Body mass index across development and adolescent hair cortisol: the role of persistence, variability, and timing of exposure.

BACKGROUND: Research suggests a putative role of the glucocorticoid stress hormone cortisol in the accumulation of adiposity. However, obesity and weight fluctuations may also wear and tear physiological systems promoting adaptation, affecting cortisol secretion. This possibility remains scarcely investigated in longitudinal research. This study tests whether trajectories of body mass index (BMI) across the first 15 years of life are associated with hair cortisol concentration (HCC) measured two years later and whether variability in BMI and timing matter. METHODS: BMI (kg/m2) was prospectively measured at twelve occasions between age 5 months and 15 years. Hair was sampled at age 17 in 565 participants. Sex, family socioeconomic status, and BMI measured concurrently to HCC were considered as control variables. RESULTS: Latent class analyses identified three BMI trajectories: "low-stable" (59.2%, n = 946), "moderate" (32.6%, n = 507), and "high-rising" (8.2%, n = 128). BMI variability was computed by dividing the standard deviation of an individual's BMI measurements by the mean of these measurements. Findings revealed linear effects, such that higher HCC was noted for participants with moderate BMI trajectories in comparison to low-stable youth (ß = 0.10, p = 0.03, 95% confidence interval (CI) = [0.02-0.40]); however, this association was not detected in the high-rising BMI youth (ß = -0.02, p = 0.71, 95% CI = [-0.47-0.32]). Higher BMI variability across development predicted higher cortisol (ß = 0.17, p = 0.003, 95% CI = [0.10-4.91]), additively to the contribution of BMI trajectories. BMI variability in childhood was responsible for that finding, possibly suggesting a timing effect. CONCLUSIONS: This study strengthens empirical support for BMI-HCC association and suggests that more attention should be devoted to BMI fluctuations in addition to persistent trajectories of BMI.

Adolescents and Social Media: Longitudinal Links Between Motivations for Using Social Media and Subsequent Internalizing Symptoms.

Knowledge is lacking on whether adolescents' motivations for social media use predict internalizing symptoms, and few studies have considered the moderating role of extraversion. In 2017 (T1) and 2018 (T2), 197 adolescents (49.70% girls, Mage = 13.15, SD = 0.36) from a large metropolitan area participated in this study. Adolescents reported on their social media use motivations and extraversion (at T1) and depressive and anxiety symptoms (T1 and T2). Latent class analysis revealed four motivation profiles at T1: (1) entertainment and fun (30.97%); (2) avoidance and escapism (14.21%); (3) meeting new people, feel involved (16.75%); (4) boredom (38.07%). Social motivations (profile 3) predicted elevated internalizing symptoms at T2. Avoidance and boredom motivations (profile 2 and 4) predicted internalizing symptoms for adolescents with low extraversion. Social media use motivations and extraversion distinguish adolescents who benefit from social media from those who experience difficulties.

The interplay of maternal and paternal postpartum depressive symptoms with children's internalizing and externalizing symptoms from childhood to adolescence: does socioeconomic status matter? A longitudinal cohort study.

BACKGROUND: Maternal postpartum depression is an important risk factor for internalizing and externalizing problems in children. The role of concurrent paternal depression remains unclear, especially by socioeconomic status. This study examined independent and interactive associations of postpartum maternal and paternal depression with children's internalizing/externalizing symptoms throughout childhood and adolescence (ages 3.5-17 years). METHODS: We used data from the Québec Longitudinal Study of Child Development, a representative birth cohort (1997-1998) in Canada. Data included self-reported maternal and paternal depressive symptoms at 5 months' postpartum using the Center for Epidemiologic Studies Depression Scale. Internalizing and externalizing symptoms in children were reported by parents, teachers and children/adolescents using the Social Behaviour Questionnaire (ages 3.5-13 years) and the Mental Health and Social Inadaptation Assessment for Adolescents (ages 15-17 years). We used three-level mixed effects modelling to test associations after adjusting for confounding factors. RESULTS: With 168 single-parent families excluded, our sample consisted of 1,700 families with useable data. Of these, 275 (16.2%) families reported maternal depression (clinically elevated symptoms), 135 (7.9%) paternal depression and 39 (2.3%) both. In families with high socioeconomic status, maternal depression was associated with greater child internalizing (ß = .34; p < .001) and externalizing symptoms (ß = .22; p = .002), regardless of the presence/absence of paternal depression. In families with low socioeconomic status, associations with symptoms were stronger with concurrent paternal depression (internalizing, ß = .84, p < .001; externalizing, ß = .71, p = .003) than without (internalizing, ß = .30, p < .001; externalizing, ß = .24, p = .002). CONCLUSIONS: Maternal depression increases the risk for children's internalizing/externalizing problems in all socioeconomic contexts. In families with low socioeconomic status, risks were exacerbated by concurrent paternal depression. Postpartum depression, especially in low socioeconomic environments, should be a primary focus to optimize mental health across generations.

