Characterizing Developmental Trajectories and the Role of Neuropsychiatric Genetic Risk Variants in Early-Onset Depression

Investigating the neurodevelopmental correlates of early adolescent-onset emotional problems

BACKGROUND

Emotional problems (EPs) increase sharply after mid-adolescence. Earlier EPs are associated with poorer long-term outcomes, and their underlying mechanisms may differ to later-onset EPs. Given an established relationship between ADHD, autism, and later depression, we aimed to examine associations between neurodevelopmental conditions and correlates and early adolescent-onset EPs.

METHODS

Adolescents in two UK population cohorts, Avon Longitudinal Study of Parents and Children (ALSPAC) and Millennium Cohort Study (MCS), were included. Individuals scoring >6 on the Strengths and Difficulties Questionnaire (SDQ) emotional problems subscale between ages 11-14 were defined as having early adolescent-onset EP, whilst those scoring >6 for the first time at 16-25 were defined as having later-onset EP. We tested associations between early adolescent-onset EP (total cases = 887, controls = 19,582) and ICD-10/DSM-5 neurodevelopmental conditions and known correlates, including: sex, birth complications, low cognitive ability, special educational needs (SEND), and epilepsy. Analyses were conducted separately in ALSPAC and MCS then meta-analysed.

RESULTS

In the meta-analysis of both cohorts, early adolescent-onset EPs were associated with female sex and greater likelihood of low cognitive ability, SEND, autism, ADHD, and reading difficulties. Compared to later-onset EP, early adolescent-onset EPs were associated with male sex, low cognitive ability, SEND, epilepsy, ASD, ADHD, and reading difficulties.

LIMITATIONS

A clinical definition of depression/anxiety was available only in ALSPAC, instead we primarily defined EP via questionnaires, which capture a broader phenotype.

CONCLUSIONS

Individuals with early adolescent-onset EP are likely to have a co-occurring neurodevelopmental condition. Clinicians should consider assessing for neurodevelopmental conditions in young adolescents with EPs.

Clinical and sociodemographic features of the Texas resilience against depression (T-RAD) study: Findings from the initial cohort

OBJECTIVE

The burden of major depressive disorder is compounded by a limited understanding of its risk factors, the limited efficacy of treatments, and the lack of precision approaches to guide treatment selection. The Texas Resilience Against Depression (T-RAD) study was designed to explore the etiology of depression by collecting comprehensive socio-demographic, clinical, behavioral, neurophysiological/neuroimaging, and biological data from depressed individuals (D2K) and youth at risk for depression (RAD).

METHODS

This report details the baseline sociodemographic, clinical, and functional features from the initial cohort (D2K N = 1040, RAD N = 365).

RESULTS

Of the total T-RAD sample, n = 1078 (76.73 %) attended ≥2 in-person visits, and n = 845 (60.14 %) attended ≥4 in-person visits. Most D2K (84.82 %) had a primary diagnosis of any depressive disorder, with a bipolar disorder diagnosis being prevalent (13.49 %). RAD participants (75.89 %) did not have a psychiatric diagnosis, but other non-depressive diagnoses were present. D2K participants had 9-item Patient Health Questionnaire scores at or near the moderate range (10.58 ± 6.42 > 24 yrs.; 9.73 ± 6.12 10-24 yrs). RAD participants were in the non-depressed range (2.19 ± 2.65). While the age ranges in D2K and RAD differ, the potential to conduct analyses that compare at-risk and depressed youth is a strength of the study. The opportunity to examine the trajectory of depressive symptoms in the D2K cohort over the lifespan is unique.

LIMITATIONS

As a longitudinal study, missing data were common.

CONCLUSION

T-RAD will allow data to be collected from multiple modalities on a clinically well-characterized sample. These data will drive important discoveries on diagnosis, treatment, and prevention of depression.

Effects of Neurodevelopmental Disorders on the Clinical Presentations and Therapeutic Outcomes of Children and Adolescents with Severe Mood Disorders: A Multicenter Observational Study

Individuals with neurodevelopmental disorders (NDDs) are more susceptible to developing severe or resistant mood disorders. However, they often face challenges in accessing specific treatments. To understand the barriers to treatment in this group, we conducted a secondary analysis of a multicenter observational study on 305 adolescents referred to specialized care (mean age 14.38 ± 0.13 years, 57% girls, 9% bipolar disorder, 91% depressive disorders). NDDs were categorized based on the number of co-occurring NDDs for each subject (none: 67%, one: 18%, two: 7%, three: 5%, four and more: 2%). We explored the predictive value of the number of NDDs on various clinical and therapeutic factors. The analysis revealed significant associations between the number of NDDs and the duration of mood symptoms, persistent irritability, associated disruptive behavioral disorders, lower scores on the Children's Global Assessment Scale (CGAS) at baseline, and polypharmacy. The number of NDDs did not correlate with the use of antidepressants, the Clinical Global Impression-Improvement scale (CGI-I) at discharge, or changes in the CGAS score during the stay. The challenges in distinguishing mood disorders from chronic emotional and behavioral difficulties may contribute to the difficulties in accessing specific care for mood disorders. These results suggest that treatments for mood disorders demonstrate comparable effectiveness when provided regardless of the associations with NDDs.

Impact of air pollution exposure on the severity of major depressive disorder: Results from the DeprAir study

BACKGROUND

Major depressive disorder (MDD) is one of the most prevalent medical conditions worldwide. Different factors were found to play a role in its etiology, including environmental ones (e.g., air pollution). The aim of this study was to evaluate the association between air pollution exposure and MDD severity.

METHODS

Four hundred sixteen MDD subjects were recruited. Severity of MDD and functioning were evaluated through five rating scales: Montgomery-Asberg Depression Rating Scale (MADRS), Hamilton Depression Rating Scale (HAMD), Clinical Global Impression (CGI), Global Assessment of Functioning (GAF), and Sheehan Disability Scale (SDS). Daily mean estimates of particulate matter with diameter ≤10 (PM10) and 2.5 μm (PM2.5), nitrogen dioxide (NO2), and apparent temperature (AT) were estimated based on subjects' residential addresses. Daily estimates of the 2 weeks preceding recruitment were averaged to obtain cumulative exposure. Multivariate linear and ordinal regression models were applied to assess the associations between air pollutants and MDD severity, overall and stratifying by hypersusceptibility and AT.

RESULTS

Two-thirds of subjects were women and one-third had a family history of depression. Most women had depression with symptoms of anxiety, while men had predominantly melancholic depression. NO2 exposure was associated with worsening of MDD severity (HAMD: β = 1.94, 95% confidence interval [CI], [0.41-3.47]; GAF: β = -1.93, 95% CI [-3.89 to 0.02]), especially when temperatures were low or among hypersusceptible subjects. PM exposure showed an association with MDD severity only in these subgroups.

CONCLUSIONS

Exposure to air pollution worsens MDD severity, with hypersusceptibility and lower temperatures being exacerbating factors.

Genetic Architectures of Adolescent Depression Trajectories in 2 Longitudinal Population Cohorts

Importance

Adolescent depression is characterized by diverse symptom trajectories over time and has a strong genetic influence. Research has determined genetic overlap between depression and other psychiatric conditions; investigating the shared genetic architecture of heterogeneous depression trajectories is crucial for understanding disease etiology, prediction, and early intervention.

Objective

To investigate univariate and multivariate genetic risk for adolescent depression trajectories and assess generalizability across ancestries.

Design, Setting, and Participants

This cohort study entailed longitudinal growth modeling followed by polygenic risk score (PRS) association testing for individual and multitrait genetic models. Two longitudinal cohorts from the US and UK were used: the Adolescent Brain and Cognitive Development (ABCD; N = 11 876) study and the Avon Longitudinal Study of Parents and Children (ALSPAC; N = 8787) study. Included were adolescents with genetic information and depression measures at up to 8 and 4 occasions, respectively. Study data were analyzed January to July 2023.

Main Outcomes and Measures

Trajectories were derived from growth mixture modeling of longitudinal depression symptoms. PRSs were computed for depression, anxiety, neuroticism, bipolar disorder, schizophrenia, attention-deficit/hyperactivity disorder, and autism in European ancestry. Genomic structural equation modeling was used to build multitrait genetic models of psychopathology followed by multitrait PRS. Depression PRSs were computed in African, East Asian, and Hispanic ancestries in the ABCD cohort only. Association testing was performed between all PRSs and trajectories for both cohorts.

Results

A total sample size of 14 112 adolescents (at baseline: mean [SD] age, 10.5 [0.5] years; 7269 male sex [52%]) from both cohorts were included in this analysis. Distinct depression trajectories (stable low, adolescent persistent, increasing, and decreasing) were replicated in the ALSPAC cohort (6096 participants; 3091 female [51%]) and ABCD cohort (8016 participants; 4274 male [53%]) between ages 10 and 17 years. Most univariate PRSs showed significant uniform associations with persistent trajectories, but fewer were significantly associated with intermediate (increasing and decreasing) trajectories. Multitrait PRSs-derived from a hierarchical factor model-showed the strongest associations for persistent trajectories (ABCD cohort: OR, 1.46; 95% CI, 1.26-1.68; ALSPAC cohort: OR, 1.34; 95% CI, 1.20-1.49), surpassing the effect size of univariate PRS in both cohorts. Multitrait PRSs were associated with intermediate trajectories but to a lesser extent (ABCD cohort: hierarchical increasing, OR, 1.27; 95% CI, 1.13-1.43; decreasing, OR, 1.23; 95% CI, 1.09-1.40; ALSPAC cohort: hierarchical increasing, OR, 1.16; 95% CI, 1.04-1.28; decreasing, OR, 1.32; 95% CI, 1.18-1.47). Transancestral genetic risk for depression showed no evidence for association with trajectories.

