Genetics of childhood and adolescent depression: insights into etiological heterogeneity and challenges for future genomic research

Cross-continental environmental and genome-wide association study on children and adolescent anxiety and depression

Anxiety and depression in children and adolescents warrant special attention as a public health concern given their devastating and long-term effects on development and mental health. Multiple factors, ranging from genetic vulnerabilities to environmental stressors, influence the risk for the disorders. This study aimed to understand how environmental factors and genomics affect children and adolescents anxiety and depression across three cohorts: Adolescent Brain and Cognitive Development Study (US, age of 9-10; N=11,875), Consortium on Vulnerability to Externalizing Disorders and Addictions (INDIA, age of 6-17; N=4,326) and IMAGEN (EUROPE, age of 14; N=1888). We performed data harmonization and identified the environmental impact on anxiety/depression using a linear mixed-effect model, recursive feature elimination regression, and the LASSO regression model. Subsequently, genome-wide association analyses with consideration of significant environmental factors were performed for all three cohorts by mega-analysis and meta-analysis, followed by functional annotations. The results showed that multiple environmental factors contributed to the risk of anxiety and depression during development, where early life stress and school support index had the most significant and consistent impact across all three cohorts. In both meta, and mega-analysis, SNP rs79878474 in chr11p15 emerged as a particularly promising candidate associated with anxiety and depression, despite not reaching genomic significance. Gene set analysis on the common genes mapped from top promising SNPs of both meta and mega analyses found significant enrichment in regions of chr11p15 and chr3q26, in the function of potassium channels and insulin secretion, in particular Kv3, Kir-6.2, SUR potassium channels encoded by the KCNC1, KCNJ11, and ABCCC8 genes respectively, in chr11p15. Tissue enrichment analysis showed significant enrichment in the small intestine, and a trend of enrichment in the cerebellum. Our findings provide evidences of consistent environmental impact from early life stress and school support index on anxiety and depression during development and also highlight the genetic association between mutations in potassium channels, which support the stress-depression connection via hypothalamic-pituitary-adrenal axis, along with the potential modulating role of potassium channels.

The relationship between weight-related indicators and depressive symptoms during adolescence and adulthood: results from two twin studies

BACKGROUND

The association between weight and depressive symptoms is well established, but the direction of effects remains unclear. Most studies rely on body mass index (BMI) as the sole weight indicator, with few examining the aetiology of the association between weight indicators and depressive symptoms.

METHODS

We analysed data from the Twins Early Development Study (TEDS) and UK Adult Twin Registry (TwinsUK) (7658 and 2775 twin pairs, respectively). A phenotypic cross-lagged panel model assessed the directionality between BMI and depressive symptoms at ages 12, 16, and 21 years in TEDS. Bivariate correlations tested the phenotypic association between a range of weight indicators and depressive symptoms in TwinsUK. In both samples, structural equation modelling of twin data investigated genetic and environmental influences between weight indicators and depression. Sensitivity analyses included two-wave phenotypic cross-lagged panel models and the exclusion of those with a BMI <18.5.

RESULTS

Within TEDS, the relationship between BMI and depression was bidirectional between ages 12 and 16 with a stronger influence of earlier BMI on later depression. The associations were unidirectional thereafter with depression at 16 influencing BMI at 21. Small genetic correlations were found between BMI and depression at ages 16 and 21, but not at 12. Within TwinsUK, depression was weakly correlated with weight indicators; therefore, it was not possible to generate precise estimates of genetic or environmental correlations.

CONCLUSIONS

The directionality of the relationship between BMI and depression appears to be developmentally sensitive. Further research with larger genetically informative samples is needed to estimate the aetiological influence on these associations.

Maternal psychosocial stress during pregnancy and offspring neurobehavioral outcomes during early childhood in the Healthy Start Study

PURPOSE

We evaluate singular and combined effects of prenatal maternal depression and stress on early childhood neurobehavioral outcomes among 536 mother-child pairs.

METHODS

First, we used multivariable linear regression to investigate associations of women's Edinburgh Postnatal Depression Scale (EPDS) score and Perceived Stress Scale (PSS) score, separately, with offspring Child Behavior Checklist score. Next, to assess the combined effect of EPDS and PSS, we dichotomized each score at the fourth versus first to third quartiles and created a four-level variable comprising combinations of high and low depression and stress. Across all models, we accounted for household chaos, hubbub, and order scale (CHAOS) score, an indicator of the household environment associated with offspring behavioral outcomes.

