The trajectory of depression and anxiety among children and adolescents over two years of the COVID-19 pandemic.

Longitudinal research examining children's mental health (MH) over the course of the COVID-19 pandemic is scarce. We examined trajectories of depression and anxiety over two pandemic years among children with and without MH disorders. Parents and children 2-18 years completed surveys at seven timepoints (April 2020 to June 2022). Parents completed validated measures of depression and anxiety for children 8-18 years, and validated measures of emotional/behavioural symptoms for children 2-7 years old; children ≥10 years completed validated measures of depression and anxiety. Latent growth curve analysis determined depression and anxiety trajectories, accounting for demographics, child and parent MH. Data were available on 1315 unique children (1259 parent-reports; 550 child-reports). Trajectories were stable across the study period, however individual variation in trajectories was statistically significant. Of included covariates, only initial symptom level predicted symptom trajectories. Among participants with pre-COVID data, a significant increase in depression symptoms relative to pre-pandemic levels was observed; children and adolescents experienced elevated and sustained levels of depression and anxiety during the two-year period. Findings have direct policy implications in the prioritization and of maintenance of educational, recreational, and social activities with added MH supports in the face of future events.

Genome-wide association study identifies 30 obsessive-compulsive disorder associated loci.

Obsessive-compulsive disorder (OCD) affects ~1% of the population and exhibits a high SNP-heritability, yet previous genome-wide association studies (GWAS) have provided limited information on the genetic etiology and underlying biological mechanisms of the disorder. We conducted a GWAS meta-analysis combining 53,660 OCD cases and 2,044,417 controls from 28 European-ancestry cohorts revealing 30 independent genome-wide significant SNPs and a SNP-based heritability of 6.7%. Separate GWAS for clinical, biobank, comorbid, and self-report sub-groups found no evidence of sample ascertainment impacting our results. Functional and positional QTL gene-based approaches identified 249 significant candidate risk genes for OCD, of which 25 were identified as putatively causal, highlighting WDR6, DALRD3, CTNND1 and genes in the MHC region. Tissue and single-cell enrichment analyses highlighted hippocampal and cortical excitatory neurons, along with D1- and D2-type dopamine receptor-containing medium spiny neurons, as playing a role in OCD risk. OCD displayed significant genetic correlations with 65 out of 112 examined phenotypes. Notably, it showed positive genetic correlations with all included psychiatric phenotypes, in particular anxiety, depression, anorexia nervosa, and Tourette syndrome, and negative correlations with a subset of the included autoimmune disorders, educational attainment, and body mass index.. This study marks a significant step toward unraveling its genetic landscape and advances understanding of OCD genetics, providing a foundation for future interventions to address this debilitating disorder.

Genome-Wide Association Study of Obsessive-Compulsive Symptoms including 33,943 individuals from the general population.

While 1-2% of individuals meet the criteria for a clinical diagnosis of obsessive-compulsive disorder (OCD), many more (~13-38%) experience subclinical obsessive-compulsive symptoms (OCS) during their life. To characterize the genetic underpinnings of OCS and its genetic relationship to OCD, we conducted the largest genome-wide association study (GWAS) meta-analysis of parent- or self-reported OCS to date (N = 33,943 with complete phenotypic and genome-wide data), combining the results from seven large-scale population-based cohorts from Sweden, the Netherlands, England, and Canada (including six twin cohorts and one cohort of unrelated individuals). We found no genome-wide significant associations at the single-nucleotide polymorphism (SNP) or gene-level, but a polygenic risk score (PRS) based on the OCD GWAS previously published by the Psychiatric Genetics Consortium (PGC-OCD) was significantly associated with OCS (Pfixed = 3.06 × 10-5). Also, one curated gene set (Mootha Gluconeogenesis) reached Bonferroni-corrected significance (Ngenes = 28, Beta = 0.79, SE = 0.16, Pbon = 0.008). Expression of genes in this set is high at sites of insulin mediated glucose disposal. Dysregulated insulin signaling in the etiology of OCS has been suggested by a previous study describing a genetic overlap of OCS with insulin signaling-related traits in children and adolescents. We report a SNP heritability of 4.1% (P = 0.0044) in the meta-analyzed GWAS, and heritability estimates based on the twin cohorts of 33-43%. Genetic correlation analysis showed that OCS were most strongly associated with OCD (rG = 0.72, p = 0.0007) among all tested psychiatric disorders (N = 11). Of all 97 tested phenotypes, 24 showed a significant genetic correlation with OCS, and 66 traits showed concordant directions of effect with OCS and OCD. OCS have a significant polygenic contribution and share genetic risk with diagnosed OCD, supporting the hypothesis that OCD represents the extreme end of widely distributed OCS in the population.