Conclusions and Relevance

Results of this cohort study revealed a high multitrait genetic loading of persistent symptom trajectories, consistent across traits and cohorts. Variability in univariate genetic association with intermediate trajectories may stem from environmental factors. Multitrait genetics may strengthen depression prediction models, but more diverse data are needed for generalizability.

The Prospective Predictive Power of Parent-Reported Personality Traits and Facets in First-Onset Depression in Adolescent Girls

Certain personality traits and facets are well-known risk factors that predict first-onset depression during adolescence. However, prior research predominantly relied on self-reported data, which has limitations as a source of personality information. Reports from close informants have the potential to increase the predictive power of personality on first-onsets of depression in adolescents. With easy access to adolescents' behaviors across settings and time, parents may provide important additional information about their children's personality. The same personality trait(s) and facet(s) rated by selves (mean age 14.4 years old) and biological parents at baseline were used to prospectively predict depression onsets among 442 adolescent girls during a 72-month follow-up. First, bivariate logistic regression was used to examine whether parent-reported personality measures predicted adolescent girls' depression onsets; then multivariate logistic regression was used to test whether parent reports provided additional predictive power above and beyond self-reports of same trait or facet. Parent-reported personality traits and facets predicted adolescents' depression onsets, similar to findings using self-reported data. After controlling for the corresponding self-report measures, parent-reported higher openness (at the trait level) and higher depressivity (at the facet-level) incrementally predicted first-onset of depression in the sample. Findings demonstrated additional variance contributed by parent-reported personality measures and validated a multi-informant approach in using personality to prospectively predict onsets of depression in adolescent girls.

Childhood correlates and young adult outcomes of trajectories of emotional problems from childhood to adolescence

BACKGROUND

Emotional problems, especially anxiety, have become increasingly common in recent generations. Few population-based studies have examined trajectories of emotional problems from early childhood to late adolescence or investigated differences in psychiatric and functional outcomes.

METHODS

Using the Avon Longitudinal Study of Parents and Children (ALSPAC, n = 8286, 50.4% male), we modeled latent class growth trajectories of emotional problems, using the parent-reported Strength and Difficulties Questionnaire emotional scale (SDQ-E) on seven occasions (4-17 years). Psychiatric outcomes in young adulthood (21-25 years) were major depressive disorder (MDD), generalized anxiety disorder (GAD), and self-harm. Functional outcomes were exam attainment, educational/occupational status, and social relationship quality.

RESULTS

We identified four classes of emotional problems: low (67.0%), decreasing (18.4%), increasing (8.9%), and persistent (5.7%) problems. Compared to those in the low class, individuals with decreasing emotional problems were not at elevated risk of any poor adult outcome. Individuals in the increasing and persistent classes had a greater risk of adult MDD (RR: 1.59 95% CI 1.13-2.26 and RR: 2.25 95% CI 1.49-3.41) and self-harm (RR: 2.37 95% CI 1.91-2.94 and RR: 1.87 95% CI 1.41-2.48), and of impairment in functional domains. Childhood sleep difficulties, irritability, conduct and neurodevelopmental problems, and family adversity were associated with a persistent course of emotional problems.

CONCLUSIONS

Childhood emotional problems were common, but those whose symptoms improved over time were not at increased risk for adverse adult outcomes. In contrast, individuals with persistent or adolescent-increasing emotional problems had a higher risk of mental ill-health and social impairment in young adulthood which was especially pronounced for those with persistent emotional problems.

Factors associated with chronic depressive symptoms across adolescence and young adulthood: a UK birth cohort study

AIMS

Identifying children and/or adolescents who are at highest risk for developing chronic depression is of utmost importance, so that we can develop more effective and targeted interventions to attenuate the risk trajectory of depression. To address this, the objective of this study was to identify young people with persistent depressive symptoms across adolescence and young adulthood and examine the prospective associations between factors and persistent depressive symptoms in young people.

METHODS

We used data from 6711 participants in the Avon Longitudinal Study of Parents and Children. Depressive symptoms were assessed at 12.5, 13.5, 16, 17.5, 21 and 22 years with the Short Mood and Feelings Questionnaire, and we further examined the influence of multiple biological, psychological and social factors in explaining chronic depressive symptoms.

RESULTS

Using latent class growth analysis, we identified four trajectories of depressive symptoms: persistent high, persistent low, persistent moderate and increasing high. After applying several logistic regression models, we found that loneliness and feeling less connected at school were the most relevant factors for chronic course of depressive symptoms.

CONCLUSIONS

Our findings contribute with the identification of those children who are at highest risk for developing chronic depressive symptoms.

Identification of liver transplant biopsy phenotypes associated with distinct liver biological markers and allograft survival

The intricate association between histologic lesions and circulating antihuman leucocyte antigen donor-specific antibodies (DSA) in liver transplantation (LT) requires further clarification. We conducted a probabilistic, unsupervised approach in a comprehensively well-annotated LT cohort to identify clinically relevant archetypes. We evaluated 490 pairs of LT biopsies with DSA testing from 325 recipients transplanted between 2010 and 2020 across 3 French centers and an external cohort of 202 biopsies from 128 recipients. Unsupervised archetypal analysis integrated all clinico-immuno-histologic parameters of each biopsy to identify biopsy archetypes. The median time after LT was 1.17 (interquartile range, 0.38-2.38) years. We identified 7 archetypes distinguished by clinico-immuno-histologic parameters: archetype #1: severe T cell-mediated rejection (15.9%); #2: chronic rejection with ductopenia (1.8%); #3: architectural and microvascular damages (3.5%); #4: (sub)normal (55.9%); #5: mild T cell-mediated rejection (4.9%); #6: acute antibody-mediated rejection (6.5%); and #7: chronic rejection with DSA (11.4%). Cell infiltrates vary in the archetype. These archetypes were associated with distinct liver biological markers and allograft outcomes. These findings remained consistent when stratified using the patient's age or indications for LT, with good performance in the external cohort (mean highest probability assignment = 0.58, standard deviation ± 0.17). In conclusion, we have identified clinically meaningful archetypes, providing valuable insights into the intricate DSA-histology association, which may help standardize liver allograft pathology classification.

Aberrant Hippocampal Development in Early-onset Mental Disorders and Promising Interventions: Evidence from a Translational Study

Early-onset mental disorders are associated with disrupted neurodevelopmental processes during adolescence. The methylazoxymethanol acetate (MAM) animal model, in which disruption in neurodevelopmental processes is induced, mimics the abnormal neurodevelopment associated with early-onset mental disorders from an etiological perspective. We conducted longitudinal structural magnetic resonance imaging (MRI) scans during childhood, adolescence, and adulthood in MAM rats to identify specific brain regions and critical windows for intervention. Then, the effect of repetitive transcranial magnetic stimulation (rTMS) intervention on the target brain region during the critical window was investigated. In addition, the efficacy of this intervention paradigm was tested in a group of adolescent patients with early-onset mental disorders (diagnosed with major depressive disorder or bipolar disorder) to evaluate its clinical translational potential. The results demonstrated that, compared to the control group, the MAM rats exhibited significantly lower striatal volume from childhood to adulthood (all P <0.001). In contrast, the volume of the hippocampus did not show significant differences during childhood (P >0.05) but was significantly lower than the control group from adolescence to adulthood (both P <0.001). Subsequently, rTMS was applied to the occipital cortex, which is anatomically connected to the hippocampus, in the MAM models during adolescence. The MAM-rTMS group showed a significant increase in hippocampal volume compared to the MAM-sham group (P <0.01), while the volume of the striatum remained unchanged (P >0.05). In the clinical trial, adolescents with early-onset mental disorders showed a significant increase in hippocampal volume after rTMS treatment compared to baseline (P <0.01), and these volumetric changes were associated with improvement in depressive symptoms (r = - 0.524, P = 0.018). These findings highlight the potential of targeting aberrant hippocampal development during adolescence as a viable intervention for early-onset mental disorders with neurodevelopmental etiology as well as the promise of rTMS as a therapeutic approach for mitigating aberrant neurodevelopmental processes and alleviating clinical symptoms.

Negative Affect and Drinking among Indigenous Youth: Disaggregating Within- and Between-Person Effects

Negative affect (depression/anxiety) and alcohol use among Indigenous youth in Canada remain a concern for many communities. Disparate rates of these struggles are understood to be a potential outcome of colonization and subsequent intergenerational trauma experienced by individuals, families, and communities. Using a longitudinal design, we examined change in alcohol use and negative affect, and reciprocal associations, among a group of Indigenous adolescents. Indigenous youth (N = 117; 50% male; Mage=12.46-16.28; grades 6-10) from a remote First Nation in northern Quebec completed annual self-reported assessments on negative affect (depression/anxiety) and alcohol use. A Latent Curve Model with Structured Residuals (LCM-SR) was used to distinguish between- and within-person associations of negative affect and alcohol use. Growth models did not support change in depression/anxiety, but reports of drinking increased linearly. At the between-person level, girls reported higher initial levels of depression/anxiety and drinking; depression/anxiety were not associated with drinking. At the within-person level, drinking prospectively predicted increases in depression/anxiety but depression/anxiety did not prospectively predict drinking. When Indigenous adolescents reported drinking more alcohol than usual at one wave of assessment, they reported higher levels of negative affect than expected (given their average levels of depression/anxiety) at the following assessment. Our findings suggest that when Indigenous youth present for treatment reporting alcohol use, they should also be screened for negative affect (depression/anxiety). Conversely, if an Indigenous adolescent presents for treatment reporting negative affect, they should also be screened for alcohol use.