RESULTS

Each one-unit increment in maternal EPDS and PSS scores corresponded with 0.75 (95% CI: 0.53, 0.96) and 0.72 (95% CI: 0.48, 0.95) units higher offspring total problems T-score, respectively. Children of women with high EPDS and PSS had highest T-scores for total problems. All associations remained materially unchanged after adjustment for CHAOS score.

CONCLUSIONS

Prenatal maternal depression and stress is associated with worse neurobehavioral outcomes among offspring, with the most unfavorable outcomes among children whose mothers had high scores for both EPDS and PSS.

Bidirectional effects of parental and adolescent symptom change in trauma-focused cognitive behavioral therapy

OBJECTIVE

The current study examines dynamic, bidirectional associations between parent and adolescent symptom improvement in response to children's therapy for posttraumatic stress disorder (PTSD).

METHOD

Data were collected from a racially and ethnically heterogeneous sample of 1,807 adolescents (age 13-18 years old; 69% female) and a parent participating in Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) at a community outpatient behavioral health clinic. Parents self-reported their depressive symptoms and youth self-reported their PTSD and depressive symptoms at the onset of treatment and every three months for up to nine months. Using a bivariate dual change score model (BDCSM) we examine: (a) individual dyad members' change in symptoms and (b) the bidirectional associations between changes in the parent's and youth's symptoms across treatment.

RESULTS

Parents' and adolescents' symptoms at the start of treatment were correlated and both parents' and adolescents' symptoms decreased over the course of treatment. Parents' elevated depressive symptoms at each time point contributed to smaller decreases in their children's PTSD and depressive symptoms at the subsequent time point. Adolescents' elevated symptoms at each time point contributed to greater decreases in their parents' symptoms at the subsequent time point.

CONCLUSIONS

These findings highlight the impact that parents and children have on each other's response to children's trauma-focused psychotherapy. Notably, parents' depressive symptoms appeared to slow their children's progress in treatment, suggesting that attending to parents' symptoms and providing them with supportive services may be an important adjunct to children's interventions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Annual Research Review: Emotion processing in offspring of mothers with depression diagnoses - a systematic review of neural and physiological research

BACKGROUND

Theories of the intergenerational transmission of depression emphasize alterations in emotion processing among offspring of depressed mothers as a key risk mechanism, raising questions about biological processes contributing to these alterations. The objective of this systematic annual research review was to examine and integrate studies of the associations between maternal depression diagnoses and offspring's emotion processing from birth through adolescence across biological measures including autonomic psychophysiology, electroencephalography (EEG), magnetoencephalography (MEG), event-related potentials (ERP), and structural and functional magnetic resonance imaging (MRI).

METHODS

The review was conducted in accordance with the PRISMA 2020 standards. A systematic search was conducted in PsycInfo and PubMed in 2022 for studies that included, 1) mothers with and without DSM-defined depressive disorders assessed via a clinical or diagnostic interview, and 2) measures of offspring emotion processing assessed at the psychophysiological or neural level between birth and 18 years of age.

RESULTS

Findings from 64 studies indicated that young offspring of mothers with depression histories exhibit heightened corticolimbic activation to negative emotional stimuli, reduced left frontal brain activation, and reduced ERP and mesocorticolimbic responses to reward cues compared to offspring of never-depressed mothers. Further, activation of resting-state networks involved in affective processing differentiate offspring of depressed relative to nondepressed mothers. Some of these alterations were only apparent among youth of depressed mothers exposed to negative environmental contexts or exhibiting current emotional problems. Further, some of these patterns were observable in infancy, reflecting very early emerging vulnerabilities.

CONCLUSIONS

This systematic review provides evidence that maternal depression is associated with alterations in emotion processing across several biological units of analysis in offspring. We present a preliminary conceptual model of the role of deficient emotion processing in pathways from maternal depression to offspring psychopathology and discuss future research avenues addressing limitations of the existing research and clinical implications.