Differential Association of Preadolescent Risk Factors Across Developmental Patterns of Adolescent Concurrent Gambling Participation and Substance Use.

Early risk factors for gambling participation (GP) and substance use (SU) in adolescents have usually been studied separately, although these disorders were integrated into the same clinical category over a decade ago. This exploratory study aimed to investigate the early individual, parental, familial and social risk factors associated with developmental patterns of adolescent GP and SU in a population-representative cohort (N = 1594, 51.2% boys). Using a person-centered strategy and multiple assessments from age 12 to 17, six developmental patterns describing joint GP and SU courses were revealed. Non-substance users/non-gamblers served as the reference class in an integrated longitudinal-multivariate analysis framework examining 15 distinct risk factors. Results showed that a core of risk factors were common to all trajectory-classes of substance users with or without GP. For a similar level of SU, most of the risk factors associated with non-gambling users also affected their gambling peers. However, additional risk factors were specifically related to GP. Thus, substance users who also gamble were affected by a greater number of risk factors than non-gambling substance users. Findings are consistent with a developmental syndrome of addiction, which posits a shared etiology between different expressions of addiction as well as differences in risk factors that lead to distinct trajectories of addictive behaviors. They highlight the importance of considering both GP and SU for a comprehensive assessment of adolescents' level of risk with regard to addictive behaviors.

Developmental Losses of Preschool Children Three Years into the COVID-19 Pandemic.

The COVID-19 pandemic and resulting mitigation measures have led to increased vulnerabilities in early child development. However, research is scarce and there are no studies on the persistence of these losses three years into the pandemic among young children. To fill in this gap, we examined census-like evaluations of school readiness carried out among preschoolers in Uruguay. The assessments were carried out among 5 cohorts of 5-year-olds: who were assessed prior to the pandemic (2018, 2019); during the pandemic (2020, 2021); and after the health emergency declaration ended in Uruguay (2022). A total of 180,984 teacher evaluations were included covering cognitive, motor and socio-emotional development, as well as attitudes toward learning. Overall, we found that scores in most spheres of child development decreased from before to during the pandemic in 2020 and 2021. In 2022, scores returned to pre-pandemic levels. Our findings suggest the recovery of developmental losses among cohorts of children in kindergarten took more than two years in a country that experienced a mild-to-moderate impact of the COVID-19 pandemic.

Childhood and Adolescent Depression Symptoms and Young Adult Mental Health and Psychosocial Outcomes.