A prospective longitudinal study of multidomain resilience among youths with and without maltreatment histories

The majority of children with maltreatment histories do not go on to develop depression in their adolescent and adult years. These individuals are often identified as being "resilient", but this characterization may conceal difficulties that individuals with maltreatment histories might face in their interpersonal relationships, substance use, physical health, and/or socioeconomic outcomes in their later lives. This study examined how adolescents with maltreatment histories who exhibit low levels of depression function in other domains during their adult years. Longitudinal trajectories of depression (across ages 13-32) in individuals with (n = 3,809) and without (n = 8,249) maltreatment histories were modeled in the National Longitudinal Study of Adolescent to Adult Health. The same "Low," "increasing," and "declining" depression trajectories in both individuals with and without maltreatment histories were identified. Youths with maltreatment histories in the "low" depression trajectory reported lower romantic relationship satisfaction, more exposure to intimate partner and sexual violence, more alcohol abuse/dependency, and poorer general physical health compared to individuals without maltreatment histories in the same "low" depression trajectory in adulthood. Findings add further caution against labeling individuals as "resilient" based on a just single domain of functioning (low depression), as childhood maltreatment has harmful effects on a broad spectrum of functional domains.

Subtypes of Depressed Youth Admitted for Inpatient Psychiatric Care: A Latent Profile Analysis

Depressed youth frequently present with comorbid symptoms. Comorbidity is related to a poorer prognosis, including treatment resistance, academic problems, risk of suicide, and overall impairment. Studies examining the latent structure of depression support the notion of multiple presentations of depressed youth; however, it is unclear how these presentations are represented among acutely impaired youth. Participants (n = 457) in this naturalistic study were admitted to a psychiatric inpatient unit (Mean age = 14.33 years, SD = 1.94;76% female;46.6% Black/African-American). Selected subscales from the parent-report Behavior Assessment System for Children, Second Edition, were utilized as indicators in a latent profile analysis. Subgroups were validated based on their relationships with meaningful clinical correlates (e.g., family factors, discharge diagnosis) and further described by their associations with demographic variables. A five-class model provided the best balance of fit and parsimony. Subtypes of depressed youth included Predominantly Depressed (39.1%), Oppositional (28.2%), Severely Disruptive (12.3%), Anxious-Oppositional (11.6%), and Anxious-Withdrawn (8.8%). Comorbid symptoms were present in four of the five classes (60.9% of sample). High levels of externalizing symptoms were a prominent clinical feature associated with three classes (52.1% of the sample). Construct validity of the respective classes was demonstrated by differential association with clinical correlates, family characteristics, and demographics. Findings suggest that depressed youth presenting for acute inpatient psychiatric care displayed varied clinical presentations. The identified latent groups aligned with existing research reflecting comorbidity with anxiety, inattention, and externalizing disorders. Findings underscore the need for an increased clinical appreciation of comorbidity and encourage more targeted and effective prevention and treatment strategies.

Epigenetic mechanisms in depression: Implications for pathogenesis and treatment

The risk of depression is influenced by both genetic and environmental factors. It has been suggested that epigenetic mechanisms may mediate the risk of depression following exposure to adverse life events. Epigenetics encompasses stable alterations in gene expression that are controlled through transcriptional, post-transcriptional, translational, or post-translational processes, including DNA modifications, chromatin remodeling, histone modifications, RNA modifications, and non-coding RNA (ncRNA) regulation, without any changes in the DNA sequence. In this review, we explore recent research advancements in the realm of epigenetics concerning depression. Furthermore, we evaluate the potential of epigenetic changes as diagnostic and therapeutic biomarkers for depression.

Attention-Deficit/Hyperactivity Disorder and Major Depressive Disorder: Evidence From Multiple Genetically Informed Designs

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) and major depressive disorder (MDD) are two highly prevalent disorders that frequently co-occur. Prior evidence from genetic and cohort studies supports an association between ADHD and MDD. However, the direction and mechanisms underlying their association remain unclear. As onset of ADHD occurs in early life, it has been hypothesized that ADHD may cause MDD.

METHODS

We examined the association of ADHD with MDD using 3 different genetically informed methods to disentangle causality from confounding: 1) a nationwide longitudinal register-based full sibling comparison (N = 1,018,489) adjusting for shared familial confounding; 2) a prospective co-twin control study comprising 16,477 twins (5084 monozygotic and 11,393 dizygotic); and 3) a two-sample Mendelian randomization analysis using the largest available ADHD (N = 225,534) and MDD (N = 500,199) genome-wide association study summary statistics, adjusting for correlated and uncorrelated horizontal pleiotropy.

RESULTS

Sibling and twin comparisons indicated that individuals with ADHD have an increased risk for subsequent development of MDD (hazard ratio = 4.12 [95% CI 3.62-4.69]) after adjusting for shared genetic and familial factors and that ADHD scores endorsed by parents are positively associated with subsequent MDD scores at ages 15 and 18 years (b = 0.07 [95% CI 0.05-0.08] and b = 0.09 [95% CI 0.08-0.11], respectively). Mendelian randomization analyses showed that genetic liability for ADHD is causally related to MDD (odds ratio = 1.15 [95% CI 1.08-1.23]).

CONCLUSIONS

Our study provides consistent results across 3 different genetically informative approaches, strengthening the hypothesis that ADHD is causally related to MDD.

Visual cortex repetitive transcranial magnetic stimulation (rTMS) reversing neurodevelopmental impairments in adolescents with major psychiatric disorders (MPDs): A cross-species translational study

AIMS

Neurodevelopmental impairments are closely linked to the basis of adolescent major psychiatric disorders (MPDs). The visual cortex can regulate neuroplasticity throughout the brain during critical periods of neurodevelopment, which may provide a promising target for neuromodulation therapy. This cross-species translational study examined the effects of visual cortex repetitive transcranial magnetic stimulation (rTMS) on neurodevelopmental impairments in MPDs.

METHODS

Visual cortex rTMS was performed in both adolescent methylazoxymethanol acetate (MAM) rats and patients with MPDs. Functional magnetic resonance imaging (fMRI) and brain tissue proteomic data in rats and fMRI and clinical symptom data in patients were analyzed.

RESULTS

The regional homogeneity (ReHo) analysis of fMRI data revealed an increase in the frontal cortex and a decrease in the posterior cortex in the MAM rats, representing the abnormal neurodevelopmental pattern in MPDs. In regard to the effects of rTMS, similar neuroimaging changes, particularly reduced frontal ReHo, were found both in MAM rats and adolescent patients, suggesting that rTMS may reverse the abnormal neurodevelopmental pattern. Proteomic analysis revealed that rTMS modulated frontal synapse-associated proteins, which may be the underpinnings of rTMS efficacy. Furthermore, a positive relationship was observed between frontal ReHo and clinical symptoms after rTMS in patients.

CONCLUSION

Visual cortex rTMS was proven to be an effective treatment for adolescent MPDs, and the underlying neural and molecular mechanisms were uncovered. Our study provides translational evidence for therapeutics targeting the neurodevelopmental factor in MPDs.

Estimating the impact of transmitted and non-transmitted psychiatric and neurodevelopmental polygenic scores on youth emotional problems

Anxiety and depression (emotional disorders) are familial and heritable, especially when onset is early. However, other cross-generational studies suggest transmission of youth emotional problems is explained by mainly environmental risks. We set out to test the contribution of parental non-transmitted genetic liability, as indexed by psychiatric/neurodevelopmental common polygenic liability, to youth emotional problems using a UK population-based cohort: the Millennium Cohort Study. European (N = 6328) and South Asian (N = 814) ancestries were included, as well as a subset with genomic data from both parents (European: N = 2809; South Asian: N = 254). We examined the association of transmitted (PGST) and non-transmitted polygenic scores (PGSNT) for anxiety, depression, bipolar disorder and neurodevelopmental disorders (attention-deficit/hyperactivity disorder [ADHD], autism spectrum disorder [ASD], schizophrenia) with youth emotional disorder and symptom scores, measured using the parent- and self-reported Strengths and Difficulties Questionnaire emotional subscale at 6 timepoints between ages 3-17 years. In the European sample, PGST for anxiety and depression, but not bipolar disorder, were associated with emotional disorder and symptom scores across all ages, except age 3, with strongest association in adolescence. ADHD and ASD PGST also showed association across ages 11-17 years. In the South Asian sample, evidence for associations between all PGST and outcome measures were weaker. There was weak evidence of association between PGSNT for anxiety and depression and age 17 symptom scores in the South Asian sample, but not in the European sample for any outcome. Overall, PGST for depression, anxiety, ADHD and ASD contributed to youth emotional problems, with stronger associations in adolescence. There was limited support for non-transmitted genetic effects: these findings do not support the hypothesis that parental polygenic psychiatric/neurodevelopmental liability confer risk to offspring emotional problems through non-transmitted rearing/nurture effects.

Suicidal Thoughts and Trajectories of Psychopathological and Behavioral Symptoms in Adolescence

Importance

The suicidal risk of psychopathology in adolescence is suggested to differ based on its longitudinal trajectory, but the comorbidity of these symptom trajectories has not been well examined. This study comprehensively clustered trajectories of multiple psychopathological and behavioral symptoms and examined their associations with suicidal thoughts in adolescence.

Objective

To determine which categories and trajectories of psychopathological and behavioral symptoms are associated with suicidal thoughts in adolescence, accounting for comorbid symptoms.

Design, Setting, and Participants

This population-based cohort study in Japan used data from the Tokyo Teen Cohort (TTC) study, which was established in 2012 and is currently ongoing. Data from 3 waves of surveys conducted at ages 10, 12, and 16 years from October 2012 to September 2021 were used. Of the adolescents in the cohort, participants with at least 2 evaluations of psychopathological and behavioral symptoms were included. Data were analyzed from December 2022 to March 2023.

Exposure

Latent class growth analysis was used to cluster the trajectory of each psychopathological and behavioral symptom.

Main Outcomes and Measures

The associations between symptom trajectories and suicidal thoughts at age 16 were examined. Suicidal thoughts were assessed using a self-report questionnaire. Psychopathological and behavioral symptoms were assessed using the 8 subscale scores of the caregiver-report Child Behavior Checklist.