Racial/Ethnic Disparities in Psychiatric Traits and Diagnoses within a Community-based Sample of Children and Youth: Disparités raciales/ethniques dans les traits et diagnostics psychiatriques au sein d'un échantillon communautaire d'enfants et de jeunes.

OBJECTIVE: Racial/ethnic disparities in the prevalence of psychiatric disorders have been reported, but have not accounted for the prevalence of the traits that underlie these disorders. Examining rates of diagnoses in relation to traits may yield a clearer understanding of the degree to which racial/ethnic minority youth in Canada differ in their access to care. We sought to examine differences in self/parent-reported rates of diagnoses for obsessive-compulsive disorder (OCD), attention-deficit/hyperactivity disorder (ADHD) and anxiety disorders after adjusting for differences in trait levels between youth from three racial/ethnic groups: White, South Asian and East Asian. METHOD: We collected parent or self-reported ratings of OCD, ADHD and anxiety traits and diagnoses for 6- to 17-year-olds from a Canadian general population sample (Spit for Science). We examined racial/ethnic differences in trait levels and the odds of reporting a diagnosis using mixed-effects linear models and logistic regression models. RESULTS: East Asian (N = 1301) and South Asian (N = 730) youth reported significantly higher levels of OCD and anxiety traits than White youth (N = 6896). East Asian and South Asian youth had significantly lower odds of reporting a diagnosis for OCD (odds ratio [OR]East Asian = 0.08 [0.02, 0.41]; ORSouth Asian = 0.05 [0.00, 0.81]), ADHD (OREast Asian = 0.27 [0.16, 0.45]; ORSouth Asian = 0.09 [0.03, 0.30]) and anxiety (OREast Asian = 0.21 [0.11, 0.39]; ORSouth Asian = 0.12 [0.05, 0.32]) than White youth after accounting for psychiatric trait levels. CONCLUSIONS: These results suggest a discrepancy between trait levels of OCD, ADHD and anxiety and rates of diagnoses for East Asian and South Asian youth. This discrepancy may be due to increased barriers for ethnically diverse youth to access mental health care. Efforts to understand and mitigate these barriers in Canada are needed.

We know that there is there are differences in the prevalence of childhood mental illnesses by race/ethnic group, which may be related to disproportionate access to mental health care. What is unknown is whether there this difference in prevalence is related to differences in the presence of symptoms for mental illness or whether children and youth from marginalized racial/ethnic groups have symptoms but are not getting diagnosed. This information is needed to understand the degree to which children and youth from marginalized race/ethnicity groups are accessing mental health care in Canada. We tested the differences in reported symptoms and diagnosis of three common and impairing childhood-onset disorders (obsessive-compulsive disorder­OCD), attention-deficit/hyperactivity disorder­ADHD and anxiety disorders) in children and youth (6­17 years of age) living in Canada that were from three racial/ethnic groups: White, South Asian and East Asian. East Asian and South Asian youth reported significantly higher levels of OCD and anxiety traits than White youth. However, East Asian and South Asian youth were significantly less likely than White youth to have a reported diagnosis of OCD, ADHD or anxiety even after accounting for symptom levels for each disorder. Our findings suggest that East and South Asian children are less likely than White children to get a diagnosis for common mental illness even if they have symptoms of that mental illness. This gap in receiving a diagnosis might be because of more barriers to mental health care for children and youth from marginalized racial/ethnic groups but we need more research to pinpoint the cause.

The genetic architecture of youth anxiety: a study protocol.