Cross-continental environmental and genome-wide association study on children and adolescent anxiety and depression

Anxiety and depression in children and adolescents warrant special attention as a public health issue given their devastating and long-term effects on development and mental health. Multiple factors, ranging from genetic vulnerabilities to environmental stressors, influence the risk for the disorders. This study aimed to understand how environmental factors and genomics affect children and adolescents anxiety and depression across three cohorts: Adolescent Brain and Cognitive Development Study (US, age of 9-10), Consortium on Vulnerability to Externalizing Disorders and Addictions (INDIA, age of 6-17) and IMAGEN (EUROPE, age of 14). We performed data harmonization and identified the environmental impact on anxiety/depression using a linear mixed-effect model, recursive feature elimination regression, and the LASSO regression model. Subsequently, genome-wide association analyses with consideration of significant environmental factors were performed for all three cohorts by mega-analysis and meta-analysis, followed by functional annotations. The results showed that multiple environmental factors contributed to the risk of anxiety and depression during development, where early life stress and school risk had the most significant and consistent impact across all three cohorts. Both meta and mega-analysis identified a novel SNP rs79878474 in chr11p15 to be the most promising SNP associated with anxiety and depression. Gene set analysis on the common genes mapped from top promising SNPs of both meta and mega analyses found significant enrichment in regions of chr11p15 and chr3q26, in the function of potassium channels and insulin secretion, in particular Kv3, Kir-6.2, SUR potassium channels encoded by the KCNC1, KCNJ11, and ABCCC8 genes respectively, in chr11p15. Tissue enrichment analysis showed significant enrichment in the small intestine and a trend of enrichment in the cerebellum. Our findings provide evidence of consistent environmental impact from early life stress and school risks on anxiety and depression during development and also highlight the genetic association between mutations in potassium channels along with the potential role of the cerebellum region, which are worthy of further investigation.

Shared genetic influences between depression and conduct disorder in children and adolescents: A systematic review

INTRODUCTION

The co-occurrence between major depression disorder (MDD) and conduct disorder (CD) is common across development and represents a significant risk factor for future psychiatric problems and long-term impairment. Large-scale quantitative genetic studies suggest that the MDD-CD co-occurrence may be partly explained by shared genetic vulnerability factors, in line with transdiagnostic models of psychopathology, but no systematic synthesis of the literature is currently available.

METHODS

We therefore conducted a systematic review of the available genetic literature on the co-occurrence between MDD and CD in children and adolescents. We identified 10 eligible studies, including 5 cross-sectional bivariate/multivariate twin studies, 3 longitudinal bivariate/multivariate twin studies, and 2 latent profile/trajectory twin studies.

RESULTS

Most of the reviewed studies found a strong contribution of shared genetic factors on the covariation between depression and conduct problems, in line with the prominent effect of a common genetic liability across development.

LIMITATIONS

The scientific literature on this psychiatric comorbidity is still limited, as it solely consists of twin studies from high income countries.

CONCLUSION

Considering the joint burden of MDD and CD on youth, families and society worldwide, future studies are needed to better investigate the shared risk processes of these frequently co-occurring conditions, in order to inform new treatments through personalized medicine.

Polygenic scores for schizophrenia and major depression are associated with psychosocial risk factors in children: evidence of gene-environment correlation

BACKGROUND

Whilst genetic and environmental risk factors for schizophrenia (SCZ) and major depressive disorder (MDD) have been established, it is unclear whether exposure to environmental risk factors is genetically confounded by passive, evocative or active gene-environment correlation (rGE).

STUDY OBJECTIVE

This study aims to investigate: (a) whether the genetic risk for SCZ/MDD in children is correlated with established environmental and psychosocial risk factors in two British community samples, the 1958 National Child Development Study (NCDS) and the Millennium Cohort Study (MCS), (b) whether these associations vary between both psychopathologies, and (c) whether findings differ across the two cohorts which were born 42 years apart.

METHODS

Polygenic risk scores (PRS) from existing large genome-wide associations studies (GWAS) were applied to test the correlation between the child genetic risk for SCZ/MDD and known environmental risk factors. In addition, parental and child genetic data from MCS were used to distinguish between passive and evocative rGE.

RESULTS

The child polygenic risk for SCZ and MDD was correlated with single parenthood in MCS. Moreover, the lack of father's involvement in child care was associated with the genetic risk for SCZ in NCDS. However, we also found associations between several indicators of low socioeconomic status and heightened genetic risk for MDD in children in both cohorts. Further, the genetic risk for MDD was associated with parental lack of interest in the child's education in NCDS as well as more maternal smoking and less maternal alcohol consumption during childhood in MCS. According to sensitivity analyses in MCS (controlling for parental genotype), more than half of our significant correlations reflected passive rGE.

CONCLUSIONS

Findings suggest that several established environmental and psychosocial risk factors for SCZ and MDD are at least partially associated with children's genetic risk for these psychiatric disorders.