Results

This study included 2780 adolescents (1306 female participants [47.0%]). Of the 1920 adolescents with data on suicidal thoughts, 158 (8.2%) had suicidal thoughts. The median (IQR) age was 10.2 (10.0-10.3) years at the first evaluation, 11.9 (11.8-12.1) years at the second evaluation, and 16.3 (16.1-16.5) years at the last evaluation. The clustering pattern of trajectories varied depending on symptom categories. After adjusting for each symptom trajectory and confounders, adolescents with persistent high withdrawn symptoms (odds ratio [OR], 1.88; 95% CI, 1.10-3.21) and those with increasing somatic symptoms (OR, 1.97; 95% CI, 1.16-3.34) had a significantly higher risk of suicidal thoughts than adolescents without these symptoms. There was no interaction between these symptom trajectories and the risk of suicidal thoughts.

Conclusions and Relevance

This cohort study found that persistent withdrawn symptoms and increasing somatic symptoms during early to midadolescence were associated with an increased risk of suicidal thoughts in midadolescence, even after accounting for comorbid symptoms and confounders. Attention should be paid to the suicidal risk associated with these symptoms, particularly when they persist or increase in the longitudinal follow-up.

Individual Trajectories of Depressive Symptoms Within Racially-Ethnically Diverse Youth: Associations with Polygenic Risk for Depression and Substance Use Intent and Perceived Harm

There are distinct individual trajectories of depressive symptoms across adolescence which are most often differentiated into low, moderate/stable, and high/increasing groups. Research has found genetic predisposition for depression associated with trajectories characterized by greater depressive symptoms. However, the majority of this research has been conducted in White youth. Moreover, a separate literature indicates that trajectories with elevated depressive symptoms can result in substance use. It is critical to identify depressive symptom trajectories, genetic predictors, and substance use outcomes in diverse samples in early adolescence to understand distinct processes and convey equitable benefits from research. Using data from the Adolescent Cognitive Brain Development Study (ABCD), we examined parent-reported depressive symptom trajectories within Black/African American (AA, n = 1783), White/European American (EA, n = 6179), and Hispanic/Latinx (LX, n = 2410) youth across four annual assessments in early adolescence (age 9-10 to 12-13). We examined racially/ethnically aligned polygenic scores (Dep-PGS) as predictors of trajectories as well as substance use intent and perceived substance use harm as outcomes at age 12-13. Differential trajectories were found in AA, EA, and LX youth but low and high trajectories were represented within each group. In EA youth, greater Dep-PGS were broadly associated with membership in trajectories with greater depressive symptoms. Genetic effects were not significant in AA and LX youth. In AA youth, membership in the low trajectory was associated with greater substance use intent. In EA youth, membership in trajectories with higher depressive symptoms was associated with greater substance use intent and less perceived harm. There were no associations between trajectories and substance use intent and perceived harm in LX youth. These findings indicate that there are distinct depressive symptom trajectories in AA, EA, and LX youth, accompanied by unique associations with genetic predisposition for depressive symptoms and substance use outcomes.

Polygenic risk for depression and anterior and posterior hippocampal volume in children and adolescents

BACKGROUND

Depression has frequently been associated with smaller hippocampal volume. The hippocampus varies in function along its anterior-posterior axis, with the anterior hippocampus more strongly associated with stress and emotion processing. The goals of this study were to examine the associations among parental history of anxiety/depression, polygenic risk scores for depression (PGS-DEP), and anterior and posterior hippocampal volumes in children and adolescents. To examine specificity to PGS-DEP, we examined associations of educational attainment polygenic scores (PGS-EA) with anterior and posterior hippocampal volume.

METHODS

Participants were 350 3- to 21-year-olds (46 % female). PGS-DEP and PGS-EA were computed based on recent, large-scale genome-wide association studies. High-resolution, T1-weighted magnetic resonance imaging (MRI) data were acquired, and a semi-automated approach was used to segment the hippocampus into anterior and posterior subregions.

RESULTS

Children and adolescents with higher polygenic risk for depression were more likely to have a parent with a history of anxiety/depression. Higher polygenic risk for depression was significantly associated with smaller anterior but not posterior hippocampal volume. PGS-EA was not associated with anterior or posterior hippocampal volumes.

LIMITATIONS

Participants in these analyses were all of European ancestry.

CONCLUSIONS

Polygenic risk for depression may lead to smaller anterior but not posterior hippocampal volume in children and adolescents, and there may be specificity of these effects to PGS-DEP rather than PGS-EA. These findings may inform the earlier identification of those in need of support and the design of more effective, personalized treatment strategies.

DECLARATIONS OF INTEREST

none.

DECLARATIONS OF INTEREST

None.

Stratifying early-onset emotional disorders: using genetics to assess persistence in young people of European and South Asian ancestry

BACKGROUND

Depression and anxiety are the most common mental health problems in young people. Currently, clinicians are advised to wait before initiating treatment for young people with these disorders as many spontaneously remit. However, others develop recurrent disorder but this subgroup cannot be identified at the outset. We examined whether psychiatric polygenic scores (PGS) could help inform stratification efforts to predict those at higher risk of recurrence.

METHODS

Probable emotional disorder was examined in two UK population cohorts using the emotional symptoms subscale of the Strengths and Difficulties Questionnaire (SDQ). Those with emotional disorder at two or more time points between ages 5 and 25 years were classed as 'recurrent emotional disorder' (n = 1,643) and those with emotional disorder at one time point as having 'single episode emotional disorder' (n = 1,435, controls n = 8,715). We first examined the relationship between psychiatric PGS and emotional disorders in childhood and adolescence. Second, we tested whether psychiatric PGS added to predictor variables of known association with emotional disorder (neurodevelopmental comorbidity, special educational needs, family history of depression and socioeconomic status) when discriminating between single-episode and recurrent emotional disorder. Analyses were conducted separately in individuals of European and South Asian ancestry.

RESULTS

Probable emotional disorder was associated with higher PGS for major depressive disorder (MDD), anxiety, broad depression, ADHD and autism spectrum disorder (ASD) in those of European ancestry. Higher MDD and broad depression PGS were associated with emotional disorder in people of South Asian ancestry. Recurrent, compared to single-episode, emotional disorder was associated with ASD and parental psychiatric history. PGS were not associated with episode recurrence, and PGS did not improve discrimination of recurrence when combined with clinical predictors.

CONCLUSIONS

Our findings do not support the use of PGS as a tool to assess the likelihood of recurrence in young people experiencing their first episode of emotional disorder.

Networks of Neurodevelopmental Traits, Socioenvironmental Factors, Emotional Dysregulation in Childhood, and Depressive Symptoms Across Development in Two U.K. Cohorts

OBJECTIVE

Previous population-based studies have identified associations between childhood neurodevelopmental traits and depression in childhood, adolescence, and young adulthood. However, neurodevelopmental traits are highly correlated with each other, which could confound associations when traits are examined in isolation. The authors sought to identify unique associations between multiple neurodevelopmental traits in childhood and depressive symptoms across development, while taking into account co-occurring difficulties, in multivariate analyses.

METHODS

Data from two U.K. population-based cohorts, the Twins Early Development Study (TEDS) (N=4,407 independent twins) and the Avon Longitudinal Study of Parents and Children (ALSPAC) (N=10,351), were independently analyzed. Bayesian Gaussian graphical models were estimated to investigate pairwise conditional associations between neurodevelopmental traits (autism and ADHD symptoms and general cognitive, learning, and communication abilities), socioenvironmental stressors (academic performance and peer relations), and emotional dysregulation in childhood (ages 7-11) and depressive symptoms across development (ages 12, 16, and 21).

RESULTS

In both cohorts, bivariate correlations indicated several associations between neurodevelopmental traits and depressive symptoms across development. However, based on replicated findings across cohorts, these pairs of variables were mostly conditionally independent, and none were conditionally associated, after accounting for socioenvironmental stressors and emotional dysregulation. In turn, socioenvironmental stressors and emotional dysregulation were conditionally associated with both neurodevelopmental traits and depressive symptoms. Based on replicated findings across cohorts, neurodevelopmental traits in childhood could be associated only indirectly with depressive symptoms across development.

CONCLUSIONS

This study indicates that associations between childhood neurodevelopmental traits and depressive symptoms across development could be explained by socioenvironmental stressors and emotional dysregulation. The present findings could inform future research aimed at the prevention of depression in youths with neurodevelopmental disorders.

Characterising depression trajectories in young people at high familial risk of depression

BACKGROUND

Parental depression is a common and potent risk factor for depression in offspring. However, the developmental course of depression from childhood to early-adulthood has not been characterized in this high-risk group.

METHODS

Using longitudinal data from 337 young people who had a parent with a history of recurrent major depressive disorder (MDD), we characterized trajectories of broadly defined depressive disorder using latent class growth analysis. We used clinical descriptions to further characterise trajectory classes.

RESULTS

Two trajectory classes were identified: childhood-emerging (25 %) and adulthood-emerging (75 %). The childhood-emerging class showed high rates of depressive disorder from age 12.5, which persisted through the study period. The adulthood-emerging class showed low rates of depressive disorder until age 26. Individual factors (IQ and ADHD symptoms) and parent depression severity (comorbidity, persistence and impairment) differentiated the classes but there were no differences in family history score or polygenic scores associated with psychiatric disorder. Clinical descriptions indicated functional impairment in both classes, but more severe symptomatology and impairment in the childhood-emerging class.

LIMITATIONS

Attrition particularly affected participation in young adulthood. Factors associated with attrition were low family income, single parent household status and low parental education.

CONCLUSIONS

The developmental course of depressive disorder in children of depressed parents is variable. When followed up to adult life, most individuals exhibited some functional impairment. An earlier age-of-onset was associated with a more persistent and impairing course of depression. Access to effective prevention strategies is particularly warranted for at-risk young people showing early-onsetting and persistent depressive symptoms.

