = .027), whereas CPTSD impairment was largely unaffected. Native-language proficiency also predicted PTSD impairment (F(3, 290) = 3.44, p = .017, partial eta-squared = .034), and children with low heritage-language skills, limited parental/home-language exposure, and no Nigerian-language use showed the highest CPTSD impairment. Emotional connection to the native language provided a modest protective effect. The combined heritage- and host-language exposure was linked to lower trauma-related functional impairment, particularly for children at higher risk of CPTSD. Witnessed trauma emerged as the strongest predictor of functional impairment among refugee children, with CPTSD outcomes showing greater sensitivity (partial eta-squared = .153) than PTSD (partial eta-squared = .076). Conclusions Heritage-language competence and bilingual proficiency were associated with reduced PTSD-related functional impairment, whereas CPTSD was more strongly shaped by cumulative relational trauma. These findings highlight the potential value of interventions that support bilingual development and heritage-language preservation as pathways to resilience among stateless refugee children. Keywords: Language attrition; bilingual competence; trauma exposure; refugee children; CPTSD; PTSD; functional impairment

Objective: ADHD has been associated with obesity indicators, including BMI, across the lifespan. A possible mechanism linking ADHD and BMI is binge eating. Previous research has found associations between ADHD, binge eating and BMI. However, the role of genetic and environmental influences on these associations remains unclear. Method: We utilized data from the Twins Early Development Study (TEDS), comprising 3,675 monozygotic and 7,063 dizygotic twin pairs. ADHD symptoms in childhood and adolescence were assessed using parent-reported questionnaires. Adult ADHD symptoms were measured using both self-report and parent-report questionnaires. Phenotypic mediation models examined whether binge eating mediated the association between ADHD and BMI, without controlling for genetic confounding. Subsequently, the etiological architecture underlying the associations among the three traits across childhood, adolescence, and adulthood were investigated by incorporating genetic and environmental influences into the models. Results: Binge eating significantly mediated the association between ADHD symptoms and BMI in both adolescence and adulthood. However, these mediation effects were no longer present once genetic and environmental influences were incorporated into the models. The best-fitting model in childhood, adolescence and adulthood was Cholesky decomposition models, where covariance between traits was explained by shared aetiology. Conclusions: This twin study reveals shared liability across ADHD, binge eating, and BMI. The mediating role of binge eating in the relationship between ADHD symptoms and BMI was largely confounded by shared genetic influences. Intervention strategies could focus more on common underlying behavioural and self-regulatory mechanisms across these traits, as well as placing more emphasis on symptom patterns within families.

BackgroundSuicide is one of the leading causes of death among adolescents. Suicidal thoughts and behaviors are significant risk factors for suicide, whilst depressive symptoms are significant risk factors for suicidal thoughts and behaviors. Multimodal school-based interventions that address these risk factors are considered the appropriate approach to suicide prevention. Method1,593 adolescents (aged 11-15 years) from 15 high schools in the Netherlands took part in the study, which was designed as a pragmatic cluster-randomized trial. The experimental condition consisted of (1) screening for depressive symptoms and suicidal thoughts and behaviors, followed by referral of those who scored positive; (2) gatekeeper training for school mentors; (3) a serious game to reduce stigma, promote health literacy and improve help seeking behavior; and (4) eight CBT-based sessions for adolescents with elevated depressive symptoms. The control group consisted of screening and the gatekeeper training. Both suicidal thoughts and behaviors and depressive symptoms were assessed at baseline, after 6 months and after 12-months follow-up. ResultsMultilevel mixed-model analysis revealed that, over the entire 12-month follow-up period, both suicidal thoughts and behaviors and depressive symptoms increased significantly in the experimental group, but not in the control group. No clinically relevant change was observed in either group. ConclusionsThe multimodal stepped-prevention program tested in the present study did not lead to a reduction in suicidal thoughts and behaviors or depressive symptoms. However, it is likely that the adverse impact of COVID-19-related school closures overwhelmed the programs effectiveness. Furthermore, few high-risk adolescents participated in the CBT-based sessions. Key Practitioner MessagesO_ST_ABSWhat is known?C_ST_ABSO_LISchool-based prevention programs aim to reduce suicidal thoughts, behaviors, and depressive symptoms among adolescents. C_LIO_LIMulti-modal interventions are increasingly promoted, but evidence of their effectiveness is limited under real-world conditions. C_LI What is new?O_LIThe multimodal stepped STORM program did not reduce STBs or depressive symptoms at 12-month follow-up; a small group-level increase was observed in the experimental group. C_LIO_LIParticipation in the indicated CBT-based module was low, revealing critical implementation gaps school programs. C_LI What is significant for clinical practice?O_LISchool-based programs should prioritize early identification with active referral, gatekeeper training. C_LIO_LIActive referral to a brief CBT-based intervention for high-risk students need to be implemented in close collaboration with both students and teachers to better assure its uptake C_LI