BACKGROUND: Anxiety disorders are the most common psychiatric problems among Canadian youth and typically have an onset in childhood or adolescence. They are characterized by high rates of relapse and chronicity, often resulting in substantial impairment across the lifespan. Genetic factors play an important role in the vulnerability toward anxiety disorders. However, genetic contribution to anxiety in youth is not well understood and can change across developmental stages. Large-scale genetic studies of youth are needed with detailed assessments of symptoms of anxiety disorders and their major comorbidities to inform early intervention or preventative strategies and suggest novel targets for therapeutics and personalization of care. METHODS: The Genetic Architecture of Youth Anxiety (GAYA) study is a Pan-Canadian effort of clinical and genetic experts with specific recruitment sites in Calgary, Halifax, Hamilton, Toronto, and Vancouver. Youth aged 10-19 (n = 13,000) will be recruited from both clinical and community settings and will provide saliva samples, complete online questionnaires on demographics, symptoms of mental health concerns, and behavioural inhibition, and complete neurocognitive tasks. A subset of youth will be offered access to a self-managed Internet-based cognitive behavioral therapy resource. Analyses will focus on the identification of novel genetic risk loci for anxiety disorders in youth and assess how much of the genetic risk for anxiety disorders is unique or shared across the life span. DISCUSSION: Results will substantially inform early intervention or preventative strategies and suggest novel targets for therapeutics and personalization of care. Given that the GAYA study will be the biggest genomic study of anxiety disorders in youth in Canada, this project will further foster collaborations nationally and across the world.

Is irritability multidimensional: Psychometrics of The Irritability and Dysregulation of Emotion Scale (TIDES-13).

Irritability is a common, impairing, and potentially multifaceted manifestation of psychopathology. We designed The Irritability and Dysregulation of Emotion Scale (TIDES-13) to determine whether various expressions of irritability in children and youth form multiple subdimensions with distinct correlates. We administered parent-report (n = 3875, mean age = 8.9) and youth self-report (n = 579, mean age = 15.1) versions of TIDES-13 in a population and community-based sample. We conducted exploratory/confirmatory factor analyses and regression analyses to examine the dimensionality of TIDES-13 and the associations of the scale with age, gender, anxiety, depression, ODD, ADHD traits, and the Affective Reactivity Index (ARI). A higher-order model with a global irritability dimension and four subdimensions, including proneness to anger (PA), internalized negative emotional reactivity (iNER), externalized negative emotional reactivity (eNER), and reactive aggression (RA), showed good to excellent fit in both parent-report and self-report. The global irritability dimension showed excellent internal reliability (⍵Total; parent-report = 0.97, ⍵Total; self-report = 0.95), explained a majority of the item variance (⍵Hierarchical; parent-report = 0.94, ⍵Hierarchical; self-report = 0.90), and was moderately correlated with the ARI (rparent = 0.68, rself = 0.77). Subdimensions PA, eNER, and RA were negatively associated with age in males, whereas iNER was positively associated with age in females. Traits of ODD and ADHD were associated primarily with the global irritability dimension, whereas iNER was strongly associated with anxiety and depression traits over and above the global irritability dimension. Our results support a unidimensional interpretation of irritability in a population sample. However, limited evidence of specific behavioral, age, and sex correlates with particular irritability subdimensions may warrant further investigation.

The Distinction Between Social Connectedness and Support When Examining Depressive Symptoms Among Children and Adolescents During the COVID-19 Pandemic.

Childhood depression is associated with significant social and functional impairment, suicide risk, and persistence throughout adulthood. Recent evidence demonstrates that social connectedness and social support may serve as protective factors against the development of depression. The current study aimed to examine the effect of change in social connectedness and social support on depressive symptoms among children and adolescents during the COVID-19 pandemic. Hierarchical regression was performed. Results indicated that parent-reported measures of change in social connectedness were inversely associated with depressive symptom severity, and could significantly predict future depressive symptom severity. In contrast, parent-reported measures of social support (i.e., from family and friends) did not significantly predict future depressive symptom severity. The presence of a pre-COVID psychiatric and/or neurodevelopmental diagnosis and baseline depressive symptom severity were also important factors associated with future depressive symptom severity. The findings suggest that an awareness of the presence of social supports (i.e., family or friends) is not sufficient for children to feel connected, but rather the mechanisms of social relationships are crucial. As our approach to public health restrictions evolves, the risk transmission of COVID-19 should be carefully balanced with the risks associated with decreased connectedness among youth.

Latin American Trans-ancestry INitiative for OCD genomics (LATINO): Study protocol.