Importance: Depression is a leading cause of disability. The timing and persistence of depression may be differentially associated with long-term mental health and psychosocial outcomes. Objective: To examine if depression symptoms during early and middle childhood and adolescence and persistent depression symptoms are associated with impaired young adult outcomes independent of early risk factors. Design, Setting, and Participants: Data for this prospective, longitudinal cohort study were from the Québec Longitudinal Study of Child Development, a representative population-based Canadian birth cohort. The cohort consists of infants born from October 1, 1997, to July 31, 1998. This is an ongoing study; data are collected annually or every 2 years and include those ages 5 months to 21 years. The end date for the data in this study was June 30, 2019, and data analyses were performed from October 4, 2022, to January 3, 2024. Exposures: Depression symptoms were assessed using maternal reports in early childhood (ages 1.5 to 6 years) from 1999 to 2004, teacher reports in middle childhood (ages 7 to 12 years) from 2005 to 2010, and self-reports in adolescence (ages 13 to 17 years) from 2011 to 2015. Main Outcomes and Measures: The primary outcome was depression symptoms at age 20 years, and secondary outcomes were indicators of psychosocial functioning (binge drinking; perceived stress; not being in education, employment, or training; social support; and experiencing online harrasment) at age 21 years. All outcomes were self-reported. Adult outcomes were reported by participants at ages 20 and 21 years from 2017 to 2019. Risk factors assessed when children were aged 5 months old were considered as covariates to assess the independent associations of childhood and adolescent depression symptoms with adult outcomes. Results: The cohort consisted of 2120 infants. The analytic sample size varied from 1118 to 1254 participants across outcomes (56.85% to 57.96% female). Concerning the primary outcome, adjusting for early risk factors and multiple testing, depression symptoms during adolescence were associated with higher levels of depression symptoms (ß, 1.08 [95% CI, 0.84-1.32]; P < .001 unadjusted and Bonferroni adjusted) in young adulthood. Concerning the secondary outcomes, depression symptoms in adolescence were only associated with perceived stress (ß, 3.63 [95% CI, 2.66-4.60]; P < .001 unadjusted and Bonferroni adjusted), while both middle-childhood (ß, -1.58 [95% CI, -2.65 to -0.51]; P = .003 unadjusted and P < .001 Bonferroni adjusted) and adolescent (ß, -1.97 [95% CI, -2.53 to -1.41]; P < .001 unadjusted and Bonferroni adjusted) depression symptoms were associated with lower levels of social support. There were no associations for binge drinking; not being in education, employment, or training; or experiencing online harrasment. Conclusions and Relevance: In this cohort study of Canadian children and adolescents, childhood and adolescent depression symptoms were associated with impaired adult psychosocial functioning. Interventions should aim to screen and monitor children and adolescents for depression to inform policymaking regarding young adult mental health and psychosocial outcomes.

Pandemic Stringency Measures and Hospital Admissions for Eating Disorders.

Importance: Hospitalizations for eating disorders rose dramatically during the COVID-19 pandemic. Public health restrictions, or stringency, are believed to have played a role in exacerbating eating disorders. Few studies of eating disorders during the pandemic have extended to the period when public health stringency restrictions were lifted. Objective: To assess the association between hospitalization rates for eating disorders and public health stringency during the COVID-19 pandemic and after the easing of public health restrictions. Design, Setting, and Participants: This Canadian population-based cross-sectional study was performed from April 1, 2016, to March 31, 2023, and was divided into pre-COVID-19 and COVID-19-prevalent periods. Data were provided by the Canadian Institute for Health Information and the Institut National d'Excellence en Santé et Services Sociaux for all Canadian provinces and territories. Participants included all children and adolescents aged 6 to 20 years. Exposure: The exposure was public health stringency, as measured by the Bank of Canada stringency index. Main Outcomes and Measures: The primary outcome was hospitalizations for a primary diagnosis of eating disorders (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision code F50), stratified by region, age group, and sex. Interrupted time series analyses based on Poisson regression were used to estimate the association between the stringency index and the rate of hospitalizations for eating disorders. Results: During the study period, there were 11 289 hospitalizations for eating disorders across Canada, of which 8726 hospitalizations (77%) were for females aged 12 to 17 years. Due to low case counts in other age-sex strata, the time series analysis was limited to females within the 12- to 17-year age range. Among females aged 12 to 17 years, a 10% increase in stringency was associated with a significant increase in hospitalization rates in Quebec (adjusted rate ratio [ARR], 1.05; 95% CI, 1.01-1.07), Ontario (ARR, 1.05; 95% CI, 1.03-1.07), the Prairies (ARR, 1.08; 95% CI, 1.03-1.13), and British Columbia (ARR, 1.11; 95% CI, 1.05-1.16). The excess COVID-19-prevalent period hospitalizations were highest at the 1-year mark, with increases in all regions: Quebec (RR, 2.17), Ontario (RR, 2.44), the Prairies (RR, 2.39), and British Columbia (RR, 2.02). Conclusion and Relevance: In this cross-sectional study of hospitalizations for eating disorders across Canada, hospitalization rates for eating disorders in females aged 12 to 17 years were associated with public health measure stringency. The findings suggest that future pandemic preparedness should consider implications for youths at risk for eating disorders and their resource and support needs.

Mental Health Hospitalizations in Canadian Children, Adolescents, and Young Adults Over the COVID-19 Pandemic.