Objectives To explore caregiver and clinicians perspectives on implementing mental health conversations and supports for caregivers of children with chronic conditions in paediatric outpatient clinics. Specifically, views were sought on (a) screening approaches and measures (phase 1) and (b) how feedback and support could be provided to caregivers experiencing mental health difficulties (phase 2). Methods Caregivers and clinicians from two outpatient clinics (neuromuscular and diabetes) at a tertiary paediatric hospital in Melbourne, Australia participated in online focus groups in July and August 2024. Caregivers were recruited from outpatient clinics and clinicians were recruited via email. Both groups were combined for phase 1 before separating into breakout rooms for phase 2. Two authors conducted reflexive thematic analysis of transcripts using NVivo. Results Sixteen participants (caregivers n = 8; and clinicians n = 8) took part in in two semi-structured focus groups. Analysis generated two overarching domains, each comprising multiple themes. Domain 1, Addressing caregiver mental health, captured themes of overwhelm and invisibility, diverse caregiving roles, and the need for time and resources to support wellbeing conversations. Domain 2, Housing the mental health conversation, encompassed themes of screening preferences, caregiver agency in confidentiality, delivery of feedback, and access to tailored supports. Conclusions Caregivers and clinicians support routine caregiver mental health discussions in paediatric outpatient settings. Caregivers favour screening at diagnosis and key transitions, with clear, and actionable feedback delivered away from the child. Questions about record-keeping warrant further exploration, as do the perspectives of fathers.

Background: Attention Deficit Hyperactivity Disorder (ADHD) is characterized by persistent inattention, hyperactivity, and impulsivity. While documented in children, research on its persistence into young adulthood in Jordan remains scarce. This gap is critical given the cognitive demands of higher education. This study estimated attention deficit hyperactivity disorder (ADHD) symptom prevalence among Jordanian university students, examined associations with gender and academic performance, and identified barriers to mental health service accessibility. Methods: A descriptive cross-sectional study using web-based sampling recruited 389 university students (aged [&ge;] 18 years) from various Jordanian universities. Participants completed an online survey, incorporating the validated English and Arabic versions of the Adult ADHD Self-Report Scale (ASRS-v1.1) to assess symptom prevalence, alongside inquiries regarding demographics, academic history, and barriers to care. Results: The prevalence of probable ADHD was 37.5% (n=146). Males constituted a significantly higher proportion of positive cases (69.9%) compared to females (30.1%). A strong statistical association was found between positive ADHD screening and negative academic impact (p<0.001), as well as negative effects on emotional well-being (p<0.001). Comorbidities including anxiety disorders and emotional abuse were significantly linked to probable ADHD (p=0.019). Notably, positive-screened participants were significantly more likely to cite social stigma as a primary barrier to seeking professional help (p=0.024). Conclusion: Self-reported ADHD symptoms are highly prevalent among Jordanian university students, correlating with substantial academic underachievement and emotional dysfunction. These findings highlight an urgent need for targeted university-based screening programs, academic accommodations, and de-stigmatization campaigns to facilitate early intervention and improve educational outcomes in this population.