Genetic patterning for child psychopathology is distinct from that for adults and implicates fetal cerebellar development

Childhood psychiatric symptoms are often diffuse but can coalesce into discrete mental illnesses during late adolescence. We leveraged polygenic scores (PGSs) to parse genomic risk for childhood symptoms and to uncover related neurodevelopmental mechanisms with transcriptomic and neuroimaging data. In independent samples (Adolescent Brain Cognitive Development, Generation R) a narrow cross-disorder neurodevelopmental PGS, reflecting risk for attention deficit hyperactivity disorder, autism, depression and Tourette syndrome, predicted psychiatric symptoms through early adolescence with greater sensitivity than broad cross-disorder PGSs reflecting shared risk across eight psychiatric disorders, the disorder-specific PGS individually or two other narrow cross-disorder (Compulsive, Mood-Psychotic) scores. Neurodevelopmental PGS-associated genes were preferentially expressed in the cerebellum, where their expression peaked prenatally. Further, lower gray matter volumes in cerebellum and functionally coupled cortical regions associated with psychiatric symptoms in mid-childhood. These findings demonstrate that the genetic underpinnings of pediatric psychiatric symptoms differ from those of adult illness, and implicate fetal cerebellar developmental processes that endure through childhood.

General v. specific vulnerabilities: polygenic risk scores and higher-order psychopathology dimensions in the Adolescent Brain Cognitive Development (ABCD) Study

BACKGROUND

Polygenic risk scores (PRSs) capture genetic vulnerability to psychiatric conditions. However, PRSs are often associated with multiple mental health problems in children, complicating their use in research and clinical practice. The current study is the first to systematically test which PRSs associate broadly with all forms of childhood psychopathology, and which PRSs are more specific to one or a handful of forms of psychopathology.

METHODS

The sample consisted of 4717 unrelated children (mean age = 9.92, s.d. = 0.62; 47.1% female; all European ancestry). Psychopathology was conceptualized hierarchically as empirically derived general factor (p-factor) and five specific factors: externalizing, internalizing, neurodevelopmental, somatoform, and detachment. Partial correlations explored associations between psychopathology factors and 22 psychopathology-related PRSs. Regressions tested which level of the psychopathology hierarchy was most strongly associated with each PRS.

RESULTS

Thirteen PRSs were significantly associated with the general factor, most prominently Chronic Multisite Pain-PRS (r = 0.098), ADHD-PRS (r = 0.079), and Depression-PRS (r = 0.078). After adjusting for the general factor, Depression-PRS, Neuroticism-PRS, PTSD-PRS, Insomnia-PRS, Chronic Back Pain-PRS, and Autism-PRS were not associated with lower order factors. Conversely, several externalizing PRSs, including Adventurousness-PRS and Disinhibition-PRS, remained associated with the externalizing factor (|r| = 0.040-0.058). The ADHD-PRS remained uniquely associated with the neurodevelopmental factor (r = 062).

CONCLUSIONS

PRSs developed to predict vulnerability to emotional difficulties and chronic pain generally captured genetic risk for all forms of childhood psychopathology. PRSs developed to predict vulnerability to externalizing difficulties, e.g. disinhibition, tended to be more specific in predicting behavioral problems. The results may inform translation of existing PRSs to pediatric research and future clinical practice.

Emotional problems in preschool and school-aged children with neurodevelopmental disorders in Spain: EPINED epidemiological project

BACKGROUND

Children with neurodevelopmental disorders (NDD) are often at risk of developing emotional problems.

AIMS AND METHODS

The co-occurrence of anxiety and depression with ASD and/or ADHD was determined by exploring the association with children's clinical and neuropsychological functioning and their parent's mental health. To this end, we assessed 295 preschoolers (PRE; 4-5 years old) and 486 school-aged children (SCH; 10-11 years old) in Tarragona, Spain. NDD diagnoses were based on DSM-5. Emotional problems were assessed using Achenbach's scales.

RESULTS

Emotional problems (PRE: 36%-78%; SCH: 32%-81%) were more common and more severe in participants with NDD than in controls and children in the ASD + ADHD school-aged group were the most affected. In ADHD, emotional problems were associated with more severe symptoms of attention deficit (PRE) and hyperactivity/impulsivity (SCH). In ASD + ADHD, emotional problems showed a trend of association with more severe ASD repetitive behaviours and impaired working memory, whereas in ASD were associated with greater overall ASD severity.

CONCLUSIONS AND IMPLICATIONS

Children with NDD are vulnerable to emotional problems, which become more prevalent and interfering with age. Early detection and intervention aimed at tackling emotional problems can improve NDD prognosis.

Polygenic risk associations with developmental and mental health outcomes in childhood and adolescence: A systematic review

Background

Neurodevelopmental and mental health disorders in childhood constitute an emerging global concern, with adverse sequelae which span children's physical, psychological and social well-being. The aetiology of these disorders is likely complex, multifactorial and polygenic. Polygenic risk scores (PRS), an estimate of an individual's genetic liability toward a disorder, have been increasingly used in psychiatric research to explore genetic associations with disorders of interest. However, limited work delineates polygenic associations with development and mental health in childhood populations.We aimed to systematically review existing literature on associations between genetic risk (as measured by PRS) and neurodevelopmental and mental health outcomes in childhood and adolescence.

Methods

Following the recommended Preferred Reporting Items for Meta-Analyses (PRISMA) guidelines, databases were searched using key search terms. The search commenced in March 2021 and concluded in June 2021. The studies eligible for inclusion were full-text articles investigating polygenic risk associations with neurodevelopmental and/or mental health outcomes in childhood or adolescence.

Results

Fourteen studies were eligible for inclusion in this systematic review. The association between higher PRS for attention-deficit/hyperactivity disorder (ADHD) and adverse developmental/mental health outcomes in childhood and adolescence was reported by five studies. Additionally, associations between PRS for bipolar disorder or major depressive disorder and adverse outcomes of interest were also described by two studies; and two studies highlighted associations between schizophrenia PRS and mental health disorders in childhood. The remaining studies highlighted shared polygenic contributions between and within NDDs and mental health disorders in children.

Conclusion

The findings of this systematic review suggest that PRS for neurodevelopmental and mental health disorders may associate with adverse neurodevelopmental and mental health outcomes from early childhood to adolescence. In addition, these associations seemed not to be phenotype-specific, suggesting potential shared genetic variation across the phenotypes of interest.

Progressive Voxel-Wise Homotopic Connectivity from childhood to adulthood: Age-related functional asymmetry in resting-state functional magnetic resonance imaging

Homotopic connectivity during resting state has been proposed as a risk marker for neurologic and psychiatric conditions, but a precise characterization of its trajectory through development is currently lacking. Voxel-Mirrored Homotopic Connectivity (VMHC) was evaluated in a sample of 85 neurotypical individuals aged 7-18 years. VMHC associations with age, handedness, sex, and motion were explored at the voxel-wise level. VMHC correlates were also explored within 14 functional networks. Primary and secondary outcomes were repeated in a sample of 107 adults aged 21-50 years. In adults, VMHC was negatively correlated with age only in the posterior insula (false discovery rate p < .05, >30-voxel clusters), while a distributed effect among the medial axis was observed in minors. Four out of 14 considered networks showed significant negative correlations between VMHC and age in minors (basal ganglia r = -.280, p = .010; anterior salience r = -.245, p = .024; language r = -.222, p = .041; primary visual r = -.257, p = .017), but not adults. In minors, a positive effect of motion on VMHC was observed only in the putamen. Sex did not significantly influence age effects on VMHC. The current study showed a specific decrease in VMHC for minors as a function of age, but not adults, supporting the notion that interhemispheric interactions can shape late neurodevelopment.

New insights from the last decade of research in psychiatric genetics: discoveries, challenges and clinical implications

Psychiatric genetics has made substantial progress in the last decade, providing new insights into the genetic etiology of psychiatric disorders, and paving the way for precision psychiatry, in which individual genetic profiles may be used to personalize risk assessment and inform clinical decision-making. Long recognized to be heritable, recent evidence shows that psychiatric disorders are influenced by thousands of genetic variants acting together. Most of these variants are commonly occurring, meaning that every individual has a genetic risk to each psychiatric disorder, from low to high. A series of large-scale genetic studies have discovered an increasing number of common and rare genetic variants robustly associated with major psychiatric disorders. The most convincing biological interpretation of the genetic findings implicates altered synaptic function in autism spectrum disorder and schizophrenia. However, the mechanistic understanding is still incomplete. In line with their extensive clinical and epidemiological overlap, psychiatric disorders appear to exist on genetic continua and share a large degree of genetic risk with one another. This provides further support to the notion that current psychiatric diagnoses do not represent distinct pathogenic entities, which may inform ongoing attempts to reconceptualize psychiatric nosology. Psychiatric disorders also share genetic influences with a range of behavioral and somatic traits and diseases, including brain structures, cognitive function, immunological phenotypes and cardiovascular disease, suggesting shared genetic etiology of potential clinical importance. Current polygenic risk score tools, which predict individual genetic susceptibility to illness, do not yet provide clinically actionable information. However, their precision is likely to improve in the coming years, and they may eventually become part of clinical practice, stressing the need to educate clinicians and patients about their potential use and misuse. This review discusses key recent insights from psychiatric genetics and their possible clinical applications, and suggests future directions.

Attention-deficit/hyperactivity disorder and other neurodevelopmental disorders in offspring of parents with depression and bipolar disorder

BACKGROUND

Offspring of parents with major mood disorders (MDDs) are at increased risk for early psychopathology. We aim to compare the rates of neurodevelopmental disorders in offspring of parents with bipolar disorder, major depressive disorder, and controls.

METHOD

We established a lifetime diagnosis of neurodevelopmental disorders [attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, communication disorders, intellectual disabilities, specific learning disorders, and motor disorders] using the Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime Version in 400 participants (mean age 11.3 + s.d. 3.9 years), including 93 offspring of parents with bipolar disorder, 182 offspring of parents with major depressive disorder, and 125 control offspring of parents with no mood disorder.