Importance: The COVID-19 pandemic resulted in multiple socially restrictive public health measures and reported negative mental health impacts in youths. Few studies have evaluated incidence rates by sex, region, and social determinants across an entire population. Objective: To estimate the incidence of hospitalizations for mental health conditions, stratified by sex, region, and social determinants, in children and adolescents (hereinafter referred to as youths) and young adults comparing the prepandemic and pandemic-prevalent periods. Design, Setting, and Participants: This Canadian population-based repeated ecological cross-sectional study used health administrative data, extending from April 1, 2016, to March 31, 2023. All youths and young adults from 6 to 20 years of age in each of the Canadian provinces and territories were included. Data were provided by the Canadian Institute for Health Information for all provinces except Quebec; the Institut National d'Excellence en Santé et en Services Sociaux provided aggregate data for Quebec. Exposures: The COVID-19-prevalent period, defined as April 1, 2020, to March 31, 2023. Main Outcomes and Measures: The main outcome measures were the prepandemic and COVID-19-prevalent incidence rates of hospitalizations for anxiety, mood disorders, eating disorders, schizophrenia or psychosis, personality disorders, substance-related disorders, and self-harm. Secondary measures included hospitalization differences by sex, age group, and deprivation as well as emergency department visits for the same mental health conditions. Results: Among Canadian youths and young adults during the study period, there were 218 101 hospitalizations for mental health conditions (ages 6 to 11 years: 5.8%, 12 to 17 years: 66.9%, and 18 to 20 years: 27.3%; 66.0% female). The rate of mental health hospitalizations decreased from 51.6 to 47.9 per 10 000 person-years between the prepandemic and COVID-19-prevalent years. However, the pandemic was associated with a rise in hospitalizations for anxiety (incidence rate ratio [IRR], 1.11; 95% CI, 1.08-1.14), personality disorders (IRR, 1.21; 95% CI, 1.16-1.25), suicide and self-harm (IRR, 1.10; 95% CI, 1.07-1.13), and eating disorders (IRR, 1.66; 95% CI, 1.60-1.73) in females and for eating disorders (IRR, 1.47; 95% CI, 1.31-1.67) in males. In both sexes, there was a decrease in hospitalizations for mood disorders (IRR, 0.84; 95% CI, 0.83-0.86), substance-related disorders (IRR, 0.83; 95% CI, 0.81-0.86), and other mental health disorders (IRR, 0.78; 95% CI, 0.76-0.79). Conclusions and Relevance: This cross-sectional study of Canadian youths and young adults found a rise in anxiety, personality disorders, and suicidality in females and a rise in eating disorders in both sexes in the COVID-19-prevalent period. These results suggest that in future pandemics, policymakers should support youths and young adults who are particularly vulnerable to deterioration in mental health conditions during public health restrictions, including eating disorders, anxiety, and suicidality.

On executive functioning and childcare: The moderating role of parent-child interactions.

Childcare services are widely used by families and thereby exert an important influence on many young children. Yet, little research has examined whether childcare may impact the development of child executive functioning (EF), one of the pillars of cognitive development in early childhood. Furthermore, despite persisting hypotheses that childcare may be particularly beneficial for children who have less access to optimal developmental resources at home, research has yet to address the possibility that putative associations between childcare and EF may vary as a function of family factors. Among a sample of 180 mostly White middle-class families (91 girls), we examined if childcare participation in infancy was related to two aspects of EF (Delay and Conflict) at 3 years, and whether two aspects of maternal parenting behavior (sensitivity and autonomy support) moderated these associations. The results showed positive associations between participation in group-based childcare and Delay EF specifically among children of relatively less autonomy-supportive mothers. These findings suggest that out-of-home childcare services may play a protective role for children exposed to parenting that is less conducive to their executive development. RESEARCH HIGHLIGHTS: Little research has considered effects of childcare in infancy on executive functioning (EF). Long-standing hypothesis that childcare is more beneficial for children exposed to less sensitive and supportive parenting. We test interactions between maternal parenting and childcare participation in infancy in relation to EF at age 3 years. We find positive associations between participation in group-based childcare and Delay EF specifically among children of relatively less autonomy-supportive mothers.

Hair steroid before and after COVID-19 in preschoolers: the moderation of family characteristics.