Objective: Cross-sectional studies indicate associations between self-reported social media use and adolescent wellbeing outcomes. We aimed to evaluate longitudinal associations of objectively measured smartphone and social media use with psychosocial wellbeing. Design: Observational study with one year of follow-up Setting: High schools in Finland from 2022 to 2023 Population: 259 adolescent girls (mean age 16.3 years at baseline) Main outcome measures: screenshots depicting smartphone and social media use, Bergen Social Media Addiction Scale (BSMAS), Generalized Anxiety Disorder-7 questionnaire, Body Appreciation Scale 2 (BAS-2) and visual analogue scales (VAS) of mood, tiredness, and loneliness Results: Across one year of follow-up, anxiety, body appreciation, and mood improved, but possible social media addiction increased from 15% to 17%. Social media addiction at baseline was associated with increased anxiety (r=0.29, p<0.001), lower body appreciation (r=-0.15, p=0.022), and more loneliness (r=0.20, p=0.001) at follow-up. Anxiety at baseline was associated with social media addiction at follow-up (r=0.19, p=0.005). The highest quartile of TikTok users reported more social media addiction (BSMAS 19 [IQR 16-21] vs. 17 [IQR 14-20]; p=0.009) and lower body appreciation (BAS-2 32 [IQR 28-38] vs. 35 [IQR 29-40]; p=0.003) than did others. The highest quartile of Snapchat users reported more social media addiction (BSMAS 19 [IQR 15-21] vs. 17 [IQR 14-20]; p=0.007) and tiredness (VAS 21 [IQR 13-32] vs. 26 [IQR 15-35]; p=0.049) than did others. Conclusions: Consistent with cross-sectional studies, social media addiction was associated with poorer psychosocial outcomes across follow-up. Policies to protect adolescents from social media addiction are urgently needed.

BackgroundA range of rare chromosomal micro-deletions or -duplications (Copy Number Variants - CNVs) are associated with high risk of neurodevelopmental and mental health conditions (ND-CNVs). There is great individual variability in outcomes, but we lack insights into the contributing social factors, including family functioning. MethodsCaregivers of 598 children and young people (CYP) with a range of 16 ND-CNVs and 222 siblings without ND-CNVs (controls) completed questionnaires on overall family climate (cohesion and conflict) as well as caregiver-CYP relationship warmth and hostility and took part in a research diagnostic interview about CYPs psychiatric symptoms. CYPs intelligence quotient (IQ) was also measured. ResultsComparisons with published data from neurotypical families indicated that families affected by ND-CNVs are characterised by higher family cohesion and conflict as well as lower caregiver-CYP warmth and hostility. Symptoms of oppositional defiant disorder reduced more steeply in CYP with ND-CNVs compared to controls with increasing family cohesion (interaction effect: {beta} = -0.14, p = 4.65 x 10-{superscript 2}). In contrast, they rose more steeply with increasing family conflict (interaction effect: {beta} = 0.18, p = 1.05 x 10-{superscript 2}). Furthermore, symptoms of mood disorder increased more steeply with increased caregiver-CYP hostility in CYP with ND-CNVs (interaction effect: {beta} = 0.15, p = 4.55 x 10-{superscript 2}). ConclusionsRaising a CYP with a rare genetic condition is challenging. Timely access to interventions that support caregivers in fostering a positive family environment may reduce behavioural difficulties in CYP, with subsequent benefits for family functioning.