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric disorder. Worldwide, its prevalence is ~2% and its etiology is mostly unknown. Identifying biological factors contributing to OCD will elucidate underlying mechanisms and might contribute to improved treatment outcomes. Genomic studies of OCD are beginning to reveal long-sought risk loci, but >95% of the cases currently in analysis are of homogenous European ancestry. If not addressed, this Eurocentric bias will result in OCD genomic findings being more accurate for individuals of European ancestry than other ancestries, thereby contributing to health disparities in potential future applications of genomics. In this study protocol paper, we describe the Latin American Trans-ancestry INitiative for OCD genomics (LATINO, https://www.latinostudy.org). LATINO is a new network of investigators from across Latin America, the United States, and Canada who have begun to collect DNA and clinical data from 5000 richly phenotyped OCD cases of Latin American ancestry in a culturally sensitive and ethical manner. In this project, we will utilize trans-ancestry genomic analyses to accelerate the identification of OCD risk loci, fine-map putative causal variants, and improve the performance of polygenic risk scores in diverse populations. We will also capitalize on rich clinical data to examine the genetics of treatment response, biologically plausible OCD subtypes, and symptom dimensions. Additionally, LATINO will help elucidate the diversity of the clinical presentations of OCD across cultures through various trainings developed and offered in collaboration with Latin American investigators. We believe this study will advance the important goal of global mental health discovery and equity.

The role of parenting practices in parent and child mental health over time.

BACKGROUND: Parent and child mental health has suffered during the pandemic and transition phase. Structured and shared parenting may be intervention targets beneficial to families who are struggling with parent or child mental health challenges. AIMS: First, we investigated associations between structured and shared parenting and parent depression symptoms. Second, we investigated associations between structured and shared parenting and depression, hyperactivity/inattention and irritability symptoms in children. METHOD: A total of 1027 parents in two-parent households (4797 observations total; 85.1% mothers) completed online surveys about themselves and their children (aged 2-18 years) from April 2020 to July 2022. Structured parenting and shared parenting responsibilities were assessed from April 2020 to November 2021. Symptoms of parent depression, child depression, child hyperactivity and inattention, child irritability, and child emotional and conduct problems were assessed repeatedly (one to 14 times; median of four times) from April 2020 to July 2022. RESULTS: Parents who reported higher levels of shared parenting responsibilities had lower depression symptoms (ß = -0.09 to -0.32, all P < 0.01) longitudinally. Parents who reported higher levels of shared parenting responsibilities had children with fewer emotional problems (ages 2-5 years; ß = -0.07, P < 0.05), fewer conduct problems (ages 2-5 years; ß = -0.09, P < 0.01) and less irritability (ages 13-18 years; ß = -0.27, P < 0.001) longitudinally. Structured parenting was associated with fewer conduct problems (ages 2-5 years; ß = -0.05, P < 0.05). CONCLUSIONS: Shared parenting is beneficial for parent and child mental health, even under chaotic or inflexible life conditions. Structured parenting is beneficial for younger children.

Trans-ancestry meta-analysis of genome wide association studies of inhibitory control.

Deficits in effective executive function, including inhibitory control are associated with risk for a number of psychiatric disorders and significantly impact everyday functioning. These complex traits have been proposed to serve as endophenotypes, however, their genetic architecture is not yet well understood. To identify the common genetic variation associated with inhibitory control in the general population we performed the first trans-ancestry genome wide association study (GWAS) combining data across 8 sites and four ancestries (N = 14,877) using cognitive traits derived from the stop-signal task, namely - go reaction time (GoRT), go reaction time variability (GoRT SD) and stop signal reaction time (SSRT). Although we did not identify genome wide significant associations for any of the three traits, GoRT SD and SSRT demonstrated significant and similar SNP heritability of 8.2%, indicative of an influence of genetic factors. Power analyses demonstrated that the number of common causal variants contributing to the heritability of these phenotypes is relatively high and larger sample sizes are necessary to robustly identify associations. In Europeans, the polygenic risk for ADHD was significantly associated with GoRT SD and the polygenic risk for schizophrenia was associated with GoRT, while in East Asians polygenic risk for schizophrenia was associated with SSRT. These results support the potential of executive function measures as endophenotypes of neuropsychiatric disorders. Together these findings provide the first evidence indicating the influence of common genetic variation in the genetic architecture of inhibitory control quantified using objective behavioural traits derived from the stop-signal task.

Gene copy number variation and pediatric mental health/neurodevelopment in a general population.