BACKGROUND: Frequent or prolonged exposure to stressors may jeopardize young children's health. The onset of the COVID-19 pandemic, coupled with disruptions in daily routines and social isolation resulting from public health preventive measures, have raised concerns about its potential impact on children' experienced stress, particularly for young children and vulnerable families. However, whether the pandemic was accompanied by changes in physiological stress remains unknown as perceived stress is not a good proxy of physiological stress. This study examined if preschoolers showed increasing hair steroid concentrations following the onset of the COVID-19 pandemic and whether family characteristics may have exacerbated or buffered these changes. METHODS: 136 preschoolers (2-4 years) provided hair for steroid measurement (cortisol, dehydroepiandrosterone (DHEA), cortisone, cortisol-to-DHEA ratio, cortisol-to-cortisone ratio) in October-November 2019 (T0) and in July-August 2020 (T1). A 2-centimeter hair segment was analyzed, reflecting steroid production over the two months leading up to collection. Family income, conflict resolution and lack of cohesion, as well as parents' COVID-19 stress were reported by parents. Linear mixed models for repeated measures and Bayes factors were used. RESULTS: No significant changes were noted from before to after the onset of the COVID-19 pandemic for most hair steroids. However, a moderating role of family conflict resolution was noted. Children living with parents with a better ability to resolve conflicts had lower levels of DHEA compared to those who had more difficulty managing conflicts. Additionally, lower levels of family cohesion and income were linked to some steroids, especially DHEA, suggesting that these factors may relate to children's physiological stress. Finally, boys had higher DHEA levels than girls. CONCLUSION: Our findings suggest that stress biomarkers were comparable from before to during the COVID-19 pandemic. This observation holds true despite the pandemic being perceived by many as a novel, unpredictable, and potentially threatening event. Findings further suggest that family characteristics are associated with hair steroid, especially DHEA, which deserves further investigation.

Revisiting the childcare-attachment question: under what conditions is childcare participation associated with mother-child attachment security?

Decades have passed since the controversy regarding the putative risks of childcare for mother-child attachment broke out. Yet, some uncertainty remains, as relevant studies have produced inconsistent evidence. Some have proposed that those conflicting findings may be due to the fact that the effects of childcare are conditioned on parenting. Accordingly, this study examined whether relations between childcare participation and mother-child attachment vary according to maternal sensitivity and autonomy support. In this sample of 236 mother-child dyads, there was no indication of main effects of childcare participation on attachment. There were, however, some interactive effects, such that the children who showed the least secure attachment behaviors were those who did not attend childcare and had either less sensitive or less autonomy-supportive mothers. The findings suggest that the effects of childcare on mother-child attachment are best understood in light of the parenting children receive at home.

Childhood behavior problems and adverse economic outcomes: a 30-year population-based study of intergenerational income mobility.

BACKGROUND: The objectives of this study were to (a) assess the associations between early behavioral problems and intergenerational income mobility (i.e., the degree to which income status is transmitted from one generation to the next), (b) verify whether these associations are moderated by child sex, and (c) explore indirect effects of early behavioral problems on income mobility via high school graduation. METHODS: Data were drawn from the Quebec Longitudinal Study of Kindergarten Children (n = 3,020; 49.17% girls). Participants were followed from age 6 to 37 years. Measures included parents' and teachers' ratings of behavioral problems at age 6 years as well as participants' (ages 30-35 years) and their parents' (when participants were aged 10-19 years) income data obtained from tax return records. Regression models were used to predict upward and downward mobility (i.e., increased or decreased income status from one generation to the next) from attention-deficit/hyperactivity problems, conduct/opposition problems, depression/anxiety problems, prosociality, and the quality of children's relationship with their caregiver. Two-way interaction effects between behavioral problems and child sex were examined and indirect effect models including high school graduation as a mediator of these associations were conducted. RESULTS: Despite their higher educational attainment, females had lower incomes and experienced lower upward (but higher downward) income mobility than males. For both females and males, higher levels of attention-deficit/hyperactivity and conduct/opposition problems were associated with decreased odds of upward mobility, whereas higher levels of attention-deficit/hyperactivity were associated with increased odds of downward mobility. Attention-deficit/hyperactivity problems, conduct/opposition problems as well as low prosociality were associated with lower educational attainment (no high school diploma), which in turn was associated with increased odds of downward mobility. CONCLUSIONS: Results highlight the importance of providing intensive support to children with early behavioral problems as a means of improving educational attainment and intergenerational income mobility.