BackgroundEarly adolescence is a common period of onset for depressive symptoms. In part, this may reflect a developmental manifestation of individuals genetic propensities as they undergo physiological and hormonal changes and interact with new environments. Many commonly proposed mechanisms assume direct effects of an individuals own genes on emerging variation in their depressive symptomatology. However, estimates of genetic influence based on analyses in unrelated individuals capture not only direct genetic effects but also genetic effects from parents and other biologically related family members. AimIn data from the Norwegian Mother, Father and Child Cohort (MoBa), we used linear mixed models to distinguish developmentally-stable and adolescence-specific direct and parental indirect genetic effects. We examined effects of polygenic scores for major depressive disorder (MDD), ADHD, anxiety disorders, and educational attainment (EA) on depressive symptoms, which were assessed by maternal reports at ages 8 and 14. ResultsChildrens own MDD polygenic scores showed adolescence-specific effects on depressive symptoms ({beta}PGS*wave=0.041, [95% CI: 0.017, 0.065]). Developmentally-stable direct effects from childrens polygenic scores for MDD ({beta}=0.016, [0.006, 0.039]), ADHD ({beta}=0.024, [0.008, 0.041]) and EA ({beta}=-0.02, [-0.038, -0.002]) were also evident. The only evidence of indirect genetic effects was a stable effect of maternal EA polygenic scores ({beta}=0.04, [0.024, 0.054]). ConclusionDirect genetic effects linked to genetic liability to MDD accounted for emerging variation in depressive symptoms in adolescence. These results imply that specific etiological mechanisms related to MDD may become particularly relevant for depressive symptoms during early adolescence compared to at earlier ages.

BackgroundMost studies seeking to identify youth at increased risk for depression have developed prediction models using a limited set of risk factors in general population samples. It is unclear whether these models generalize to high-risk youth. Here, we developed machine learning algorithms to predict first-onset depression in youth from the general population and high-risk youth with attention-deficit/hyperactivity disorder (ADHD). MethodsParticipants were 4803 unrelated children from the ABCD study with no prior mood disorder and complete data at baseline (age 9-10 years) and 2-year follow-up. Support Vector Machine, Random Forest, and Elastic Net models were used to predict first-onsets from clinically-relevant risk factors spanning mental and physical health, cognitive, dispositional, interpersonal, and socio-environmental domains. Predictive performance was evaluated in the full sample and separately in participants with ADHD (N=584, 12.16%). ResultsModels trained on the full sample achieved good discriminative predictive power (area under the curve [AUC]=0.70 and accuracy=0.70-0.82). Predictors that replicated across models included earlier pubertal development, higher behavioral inhibition and aggression, and more time spent passively watching media content. In the ADHD subsample, model performance declined (AUC=0.46-0.61) and predictors only partly overlapped with those identified in the full sample. ConclusionsModels effectively predicted depression in the general population but showed poor generalization to high-risk youth with ADHD, suggesting different risk factors in this group. These findings highlight that models trained in general population samples may not generalize to high-risk groups, pointing to the need for more tailored efforts to predict depression in youth at increased risk.

Background: This study examined the association between caregiving demands and depression symptoms among caregivers of individuals with Down syndrome during the COVID-19 pandemic. Method: We conducted an online survey of 200 caregivers of children and adults with Down syndrome, including demographic data, the Patient Health Questionnaire-8 (PHQ-8), and questions about lack of childcare and taking over instruction during the pandemic. A multiple linear regression analysis identified predictors of caregiver depression symptoms. Results: Household income (B = -3.45, p < .001) and having to take over instruction (B = 2.24, p < .001) were significant predictors of PHQ-8 scores. Child age, caregiver gender, difficulty paying for health insurance, and lack of childcare were not significant predictors. Conclusions: Lower income and instructional caregiving demands were associated with higher depression symptoms among caregivers of individuals with Down syndrome, suggesting potential targets for policy and intervention during future public health emergencies.

Mental health problems, including emotional problems, are linked to adverse educational outcomes among children and adolescents. This study examines the association between early onset of mental health problems generally, and emotional problems specifically, at ages 5-14, and outcomes from the General Certificate of Secondary Education (GCSE), a secondary education qualification, at age 16 for 4,783 students in England, using the Millennium Cohort Study dataset linked to the National Pupil Database. We found that the onset of mental health problems at ages 5, 7, 11 and 14 had a significant and negative association with all GCSE outcomes. We also found negative associations between early onset emotional problems and GCSE outcomes, although results were most stark for emotional problems that onset at age 11, with statistically significant negative associations with all GCSE outcomes. School absence was identified as a potential mediator of the negative association. Furthermore, this study found that the potential loss of productivity related to mental health problems in general and emotional problems in particular was over 23,000 sterling and 11,000 sterling per affected individual, respectively, which could translate into approximately 2.57 billion sterling and 1.6 billion sterling, respectively at the population level for England. These findings highlight the importance of early intervention for children and adolescents with mental health problems to improve educational and future outcomes.