We assessed the relationship of gene copy number variation (CNV) in mental health/neurodevelopmental traits and diagnoses, physical health and cognition in a community sample of 7100 unrelated children and youth of European or East Asian ancestry (Spit for Science). Clinically significant or susceptibility CNVs were present in 3.9% of participants and were associated with elevated scores on a continuous measure of attention-deficit/hyperactivity disorder (ADHD) traits (P = 5.0 × 10-3), longer response inhibition (a cognitive deficit found in several mental health and neurodevelopmental disorders; P = 1.0 × 10-2) and increased prevalence of mental health diagnoses (P = 1.9 × 10-6, odds ratio: 3.09), specifically ADHD, autism spectrum disorder anxiety and learning problems/learning disorder (P's < 0.01). There was an increased burden of rare deletions in gene-sets related to brain function or expression in brain associated with more ADHD traits. With the current mental health crisis, our data established a baseline for delineating genetic contributors in pediatric-onset conditions.

Latin American Trans-ancestry INitiative for OCD genomics (LATINO): Study Protocol.

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric disorder. Worldwide, its prevalence is ~2% and its etiology is mostly unknown. Identifying biological factors contributing to OCD will elucidate underlying mechanisms and might contribute to improved treatment outcomes. Genomic studies of OCD are beginning to reveal long-sought risk loci, but >95% of the cases currently in analysis are of homogenous European ancestry. If not addressed, this Eurocentric bias will result in OCD genomic findings being more accurate for individuals of European ancestry than other ancestries, thereby contributing to health disparities in potential future applications of genomics. In this study protocol paper, we describe the Latin American Trans-ancestry INitiative for OCD genomics (LATINO, www.latinostudy.org). LATINO is a new network of investigators from across Latin America, the United States, and Canada who have begun to collect DNA and clinical data from 5,000 richly-phenotyped OCD cases of Latin American ancestry in a culturally sensitive and ethical manner. In this project, we will utilize trans-ancestry genomic analyses to accelerate the identification of OCD risk loci, fine-map putative causal variants, and improve the performance of polygenic risk scores in diverse populations. We will also capitalize on rich clinical data to examine the genetics of treatment response, biologically plausible OCD subtypes, and symptom dimensions. Additionally, LATINO will help elucidate the diversity of the clinical presentations of OCD across cultures through various trainings developed and offered in collaboration with Latin American investigators. We believe this study will advance the important goal of global mental health discovery and equity.

Disruption to Education During COVID-19: School Nonacademic Factors Are Associated with Children's Mental Health.

OBJECTIVE: Few studies have examined aspects of the school environment, beyond modality, as contributors to child and youth mental health during the coronavirus pandemic. We investigated associations between nonacademic school experiences and children's mental health. METHODS: Parents of children ages 6 to 18 years completed online surveys about school experiences (November 2020) and mental health (February/March 2021). Parent-reported and child-reported school experiences (i.e., nonacademic factors) included school importance, adapting to public health measures, and school connectedness. Children's mental health symptoms of depression, anxiety, inattention, and hyperactivity were collected using standardized parent-reported measures. RESULTS: Children's (N = 1052) self-reported and parent-reported nonacademic factors were associated with mental health outcomes, after adjusting for demographics and previous mental health. Lower importance, worse adapting to school changes, and less school connectedness were associated with greater depressive symptoms ( B = -4.68, CI [-6.04, -3.67] to - 8.73 CI [-11.47, 5.99]). Lower importance and worse adapting were associated with greater anxiety symptoms ( B = - 0.83 , CI [-1.62, -0.04] to -1.04 CI [-1.60, -0.48]). Lower importance was associated with greater inattention (B = -4.75, CI [-6.60, -2.90] to -6.37, CI [-11.08, -7.50]). Lower importance and worse adapting were associated with greater hyperactivity (B = -1.86, CI [-2.96, -0.77] to -4.71, CI [-5.95, -3.01]). CONCLUSION: Schools offer learning opportunities that extend beyond curriculum content and are a primary environment where children and youth develop connections with others. These aspects of school, beyond academics, should be recognized as key correlates of child and youth mental health.

Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder: Shared or Unique Neurocognitive Profiles?