Cord serum cytokines at birth and children's trajectories of mood dysregulation symptoms from 3 to 8 years: The EDEN birth cohort.

There is growing evidence that in utero imbalance immune activity plays a role in the development of neurodevelopmental and psychiatric disorders in children. Mood dysregulation (MD) is a debilitating transnosographic syndrome whose underlying pathophysiological mechanisms could be revealed by studying its biomarkers using the Research Domain Criteria (RDoC) model. Our aim was to study the association between the network of cord serum cytokines, and mood dysregulation trajectories in offsprings between 3 and 8 years of age. We used the data of a study nested in the French birth cohort EDEN that took place from 2003 to 2014 and followed mother-child dyads from the second trimester of pregnancy until the children were 8 years of age. The 2002 mother-child dyads were recruited from the general population through their pregnancy follow-up in two French university hospitals. 871 of them were included in the nested cohort and cord serum cytokine levels were measured at birth. Children's mood dysregulation symptoms were assessed with the Strengths and Difficulties Questionnaire Dysregulation Profile at the ages 3, 5 and 8 years in order to model their mood dysregulation trajectories. Out of the 871 participating dyads, 53% of the children were male. 2.1% of the children presented a high mood dysregulation trajectory whereas the others were considered as physiological variations. We found a significant negative association between TNF-α cord serum levels and a high mood dysregulation trajectory when considering confounding factors such as maternal depression during pregnancy (adjusted Odds Ratio (aOR) = 0.35, 95% Confidence Interval (CI) [0.18-0.67]). Immune imbalance at birth could play a role in the onset of mood dysregulation symptoms. Our findings throw new light on putative immune mechanisms implicated in the development of mood dysregulation and should lead to future animal and epidemiological studies.

Longitudinal study of childhood sleep trajectories and adolescent mental health problems.

Study Objective: To investigate whether childhood sleep trajectories are associated with mental health symptoms such as social phobia, generalized anxiety, depression, attention deficit hyperactivity disorder (ADHD), conduct problems, and opposition at age 15. Methods: A total of 2120 children took part in the Quebec Longitudinal Study of Child Development. Childhood sleep trajectories were computed from maternal reports at 2.5, 3.5, 4, 6, 8, 10, and/or 12 years. At age 15, 1446 adolescents filled out mental health and sleep questions. A path analysis model was assessed in the full sample. Results: Four childhood nocturnal sleep duration trajectories were identified: (1) a short pattern (7.5%), (2) a short-increasing pattern (5.8%), (3) a 10 hours pattern (50.7%), and (4) an 11 hours pattern (36.0%). Three childhood sleep latency trajectories were found: (1) a short pattern (31.7%), (2) an intermediate pattern (59.9%), and (3) a long pattern (8.4%). Finally, two childhood wakefulness after sleep-onset trajectories were found: (1) a normative pattern (73.0%) and (2) a long pattern (27.0%). The path analysis model indicated that children following a long childhood sleep latency trajectory were more likely to experience symptoms of depression (ß = 0.06, 95% CI: 0.01 to 0.12), ADHD (ß = 0.07, 95% CI: 0.02 to 0.13), conduct problems (ß = 0.05, 95% CI: 0.00 to 0.10) and opposition (ß = 0.08, 95% CI: 0.02 to 0.13) at age 15. Conclusions: This longitudinal study revealed that children presenting a long sleep latency throughout childhood are at greater risk of symptoms of depression, ADHD, conduct problems, and opposition in adolescence.

Mental health of Canadian youth: A systematic review and meta-analysis of studies examining changes in depression, anxiety, and suicide-related outcomes during the COVID-19 pandemic.