RESULTS

Neurodevelopmental disorders were elevated in offspring of parents with bipolar disorder [odds ratio (OR) 2.34, 95% confidence interval (CI) 1.23-4.47, p = 0.010] and major depressive disorder (OR 1.87, 95% CI 1.03-3.39, p = 0.035) compared to controls. This difference was driven by the rates of ADHD, which were highest among offspring of parents with bipolar disorder (30.1%), intermediate in offspring of parents with major depressive disorder (24.2%), and lowest in controls (14.4%). There were no significant differences in frequencies of other neurodevelopmental disorders between the three groups. Chronic course of mood disorder in parents was associated with higher rates of any neurodevelopmental disorder and higher rates of ADHD in offspring.

CONCLUSIONS

Our findings suggest monitoring for ADHD and other neurodevelopmental disorders in offspring of parents with MDDs may be indicated to improve early diagnosis and treatment.

Practitioner Review: Attention-deficit hyperactivity disorder and autism spectrum disorder - the importance of depression

Young people with neurodevelopmental disorders, such as attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), show high rates of mental health problems, of which depression is one of the most common. Given that depression in ASD and ADHD is linked with a range of poor outcomes, knowledge of how clinicians should assess, identify and treat depression in the context of these neurodevelopmental disorders is much needed. Here, we give an overview of the latest research on depression in young people with ADHD and ASD, including possible mechanisms underlying the link between ADHD/ASD and depression, as well as the presentation, assessment and treatment of depression in these neurodevelopmental disorders. We discuss the implications for clinicians and make recommendations for critical future research in this area.

Age of onset for major depressive disorder and its association with symptomatology

BACKGROUND

The age of onset (AOO) is a key factor for heterogeneity in major depressive disorder (MDD). Looking at the effect of AOO on symptomatology may improve clinical outcomes. This study aims to examine whether and how AOO affects symptomatology using a machine learning approach and latent profile analysis (LPA).

METHODS

The study enrolled 915 participants diagnosed with MDD from eight hospitals across China. Depressive symptoms were assessed using the 17-item Hamilton Depression Rating Scale. The relationship between symptom profiles and AOO was explored using Random Forest. The effect of AOO on symptom clusters and subtypes was investigated using multiple linear regression and LPA. A continuous AOO indicator was used to conduct the analyses.

RESULTS

Based on the Random Forest, symptom profiles were closely associated with AOO. The regression model showed that the severity of neurovegetative symptoms was positively associated with AOO (β = 0.18, p < 0.001), and the severity of cognitive-behavioral symptoms was negatively associated with AOO (β = -0.12, p < 0.001). LPA demonstrated that the subgroups characterized by suicide and guilt had earlier onset of depression. The subgroup with the lowest global severity of depression had the latest onset.

LIMITATIONS

AOO was recalled retrospectively. The relative scarcity of participants with childhood and adolescence onset depression.

CONCLUSIONS

AOO has an important impact on symptomatology. The findings may enhance clinical evaluations for MDD and assist clinicians in promoting earlier detection and individualized care in vulnerable individuals.

Using genetic designs to identify likely causal environmental contributions to psychopathology

The multifactorial nature of psychopathology, whereby both genetic and environmental factors contribute risk, has long been established. In this paper, we provide an update on genetically informative designs that are utilized to disentangle genetic and environmental contributions to psychopathology. We provide a brief reminder of quantitative behavioral genetic research designs that have been used to identify potentially causal environmental processes, accounting for genetic contributions. We also provide an overview of recent molecular genetic approaches that utilize genome-wide association study data which are increasingly being applied to questions relevant to psychopathology research. While genetically informative designs typically have been applied to investigate the origins of psychopathology, we highlight how these approaches can also be used to elucidate potential causal environmental processes that contribute to developmental course and outcomes. We highlight the need to use genetically sensitive designs that align with intervention and prevention science efforts, by considering strengths-based environments to investigate how positive environments can mitigate risk and promote children's strengths.

Depression in young people

Depression rates in young people have risen sharply in the past decade, especially in females, which is of concern because adolescence is a period of rapid social, emotional, and cognitive development and key life transitions. Adverse outcomes associated with depression in young people include depression recurrence; the onset of other psychiatric disorders; and wider, protracted impairments in interpersonal, social, educational, and occupational functioning. Thus, prevention and early intervention for depression in young people are priorities. Preventive and early intervention strategies typically target predisposing factors, antecedents, and symptoms of depression. Young people who have a family history of depression, exposure to social stressors (eg, bullying, discordant relationships, or stressful life events), and belong to certain subgroups (eg, having a chronic physical health problem or being a sexual minority) are at especially high risk of depression. Clinical antecedents include depressive symptoms, anxiety, and irritability. Evidence favours indicated prevention and targeted prevention to universal prevention. Emerging school-based and community-based social interventions show some promise. Depression is highly heterogeneous; therefore, a stepwise treatment approach is recommended, starting with brief psychosocial interventions, then a specific psychological therapy, and then an antidepressant medication.

First-Episode Psychosis Patients Who Deteriorated in the Premorbid Period Do Not Have Higher Polygenic Risk Scores Than Others: A Cluster Analysis of EU-GEI Data

Cluster studies identified a subgroup of patients with psychosis whose premorbid adjustment deteriorates before the onset, which may reflect variation in genetic influence. However, other studies reported a complex relationship between distinctive patterns of cannabis use and cognitive and premorbid impairment that is worthy of consideration. We examined whether: (1) premorbid social functioning (PSF) and premorbid academic functioning (PAF) in childhood and adolescence and current intellectual quotient (IQ) define different clusters in 802 first-episode of psychosis (FEP) patients; resulting clusters vary in (2) polygenic risk scores (PRSs) for schizophrenia (SCZ_PRS), bipolar disorder (BD_PRS), major depression (MD_PRS), and IQ (IQ_PRS), and (3) patterns of cannabis use, compared to 1,263 population-based controls. Four transdiagnostic clusters emerged (BIC = 2268.5): (1) high-cognitive-functioning (n = 205), with the highest IQ (Mean = 106.1, 95% CI: 104.3, 107.9) and PAF, but low PSF. (2) Low-cognitive-functioning (n = 223), with the lowest IQ (Mean = 73.9, 95% CI: 72.2, 75.7) and PAF, but normal PSF. (3) Intermediate (n = 224) (Mean_IQ = 80.8, 95% CI: 79.1, 82.5) with low-improving PAF and PSF. 4) Deteriorating (n = 150) (Mean_IQ = 80.6, 95% CI: 78.5, 82.7), with normal-deteriorating PAF and PSF. The PRSs explained 7.9% of between-group membership. FEP had higher SCZ_PRS than controls [F(4,1319) = 20.4, P < .001]. Among the clusters, the deteriorating group had lower SCZ_PRS and was likelier to have used high-potency cannabis daily. Patients with FEP clustered according to their premorbid and cognitive abilities. Pronounced premorbid deterioration was not typical of most FEP, including those more strongly predisposed to schizophrenia, but appeared in a cluster with a history of high-potency cannabis use.

The Australian Genetics of Depression Study: New Risk Loci and Dissecting Heterogeneity Between Subtypes

BACKGROUND

Major depressive disorder (MDD) is a common and highly heterogeneous psychiatric disorder, but little is known about the genetic characterization of this heterogeneity. Understanding the genetic etiology of MDD can be challenging because large sample sizes are needed for gene discovery-often achieved with a trade-off in the depth of phenotyping.

METHODS

The Australian Genetics of Depression Study is the largest stand-alone depression cohort with both genetic data and in-depth phenotyping and comprises a total of 15,792 participants of European ancestry, 92% of whom met diagnostic criteria for MDD. We leveraged the unique nature of this cohort to conduct a meta-analysis with the largest publicly available depression genome-wide association study to date and subsequently used polygenic scores to investigate genetic heterogeneity across various clinical subtypes of MDD.

RESULTS

We increased the number of known genome-wide significant variants associated with depression from 103 to 126 and found evidence of association of novel genes implicated in neuronal development. We found that a polygenic score for depression explained 5.7% of variance in MDD liability in our sample. Finally, we found strong support for genetic heterogeneity in depression with differential associations of multiple psychiatric and comorbid traits with age of onset, longitudinal course, and various subtypes of MDD.

CONCLUSIONS

Until now, this degree of detailed phenotyping in such a large sample of MDD cases has not been possible. Along with the discovery of novel loci, we provide support for differential pathways to illness models that recognize the overlap with other common psychiatric disorders as well as pathophysiological differences.

Polygenic risks for joint developmental trajectories of internalizing and externalizing problems: findings from the ALSPAC cohort

BACKGROUND

Joint developmental trajectories of internalizing and externalizing problems show considerable heterogeneity; however, this can be parsed into a small number of meaningful subgroups. Doing so offered insights into risk factors that lead to different patterns of internalizing/externalizing trajectories. However, despite both domains of problems showing strong heritability, no study has yet considered genetic risks as predictors of joint internalizing/externalizing problem trajectories.

METHODS

Using parallel process latent class growth analysis, we estimated joint developmental trajectories of internalizing and externalizing difficulties assessed across ages 4 to 16 using the Strengths and Difficulties Questionnaire. Multinomial logistic regression was used to evaluate a range of demographic, perinatal, maternal mental health, and child and maternal polygenic predictors of group membership. Participants included 11,049 children taking part in the Avon Longitudinal Study of Parents and Children. Polygenic data were available for 7,127 children and 6,836 mothers.

RESULTS

A 5-class model was judged optimal: Unaffected, Moderate Externalizing Symptoms, High Externalizing Symptoms, Moderate Internalizing and Externalizing Symptoms and High Internalizing and Externalizing Symptoms. Male sex, lower maternal age, maternal mental health problems, maternal smoking during pregnancy, higher child polygenic risk scores for ADHD and lower polygenic scores for IQ distinguished affected classes from the unaffected class.