Attention-deficit/hyperactivity (ADHD) and autism spectrum (ASD) disorders are commonly co-occurring conditions characterized by neurocognitive impairments. Few studies have directly compared neurocognitive profiles in ADHD and ASD and fewer still have controlled for comorbidity of ADHD and ASD. All direct comparisons have been in clinic samples, leaving the question of generalizability of results unaddressed. We compared neurocognitive performance in clinically ascertained ASD (n = 261) and ADHD (n = 423) cases and controls (n = 162), 6.0-17.9 years of age. We also compared ASD (n = 190) and ADHD (n = 926) cases ascertained in the community with controls (n = 14,842) of similar age. Using the stop-signal task (SST), we measured response inhibition (stop-signal reaction time-SSRT), sustained attention (defined as reaction time variability-RTV), and reaction time (RT). We controlled for comorbidity using ADHD and ASD trait scores and categorically-defined ADHD. Compared with controls, both clinic ADHD and ASD had significantly longer SSRT and RTV than controls and did not differ from each other. ADHD traits accounted for neurocognitive impairment in ASD, but not vice versa. There were no group differences for RT. Similar patterns of neurocognitive impairment were observed in the community sample. In the largest direct comparison of ADHD and ASD to date, we found impaired response inhibition and sustained attention in both disorders. However, neurocognitive impairment in ASD was almost completely accounted for by comorbid ADHD. Results generalized in the community sample indicating that referral bias alone did not drive results. Response inhibition and sustained attention likely play a role in ADHD and ASD.

School and learning contexts during the COVID-19 pandemic: Implications for child and youth mental health.

Despite significant disruption to school during the COVID-19 pandemic, research on the impact on children is sparse. This study examines in-person and virtual learning contexts and the impact of school format on mental health (MH). Children and adolescents were recruited from community and clinical settings. Parents and children completed prospective online surveys about school experiences (November 2020) and MH symptoms (February/March 2021), including school format and activities. Standardized measures of depression, anxiety, inattention, and hyperactivity were collected. Hierarchical regression analyses tested associations between school format and MH. Children (N = 1011; aged 6-18 years) attending school in-person (n = 549) engaged in high levels of participation in COVID-19 health measures and low levels of social learning activities. Learning online in high school was associated with greater MH symptoms (B = -2.22, CI[-4.32,-.12] to B = -8.18, CI[-15.59,-.77]). Children with no previous MH condition that attended school virtually experienced a similar magnitude of MH symptoms as those with previous MH conditions. However, children who attended school in a hybrid in-person format, with no previous MH condition, experienced less hyperactivity as same-age peers with prior MH problems (B = -8.08, CI[1.58,14.58]). Children's learning environments looked very different compared to before the pandemic. Removing children from school environments and limiting opportunities that support their MH, such as social learning activities, is problematic. Efforts to address the learning contexts to protect the mental health of children are needed.

Meta-analysis of genome-wide association studies of hoarding symptoms in 27,537 individuals.

Hoarding Disorder (HD) is a mental disorder characterized by persistent difficulties discarding or parting with possessions, often resulting in cluttered living spaces, distress, and impairment. Its etiology is largely unknown, but twin studies suggest that it is moderately heritable. In this study, we pooled phenotypic and genomic data from seven international cohorts (N = 27,537 individuals) and conducted a genome wide association study (GWAS) meta-analysis of parent- or self-reported hoarding symptoms (HS). We followed up the results with gene-based and gene-set analyses, as well as leave-one-out HS polygenic risk score (PRS) analyses. To examine a possible genetic association between hoarding symptoms and other phenotypes we conducted cross-trait PRS analyses. Though we did not report any genome-wide significant SNPs, we report heritability estimates for the twin-cohorts between 26-48%, and a SNP-heritability of 11% for an unrelated sub-cohort. Cross-trait PRS analyses showed that the genetic risk for schizophrenia and autism spectrum disorder were significantly associated with hoarding symptoms. We also found suggestive evidence for an association with educational attainment. There were no significant associations with other phenotypes previously linked to HD, such as obsessive-compulsive disorder, depression, anxiety, or attention-deficit hyperactivity disorder. To conclude, we found that HS are heritable, confirming and extending previous twin studies but we had limited power to detect any genome-wide significant loci. Much larger samples will be needed to further extend these findings and reach a "gene discovery zone". To move the field forward, future research should not only include genetic analyses of quantitative hoarding traits in larger samples, but also in samples of individuals meeting strict diagnostic criteria for HD, and more ethnically diverse samples.

Hyperfocus or flow? Attentional strengths in autism spectrum disorder.