OBJECTIVES: This systematic review and meta-analysis aims to describe Canadian youth mental health during the COVID-19 pandemic, focusing on changes in anxiety and depressive symptoms and suicidality. METHODS: We searched four databases up to February 2023 for longitudinal or repeated cross-sectional studies reporting on changes in depressive and anxiety symptoms, suicidality, or related services utilization among young people under 25 years old residing in Canada during the COVID-19 pandemic. Random-effects meta-analyses were performed for studies comparing depressive and anxiety symptoms from before to during the first, second, and third COVID-19 waves (up to June 2021), and between COVID-19 waves. Other studies were described narratively. Risk of bias was assessed using an adapted Joanna Briggs Institute Checklist. SYNTHESIS: Of the 7916 records screened, 35 articles met inclusion criteria for this review. Included studies were highly heterogeneous in design, population, and type of change investigated, and many had a high risk of bias. The meta-analyses found that depressive symptoms worsened minimally from pre-pandemic to wave 1 but returned to pre-pandemic levels by wave 2. Anxiety symptoms were broadly comparable from pre-pandemic to waves 1 and 2 but worsened from waves 1 to 3 and from pre-pandemic to wave 1 for girls. The narrative review included several studies that provided inconclusive evidence of increases in services utilization. CONCLUSION: The current evidence is limited and highly heterogeneous, making it insufficient to draw definitive conclusions regarding the short- to medium-term impact of the pandemic on youth mental health in Canada. Obtaining better mental health surveillance among Canadian youth is imperative.

RéSUMé: OBJECTIFS: Cette revue systématique et méta-analyse vise à décrire la santé mentale des jeunes Canadiens pendant la pandémie de COVID-19 en ce qui concerne les changements dans les symptômes d'anxiété et de dépression et la suicidalité. MéTHODES: Nous avons cherché dans quatre bases de données, jusqu'en février 2023, des études longitudinales ou transversales répétées portant sur l'évolution des symptômes dépressifs et anxieux, de la suicidalité ou de l'utilisation des services en santé mentale chez les jeunes de moins de 25 ans résidant au Canada pendant la pandémie de COVID-19. Des méta-analyses à effets aléatoires ont été réalisées pour les études comparant les symptômes dépressifs et anxieux avant et pendant les première, deuxième et troisième vagues du COVID-19 (jusqu'en juin 2021), ainsi qu'entre les vagues de COVID-19. Les autres études ont été décrites de manière narrative. Le risque de biais a été évalué à l'aide d'une liste de contrôle adaptée du Joanna Briggs Institute. SYNTHèSE: Sur les 7 916 dossiers examinés, 35 articles répondaient aux critères d'inclusion de la présente étude. Les études retenues sont très hétérogènes en termes de conception, de population et de type de changement étudié, et un grand nombre d'entre elles présentent un risque élevé de biais. Les méta-analyses révèlent que les symptômes dépressifs se sont légèrement aggravés entre la période prépandémique et la première vague, mais qu'ils sont revenus aux niveaux prépandémiques lors de la deuxième vague. Les symptômes d'anxiété sont globalement comparables entre la période prépandémique et les vagues 1 et 2, mais se sont aggravés entre les vagues 1 et 3 et entre la période prépandémique et la vague 1 pour les filles. La revue narrative porte sur plusieurs études qui ont fourni des preuves non concluantes de l'augmentation de l'utilisation des services en santé mentale. CONCLUSION: Les données actuelles sont limitées et très hétérogènes, ce qui ne permet pas de tirer des conclusions définitives quant à l'impact à court et moyen terme de la pandémie sur la santé mentale des jeunes au Canada. Il est impératif d'améliorer la surveillance de la santé mentale des jeunes Canadiens.

Association of childhood externalizing, internalizing, comorbid problems with criminal convictions by early adulthood.

Childhood externalizing problems have been linked with adult criminality. However, little is known about criminal outcomes among children with comorbid externalizing and internalizing problems. We examined the associations between profiles of behavioral problems during childhood (i.e., externalizing, internalizing, and comorbid) and criminality by early adulthood. Participants were N = 3017 children from the population-based Quebec Longitudinal Study of Kindergarten Children followed up from age 6-25. Multitrajectory modeling of teacher-rated externalizing and internalizing problems from age 6-12 years identified four distinct profiles: no/low, externalizing, internalizing, and comorbid problems. Juvenile (age 13-17) and adult (age 18-25) criminal convictions were extracted from official records. Compared to children in the no/low profile, those in the externalizing and comorbid profiles were at higher risk of having a criminal conviction, while no association was found for children in the internalizing profile. Children with comorbid externalizing and internalizing problems were most at risk of having a criminal conviction by adulthood, with a significantly higher risk when compared to children with externalizing or internalizing problems only. Similar results were found when violent and non-violent crimes were investigated separately. Specific interventions targeting early comorbid behavioral problems could reduce long-term criminality.