CONCLUSIONS

While affected classes could be relatively well separated from the unaffected class, phenotypic and polygenic predictors were limited in their ability to distinguish between different affected classes. Results thus add to existing evidence that internalizing and externalizing problems have mostly shared risk factors.

Causal Effect of Age at Menarche on the Risk for Depression: Results From a Two-Sample Multivariable Mendelian Randomization Study

A fair number of epidemiological studies suggest that age at menarche (AAM) is associated with depression, but the reported effect sizes are small, and there is evidence of residual confounding. Moreover, previous Mendelian randomization (MR) studies to avoid inferential problems inherent to epidemiological studies have provided mixed findings. To clarify the causal relationship between age at menarche and broadly defined depression risk, we used 360 genome-wide significantly AAM-related single-nucleotide polymorphisms (SNPs) as instrumental variable and data from the latest GWAS for the broadly defined depression risk on 807,553 individuals (246,363 cases and 561,190 controls). Multiple methods to account for heterogeneity of the instrumental variable (penalized weighted median, MR Lasso, and contamination mixture method), systematic and idiosyncratic pleiotropy (MR RAPS), and horizontal pleiotropy (MR PRESSO and multivariable MR using three methods) were used. Body mass index, education attainment, and total white blood count were considered pleiotropic phenotypes in the multivariable MR analysis. In the univariable [inverse-variance weighted (IVW): OR = 0.96, 95% confidence interval = 0.94–0.98, p = 0.0003] and multivariable MR analysis (IVW: OR = 0.96, 95% confidence interval = 0.94–0.99, p = 0.007), there was a significant causal effect of AAM on depression risk. Thus, the present study supports conclusions from previous epidemiological studies implicating AAM in depression without the pitfalls of residual confounding and reverse causation. Considering the adverse consequences of an earlier AAM on mental health, this finding should foster efforts to address risk factors that promote an earlier AAM.

Childhood-onset versus adolescent-onset anxiety and depression: Epidemiological and neurodevelopmental aspects

Anxiety and depression are common in youth and are frequently accompanied by attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). However, it is unclear how common ADHD, ASD, and other neurodevelopmental disorders (NDDs, i.e., ADHD, ASD, developmental coordination disorder, learning disorder, and tic disorders) are in children versus adolescents with anxiety and depression. We aimed to delineate whether different anxiety/depression age-of-onset groups show distinguishable NDD patterns. The study was based on 4492 twins born in Sweden between 1998 and 2003 from the nation-wide population-based Child and Adolescent Twin Study in Sweden. Prevalence and odds ratios were calculated using screening measures of anxiety and depression at ages 9 and 15, and NDDs at age 9. Individuals with childhood-onset anxiety/depression had a substantially higher NDD prevalence compared to individuals with adolescent-onset anxiety/depression. Highest prevalence was found for individuals with anxiety/depression both in childhood and adolescence. In this group, individuals also had substantially higher odds of having at least one NDD (14.7, 95% CI 6.3 - 34.0) compared to individuals without anxiety/depression. This emphasizes the need to further investigate the etiology of childhood and adolescent anxiety/depression, as they most likely represent different constructs depending on age-of-onset, lending support for possibly different treatment approaches.

Antidepressants in children and adolescents with major depressive disorder and the influence of placebo response: A meta-analysis

BACKGROUND

There are few available antidepressants for pediatric Major Depressive Disorder (MDD). The objective of this systematic review and meta-analysis was to review industry-funded studies of antidepressants in children and adolescents with MDD, and to better understand the contribution of study design and placebo response to the findings of these studies.

METHODS

Randomized, double-blind, placebo-controlled clinical trials that compared antidepressant with placebo for the acute treatment of MDD in children and/or adolescents were selected. Estimates of the standardized mean difference (SMD) in change in Children's Depression Rating Scale-Revised scores were pooled, after examining for heterogeneity. A random-effects meta-analysis was completed.

RESULTS

Thirty-four antidepressant-placebo comparisons, involving 6161 subjects, were included. The SMD among all studies was 0.12 (CI 0.08, 0.17; p < 0.001), a very small effect size, lower than that seen in studies of adults with MDD. When the meta-analysis was limited to studies with a low mean placebo response, the SMD increased to 0.19 and further increased to 0.22 when studies with at least a 50% chance of receiving placebo were included.

LIMITATIONS

Many studies focused on older children and younger adolescents. Our findings may not reflect antidepressant efficacy in older adolescents.

CONCLUSIONS

The modest SMD identified in this analysis may reflect study design factors and the application of antidepressants developed for adults to pediatric patients. Given the urgent clinical need for more pediatric MDD treatments, the influence of placebo response and the need for drug development tailored to this population should be considered in pediatric MDD trial design.

Environmental factors in offspring of parents with mood disorders and their role in parent-child transmission: findings from a 14-year prospective high-risk study

Background

The factors involved in the transmission of mood disorders are only partially elucidated. Aside from genes, the family environment might play a crucial role in parent–child transmission. Our goals were to (1) assess the associations of parental bipolar disorder (BPD) and Major Depressive Disorder (MDD) with individual or shared family environmental factors, including traumatic events in offspring, parental separation, family cohesion and parental attitudes; and 2) test whether these factors were mediators of the association between exposure to parental mood disorders and the onset of these disorders in offspring.

Methods

The sample stems from an ongoing family high-risk study of mood disorders conducted in the French-speaking part of Switzerland. Given the strong impact of the age of onset of parental disorders on their transmission to children, parental disorders were dichotomized according to the onset (cut-off 21 years). Probands with early-onset (n = 30) and later-onset BPD (n = 51), early-onset (n = 21) and later-onset MDD (n = 47) and controls (n = 65), along with their spouses (n = 193) and offspring (n = 388; < 18 years on study inclusion), were assessed over a mean follow-up duration of 14 years (s.d: 4.6). The environmental measures were based on reports by offspring collected before the onset of their first mood episode.

Results

Offspring of probands with later-onset BPD and offspring of probands with both early-onset and later-onset MDD reported traumatic events more frequently than comparison offspring, whereas exposure to parental separation was more frequent in all groups of high-risk offspring. Moreover, several familial environment scores including parenting attitudes differed between offspring of probands with BPD and comparison offspring. However, none of these factors were mediators of the parent–child transmission of BPD. Among the environmental factors, traumatic events were shown to be modest mediators of the transmission of early-onset MDD.

Conclusions

Our data do not support the implication of the assessed environmental factors in the parent–child transmission of BPD. In contrast to BPD, traumatic events partially mediate the parent–child transmission of early-onset MDD, which has important implications for intervention and prevention. Early therapeutic efforts in offspring exposed to these events are likely to reduce their deleterious impact on the risk of subsequent MDD.

Internalizing symptoms in adolescence are modestly affected by symptoms of anxiety, depression, and neurodevelopmental disorders in childhood

BACKGROUND

Internalizing disorders, such as anxiety and depressive disorders, are common mental disorders in young people, but a detailed understanding of the symptom continuity from childhood to adolescence that additionally includes a variety of neurodevelopmental disorder (NDD) symptoms is lacking. We therefore aimed to assess the extent to which parent-reported anxiety, depression, and NDD symptoms in childhood predict parent-reported internalizing symptoms in adolescence.

METHODS

We used the nation-wide population-based Child and Adolescent Twin Study in Sweden, comprising 4492 twins born in Sweden between 1998 and 2003 that were assessed at age 9, and then again at age 15. Linear regression in a structural equation modelling framework was used to analyze the data.

RESULTS

Overall, our results indicate that 15.9% of the variance in internalizing symptoms at age 15 can be predicted by anxiety, depression, and NDD symptoms at age 9. Anxiety and NDD symptoms in childhood predicted the largest amount of internalizing symptoms in adolescence.

CONCLUSIONS

Adolescent internalizing symptoms are modestly affected by childhood symptoms of anxiety, depression, and NDDs, suggesting that they may represent different constructs across age. Future studies should further empirically investigate differences in etiology and trajectories of childhood versus adolescent internalizing symptoms.

Multi-Omics Characterization of Early- and Adult-Onset Major Depressive Disorder

Age at depressive onset (AAO) corresponds to unique symptomatology and clinical outcomes. Integration of genome-wide association study (GWAS) results with additional “omic” measures to evaluate AAO has not been reported and may reveal novel markers of susceptibility and/or resistance to major depressive disorder (MDD). To address this gap, we integrated genomics with metabolomics using data-driven network analysis to characterize and differentiate MDD based on AAO. This study first performed two GWAS for AAO as a continuous trait in (a) 486 adults from the Pharmacogenomic Research Network-Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS), and (b) 295 adults from the Combining Medications to Enhance Depression Outcomes (CO-MED) study. Variants from top signals were integrated with 153 p180-assayed metabolites to establish multi-omics network characterizations of early (<age 18) and adult-onset depression. The most significant variant (p = 8.77 × 10−8) localized to an intron of SAMD3. In silico functional annotation of top signals (p < 1 × 10−5) demonstrated gene expression enrichment in the brain and during embryonic development. Network analysis identified differential associations between four variants (in/near INTU, FAT1, CNTN6, and TM9SF2) and plasma metabolites (phosphatidylcholines, carnitines, biogenic amines, and amino acids) in early- compared with adult-onset MDD. Multi-omics integration identified differential biosignatures of early- and adult-onset MDD. These biosignatures call for future studies to follow participants from childhood through adulthood and collect repeated -omics and neuroimaging measures to validate and deeply characterize the biomarkers of susceptibility and/or resistance to MDD development.

Association between early-onset affective disorders and hypothyroidism in a larger number of psychiatric drug-free patients

AIMS

We aimed to assess the association between early onset of affective disorders and hypothyroidism in a larger number of psychiatric drug-free patients with bipolar disorder (BD) or major depressive disorder (MDD).