The comorbidity of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) diagnoses is well established. An ASD diagnosis is associated with elevated ADHD traits and symptoms, as well as strengths in attention. In the ASD literature, attentional strengths have been described as maladaptive (e.g., hyperfocus), in contrast with positive portrayals in the typically developing population (e.g., flow). The objective of this study was to (1) compare profiles of attentional strengths and weaknesses in ASD and ADHD and (2) determine whether attentional strengths in ASD are associated with impairment, poorer cognitive flexibility, and perseveration/perfectionism. In a community sample of 5,744 children and youth, 131 children were reported as having a diagnosis of ASD (mean age 10.3 years) and 346 children were reported as having a diagnosis of ADHD (mean age 10.7 years). We used the Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviors (SWAN) rating scale to calculate attentional and hyperactive/impulse control strength and weakness counts and scores. The Autism-Spectrum Quotient Switching factor served as a measure of cognitive flexibility. Impairment was assessed with the Columbia Impairment Scale. We used the symmetry/ordering factor on the Toronto Obsessive-Compulsive Scale as a measure of perseveration/perfectionism. No differences were found between the ADHD and ASD groups in SWAN weakness scores, symptoms, or hyperactive/impulse control strengths; however, autistic children had higher rates of attentional strengths [odds ratio: 5.7, 95% CI (2.8, 11.6), p < 0.0001]. Post-hoc pairwise testing identified four attentional strengths with significantly higher rates in ASD than in ADHD. Attentional strength scores were not associated with impairment or poor cognitive flexibility, but predicted levels of perseveration/perfectionism. The effect of attentional strengths on impairment and cognitive flexibility did not differ between autistic and Control children, but the higher perseveration/perfectionism scores seen in ASD were not found in Control children. ASD is associated with a pattern of attentional strengths that is not found in ADHD Characterizing the full range of attentional abilities in autistic children may explain variability in outcomes such as quality-of-life indicators and identify protective factors, providing targets for strength-based behavioral interventions. The clinical and etiological implications of the subgroup of autistic children with attentional strengths require further investigation.

Participating in extracurricular activities and school sports during the COVID-19 pandemic: Associations with child and youth mental health.

In Ontario, Canada, school extracurricular activities and sports were modified or canceled for a prolonged period due to public health restrictions resulting from the COVID-19 pandemic. The present study aims to examine the association of changes to extracurricular and sport participation and child and youth mental health. Data were collected on child and youth mental health symptoms (n = 908) and participation in extracurricular activities and sports in the 2019-2020 and 2020-2021 academic years. Results indicated that pre-COVID (2019-2020) participation in either extracurricular activities or sports was associated with reduced anxiety, inattention, and hyperactivity during the pandemic (ß range -0.08 to -0.11, p < 0.05). Participation in either extracurricular activities or sports during-COVID (2020-2021) was associated with lower depressive symptoms (ß range -0.09 to -0.10, p < 0.05). Findings suggest that participation in extracurricular activities and/or school sports both before or during the COVID-19 pandemic were associated with better mental health outcomes in children and youth. Implications of this work consider future situations where restrictions on extracurricular and sport participation are reinstated and the impact of child and youth mental health.

Obsessive-compulsive disorder in children and youth: neurocognitive function in clinic and community samples.

BACKGROUND: Neurocognitive impairments are common in OCD, although not well studied in children and youth with the disorder. METHOD: Using the stop-signal task (SST), we measured response inhibition (stop-signal reaction time-SSRT), sustained attention (reaction time variability-RTV), reaction time (RT), and performance monitoring (post-error slowing-PES) in OCD cases and controls from two samples of children and youth. A Clinic OCD group (n = 171, aged 7-17 years) was recruited from a specialty clinic after rigorous assessment. A typically developing (Clinic TD, n = 157) group was enlisted through advertisement. A community OCD sample (Community OCD, n = 147) and controls (Community TD n = 13,832, aged 6-17 years) were recruited at a science museum. We also identified a community group with high OCD traits without an OCD diagnosis (Community High Trait; n = 125). RESULTS: Clinic OCD participants had longer SSRT and greater RTV than Clinic TD. These effects were greater in younger OCD participants and, for SSRT, in those on medication for OCD. The Community OCD group did not differ from Controls but was similar to the Clinic OCD group in ADHD and ASD comorbidity and medication usage. The Community High Trait group had longer SSRT and atypical PES suggesting that symptom severity predicts neurocognitive function. No group differences were found in RT. CONCLUSIONS: In the largest study of neurocognitive performance in children with OCD to date, we found impaired response inhibition and sustained attention in OCD participants in comparison to typically developing peers. Performance was worse in younger OCD participants. In the community sample, participants with high OCD trait scores but no OCD diagnosis had impaired response inhibition and error processing, suggesting that OCD might be under-recognized.