The intergenerational continuity of alcohol use in a population sample.

INTRODUCTION: Research shows that parental alcohol use predicts youths' alcohol use, but this intergenerational continuity may vary across countries, and little is known about its moderators. This study examined for the first time the intergenerational continuity in alcohol use in a population sample of families in Canada, and tested whether it varied by youths' sex, family income, or family structure. METHODS: We used prospective longitudinal data on 1632 families from the Quebec Longitudinal Study of Child Development (QLSCD), a representative sample from the province of Quebec, Canada. Youths self-reported alcohol use and binge drinking frequency at seven timepoints from early adolescence to early adulthood. Predictors were mothers' and fathers' self-reported alcohol use from youths' infancy through age 13, and mother-reported socioeconomic variables. RESULTS: We identified three trajectories of alcohol use from ages 13 to 21 years: normative, late-onset and early-onset. Maternal alcohol use increased the youths' risk of following the early-onset trajectory of alcohol use, while both parents' alcohol use decreased the odds of the youths following the late-onset trajectory, compared to the normative trajectory. Insufficient family income increased youths' risk of following either the early-onset or late-onset trajectories. Mothers' and fathers' alcohol use did not interact in predicting youths' trajectory, and we found no moderating effects of the youths' sex, insufficient income, or years as a single-parent family. CONCLUSION: The results suggest modest intergenerational continuity of alcohol use in Quebec families which may be used, with income insufficiency, to help identify at-risk children for targeted interventions.

Does early child negative emotionality moderate the association between maternal stimulation and academic readiness and achievement?

We investigated whether child temperament (negative emotionality, 5 months) moderated the association between maternal stimulation (5 months-2½ years) and academic readiness and achievement (vocabulary, mathematics, and reading). We applied structural equation modeling to the data from the Quebec Longitudinal Study of Child Development (N = 1121-1448; mostly Whites; 47% girls). Compared to children with low negative emotionality, those with high negative emotionality had higher levels of academic readiness (6 years) and mathematics achievement (7 years) when exposed to high levels of maternal stimulation (ß = 3.17, p < .01 and ß = 2.91, p < .01, respectively). The results support the differential susceptibility model whereby highly emotionally negative children were more susceptible to the influences of low and high levels of maternal stimulation in academic readiness and mathematics achievement's developments.

Mechanisms and pathways linking kindergarten behavior problems with mid-life employment earnings for males from low-income neighborhoods.

Childhood behavior problems are associated with reduced labor market participation and lower earnings in adulthood, but little is known about the pathways and mechanisms that explain these associations. Drawing on a 33-year prospective birth cohort of White males from low-income backgrounds (n = 1040), we conducted a path analysis linking participants' teacher-rated behavior problems at age 6 years-that is, inattention, hyperactivity, aggression-opposition, and low prosociality-to employment earnings at age 35-39 years obtained from tax records. We examined three psychosocial mediators at age 11-12 years (academic, behavioral, social) and two mediators at age 25 years (non-high school graduation, criminal convictions). Our findings support the notion that multiple psychosocial pathways-especially low education attainment-link kindergarten behavior problems to lower employment earnings decades later.

Childhood behavioral problems are associated with the intergenerational transmission of low education: a 16-year population-based study.

The intergenerational transmission of low educational attainment is well-documented, but little is known about how behavioral problems in childhood explain this association. Drawing upon a population-based cohort study (n = 3020) linked to administrative records, we investigated the extent to which inattentive, internalizing, externalizing, and prosocial behaviors at child ages 6-8 years accounted for associations between parental education and child's risk of failing to graduate from high school. We adjusted for economic, demographic, cognitive, and perinatal factors, as well as parental mental health. Using logistic regressions and the Karlson-Holm-Breen decomposition method, we found that childhood behaviors together explained 19.5% of the association between mother's education and child's high school graduation status at age 22/23, and 13.7% of the association between father's education and this same outcome. Inattentive behaviors were most strongly associated with failure to graduate from high school, while the role of other behaviors was modest or negligible. Inattentive behaviors may represent a mediational pathway between parental education and child education. Early interventions targeting inattentive behaviors could potentially enhance the prospects of intergenerational educational mobility.