AimAutistic children have a high but varied prevalence of internalizing and externalizing problems. This study aimed to identify the subtypes of internalizing and externalizing problems among autistic preschool children in Japan, examine their temporal stability, and investigate differences in participation in daily life and family outcomes across these subtypes. MethodsA prospective cohort study was conducted with 275 caregivers of autistic children aged 51-75 months. Internalizing and externalizing problems were assessed using the Strengths and Difficulties Questionnaire. ResultsLatent transition analysis identified five subtypes: Low-symptom, High-emotional, Externalizing, Comorbid, and Peer-difficulty groups. Membership in the High-emotional and Externalizing groups was relatively stable over time, whereas the Peer-difficulty group showed frequent transitions to subtypes with higher levels of internalizing or externalizing problems. Significant differences in participation in daily life and family outcomes were observed across subtypes, but these patterns were inconsistent with a simple gradient of symptom levels. ConclusionsThe novel findings that the temporal stability of subtype membership varied and that differences in participation in daily life and family outcomes were observed across the subtypes suggest that the heterogeneity of internalizing and externalizing problems may be associated with variations in childrens participation in daily life and family outcomes over time. Plain Language SummaryAutistic preschool children often experience emotional and behavioral difficulties, but the way these difficulties manifest varies widely across individuals. This study aimed to identify the patterns of these difficulties, examine how they change over time, and investigate how participation in daily life and family outcomes differ across autistic preschool children. We conducted a study with 275 caregivers of autistic children aged 4-6 years in Japan. From caregiver reports of childrens emotional and behavioral difficulties, five distinct patterns were identified: a group with mainly emotional difficulties, a group with mainly behavioral difficulties, a group with both types of difficulties, a group with relatively low levels of difficulties, and a group characterized primarily by peer-related difficulties. Our findings suggest that different patterns of emotional and behavioral difficulties are associated with differences in childrens participation in daily life and family outcomes. These differences could not be explained simply by the overall severity of difficulties but rather reflect distinct patterns based on the type of difficulty. The results indicate that autistic children face diverse difficulties that change over time.

Background: Sleep debt and irregular sleep patterns are highly prevalent amongst adolescents. However, whether the absence of these sleep behaviours protects against subsequent depression remains unclear. Here, we examined the association of sleep debt, weekend catch-up sleep (WCS), and social jetlag (SJL) in adolescence with depression in young adulthood and identified underlying biopsychosocial mechanisms. Methods: Secondary data analyses were conducted using the Avon Longitudinal Study of Parents and Children. Bedtimes and wake-up times on school days and weekends (i.e., sleep duration) and sleep need were self-reported at 15 years. This was used to generate sleep debt (sleep need minus school day sleep duration), WCS (weekend sleep duration minus school day sleep duration), and SJL (absolute difference in the midpoint of sleep times between school days and weekends). Depression was assessed at 24 years with the Clinical Interview Schedule-Revised. Common mental health symptoms, biological, and school-related factors at 17 years were the mediators. Results: Logistic regression analyses revealed that greater WCS (adjusted odds ratio [AOR]=0.90; 95% CI=0.84-0.97; p=0.004) and lower sleep debt (AOR=1.10; 95% confidence interval [CI]=1.03-1.18; p=0.005) at age 15 reduced the likelihood of depression at 24 years. Irritability at 17 years partially mediated the relationship between sleep debt and depression (bias-corrected estimate=0.003; 95% CI=0.002-0.004; p<0.001). Conclusions: Adolescents who experience less sleep debt (i.e., less discrepancies between their actual sleep and their perceived sleep need) and those who extend their sleep duration on weekends are at reduced risk for depression in young adulthood. These findings underscore the need for greater opportunities for adolescents to obtain more hours of sleep to protect them against later poor mental health outcomes, such as depression. Keywords: Sleep; longitudinal studies; depression; ALSPAC