METHODS

Early onset of affective disorders was defined as BD and MDD developed before the age of 22 years. The hypothyroidism hierarchy were diagnosed biochemically and included subclinical and overt hypothyroidism in this study. Demographic and clinical data including diagnosis, illness duration and thyroid function parameters (TSH, T4, FT4, T3 and FT3) at admission were collected from patients' records. Adjusted odds ratio (OR) and 95% confidence interval (CI), which were estimated by logistic regression model, were used to assess the association between early-onset affective disorder and hypothyroidism.

RESULTS

The prevalence of hypothyroidism in early-onset affective disorders was higher than that in late-onset patients (in BD, 9.4% vs. 6.2%, χ² = 6.020, P = 0.014; and in MDD 12.7% vs. 6.6%, χ² = 13.295, P < 0.001). Early-onset affective disorders were 2.097 times (95% CI: 1.409-3.123) more likely to have hypothyroidism compared with late-onset patients, after adjustment for age, gender, duration of illness and mood episode (adjusted OR: 1.965, 95% CI: 1.198-3.221 in BD, and adjusted OR: 2.831, 95% CI: 1.378-5.817 in MDD, respectively).

LIMITATION

Because of the cross-sectional design of this study, we were unable to sort out causality between early-onset affective disorders and hypothyroidism.

CONCLUSION

Early-onset affective disorder may be associated with higher prevalence of hypothyroidism.

Systematic Review: Molecular Studies of Common Genetic Variation in Child and Adolescent Psychiatric Disorders

OBJECTIVE

A systematic review of studies using molecular genetics and statistical approaches to investigate the role of common genetic variation in the development, persistence, and comorbidity of childhood psychiatric traits was conducted.

METHOD

A literature review was performed using the PubMed database, following PRISMA guidelines. There were 131 studies meeting inclusion criteria, having investigated at least one type of childhood-onset or childhood-measured psychiatric disorder or trait with the aim of identifying trait-associated common genetic variants, estimating the contribution of single nucleotide polymorphisms (SNPs) to the amount of variance explained (SNP-based heritability), investigating genetic overlap between psychiatric traits, or investigating whether the stability in traits or the association with adult traits is explained by genetic factors.

RESULTS

The first robustly associated genetic variants have started to be identified for childhood psychiatric traits. There were substantial contributions of common genetic variants to many traits, with variation in single nucleotide polymorphism heritability estimates depending on age and raters. Moreover, genetic variants also appeared to explain comorbidity as well as stability across a range of psychiatric traits in childhood and across the life span.

CONCLUSION

Common genetic variation plays a substantial role in childhood psychiatric traits. Increased sample sizes will lead to increased power to identify genetic variants and to understand genetic architecture, which will ultimately be beneficial to targeted and prevention strategies. This can be achieved by harmonizing phenotype measurements, as is already proposed by large international consortia and by including the collection of genetic material in every study.

Adolescent depression and adult labor market marginalization: a longitudinal cohort study

Adolescent depression is linked to adult ill-health and functional impairment, but recent research suggests that individual/contextual factors might account for this association. This study aimed to test whether the clinical heterogeneity of adolescent depression is related to marginalization from the labor market across early to middle adulthood. Data were drawn from the Uppsala Longitudinal Adolescent Depression Study, a community-based cohort initially assessed with structured clinical interviews at age 16-17. The cohort (n = 321 depressed; n = 218 nondepressed) was followed up after 2+ decades through linkage to nationwide population-based registries. Outcomes included consecutive annual data on unemployment, work disability, social welfare recipiency, and a composite marginalization measure, spanning from age 21 to 40. Longitudinal associations were examined using logistic regression analysis in a generalized estimating equations modeling framework. Subsequent depressive episodes and educational attainment in early adulthood were explored as potential pathways. The results showed that adolescent depression was associated with adult marginalization outcomes, but the strength of association varied across depressed subgroups. Adolescents with persistent depressive disorder had higher odds of all outcomes, including the composite marginalization measure (adjusted OR = 2.0, 95% CI = 1.4-2.7, p < 0.001), and this was partially (31%) mediated by subsequent depressive episodes in early adulthood. Exploratory moderation analysis revealed that entry into tertiary education mitigated the association with later marginalization, but only for adolescents with episodic major depression. In conclusion, the risk for future labor market marginalization is elevated among depressed adolescents, particularly those presenting with persistent depressive disorder. Targeted interventions seem crucial to mitigate the long-lasting impact of early-onset depression.

The link between social communication and mental health from childhood to young adulthood: A systematic review

This systematic review investigates the current state of the literature on the association between social communication (SC) skills and mental health outcomes in children and young adults. We ran searches using terms describing SC and mental health in the following databases: PubMed, the Psychology and Behavioral Sciences Collection, APA PsychInfo, the Education Resource Information Center (ERIC) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). We included studies that both measured SC before age 21 years and assessed a mental health component, such as behavior/conduct problems, anxiety, depression, or emotional problems, before age 30. Only peer-reviewed articles published in or after 2000 were retained. In total, 27 studies were included in the narrative synthesis. Overall, the methodological quality was good. A longitudinal design was used in 12 studies, seven of which sourced data from the Avon Longitudinal Study of Parents and Children. Most studies investigated the broad concept of pragmatic language and its influence on internalizing, externalizing, and peer-relationship problems. The analyzed publications included population-based studies and studies investigating special populations with existing mental health problems or at increased risk of developing them. The population-based cross-sectional studies showed significantly higher rates of SC problems in children with mental health problems while those with a longitudinal design found earlier onset and more persistent mental health problems in children who had the most severe SC difficulties. Studies with special populations confirmed more SC problems as compared to typically developing children and worse mental health outcomes in children with additional SC difficulties. The available literature thus shows consistently significant, mostly moderate associations between SC skills and mental health outcomes. SC difficulties earlier in life can predict mental health problems and impact their trajectories.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=286598], identifier [CRD42022286598].

Intergenerational transmission of parental neuroticism to emotional problems in 8-year-old children: Genetic and environmental influences

Background

Children of parents with high levels of neuroticism tend to have high neuroticism themselves as well as increased risk of experiencing symptoms of anxiety and depression. It is not yet clear how much of this link is attributable to a potential effect of parent on child (e.g., via a socializing effect) versus to shared genetic risk. We aimed to determine whether there is an intergenerational association after accounting for genetic transmission and assortative mating.

Methods

We used data from the Norwegian Mother, Father and Child Cohort Study including 11,088 sibling pairs in the parental generation, their partners (N = 22,176) and their offspring (N = 26,091). Exposures were maternal and paternal neuroticism (self-reported), and the outcomes were neuroticism, symptoms of depression, and symptoms of anxiety in 8-year-old children (mother-reported).

Results

After accounting for assortative mating in parents (phenotypic r = 0.26) and genetic transmission (explaining 0%-18% of the mother-offspring correlations), potential maternal effects explained 80% (95% CI = 47-95) of the association with offspring neuroticism (mother-child r = 0.31), 78% (95% CI = 66-89) of the association with offspring depressive symptoms (r = 0.31), and 98% (95% CI = 45-112) of the association with offspring anxiety symptoms (r = 0.16). Intergenerational transmission of genetic variants associated with paternal neuroticism accounted for ∼40% (CI = 22%-58%) of the father-offspring correlations with neuroticism and symptoms of depression (r = 0.13 and 0.13, respectively) but none with offspring symptoms of anxiety (r = 0.05). The remaining father-offspring correlations were explained by maternal influences through assortative mating.

Conclusions

These results are consistent with direct effects between maternal and offspring neuroticism and between maternal neuroticism and offspring symptoms of anxiety and depression. Further understanding of these intergenerational processes will require an adequate model of how these constructs (neuroticism, anxiety and depression) relate to each other within generations.

Polygenic risk for depression, anxiety and neuroticism are associated with the severity and rate of change in depressive symptoms across adolescence

BACKGROUND

Adolescence marks a period where depression will commonly onset. Twin studies show that genetic influences play a role in how depression develops and changes across adolescence. Recent genome-wide association studies highlight that common genetic variants - which can be combined into polygenic risk scores (PRS) - are also implicated in depression. However, the role of PRS in adolescent depression and changes in adolescent depression is not yet understood. We aimed to examine associations between PRS for five psychiatric traits and depressive symptoms measured across adolescence using cross-sectional and growth-curve models. The five PRS were as follows: depression (DEP), major depressive disorder (MDD), anxiety (ANX), neuroticism (NEU) and schizophrenia (SCZ).

METHODS

We used data from over 6,000 participants of the Avon Longitudinal Study of Parents and Children (ALSPAC) to examine associations between the five PRS and self-reported depressive symptoms (Short Mood and Feelings Questionnaire) over 9 occasions from 10 to 24 years. The PRS were created from well-powered genome-wide association studies conducted in adult populations. We examined cross-sectional associations between the PRS at each age and then again with longitudinal trajectories of depressive symptoms in a repeated measures framework using multilevel growth-curve analysis to examine the severity and the rate of change.

RESULTS

There was strong evidence that higher PRS for DEP, MDD and NEU were associated with worse depressive symptoms throughout adolescence and into young adulthood in our cross-sectional analysis, with consistent associations observed across all nine occasions. Growth-curve analyses provided stronger associations (as measured by effect sizes) and additional insights, demonstrating that individuals with higher PRS for DEP, MDD and NEU had steeper trajectories of depressive symptoms across development, all with a greater increasing rate of change during adolescence. Evidence was less consistent for the ANX and SCZ PRS in the cross-sectional analysis, yet there was some evidence for an increasing rate of change in adolescence in the growth-curve analyses with the ANX PRS.

CONCLUSIONS

These results show that common genetic variants as indexed by varying psychiatric PRS show patterns of specificity that influence both the severity and rate of change in depressive symptoms throughout adolescence and then into young adulthood. Longitudinal data that make use of repeated measures designs have the potential to provide greater insights how genetic factors influence the onset and persistence of adolescent depression.