Validation of the short Mood and Feelings Questionnaire in young adulthood

Depression often onsets in adolescence and is associated with recurrence in adulthood. There is a need to identify and monitor depression symptoms across adolescence and into young adulthood. The short Mood and Feelings Questionnaire (sMFQ) is commonly used to measure depression symptoms in adolescence but has not been validated in young adulthood. This study aimed to (1) examine whether the sMFQ is valid in young adulthood, and (2) identify cut-points best capturing DSM-5 depression diagnosis at age 25 METHODS: The sample included participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) at age 25 (n = 4098). Receiver Operating Characteristic analyses examined how well the self-rated sMFQ discriminates between cases and non-cases of DSM-5 Major Depressive Disorder (MDD) classified using the self-rated Development and Well Being Assessment. Sensitivity and specificity values were used to identify cut-points on the sMFQ RESULTS: The sMFQ had high accuracy for discriminating MDD cases from non-cases at age 25. The commonly used cut-point in adolescence (≥12) performed well at this age, best balancing sensitivity and specificity. However, a lower cut-point (≥10) may be appropriate when favouring sensitivity over specificity e.g., in context of screening. Sensitivity analyses suggested similar results for males and females LIMITATIONS: ALSPAC is a longitudinal population cohort that suffers from non-random attrition CONCLUSIONS: The sMFQ is a valid measure of depression in young adults in the general population. It can be used to screen for and monitor depression across adolescence and early adulthood.

Maternal Depression History Moderates the Association Between Criticism (but not Praise) and Depressive Symptoms in Youth

Children of mothers with past depression are at increased risk for developing the disorder themselves; however, the specific factors that increase their risk are unclear. Aberrant reactivity to social experiences may be one characteristic that increases risk for depression in offspring. This study investigates whether mothers' depression history is associated with increased reactivity to criticism and decreased reactivity to praise in offspring by examining 72 youths (ages 8-15). Every evening for 21 days, youths reported their depressive symptoms and whether they were criticized and/or praised by their mothers, fathers, siblings, and friends, resulting in 1,382 data entries across participants. Mothers reported their own depression history and current depressive symptoms. Maternal depression history moderated offspring's response to criticism. Although all youths reacted to perceived criticism from family members with transient increases of depressive symptoms, only children of mothers with higher (vs. lower) levels of past depression exhibited cumulative, person-level associations between perceived criticism and their own depressive symptoms. Additionally, only children of depressed mothers exhibited increases in depressive symptoms on days in which they were criticized by friends. Perceived parental praise was associated with lower levels of depression in youths regardless of maternal depression. Youth depressive symptoms were more strongly related to their parents' (vs. siblings or friends) criticism and praise, highlighting parents' more central role in youth depression risk. Taken together, our results reveal that maternal depression history is associated with increased reactivity to perceived criticism across relational contexts potentially contributing to youths' risk for developing depression.

Effect of one year krill oil supplementation on depressive symptoms and self-esteem of Dutch adolescents: A randomized controlled trial

INTRODUCTION

Observational studies have shown a relationship between omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) and depression in adolescents. However, n-3 LCPUFA supplementation studies investigating the potential improvement in depressive feelings in adolescents from the general population are missing.

METHODS

A one-year double-blind, randomized, placebo controlled krill oil supplementation trial was conducted in two cohorts. Cohort I started with 400 mg eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or placebo, after three months this increased to 800 mg EPA and DHA per day, whilst cohort II started with this higher dose. Omega-3 Index (O3I) was monitored via finger-prick blood measurements. At baseline, six and 12 months participants completed the Centre for Epidemiologic Studies Depression Scale (CES-D) and the Rosenberg Self Esteem questionnaire (RSE). Adjusted mixed models were run with treatment allocation/O3I as predictor of CES-D and RSE scores.

RESULTS

Both intention-to-treat and assessing the change in O3I analyses did not show significant effects on CES-D or RSE scores.

CONCLUSION

There is no evidence for less depressive feelings, or higher self-esteem after one year of krill oil supplementation. However, due to a lack of adherence and drop-out issues, these results should be interpreted with caution.

How important are parents in the development of child anxiety and depression? A genomic analysis of parent-offspring trios in the Norwegian Mother Father and Child Cohort Study (MoBa)

BACKGROUND

Many studies detect associations between parent behaviour and child symptoms of anxiety and depression. Despite knowledge that anxiety and depression are influenced by a complex interplay of genetic and environmental risk factors, most studies do not account for shared familial genetic risk. Quantitative genetic designs provide a means of controlling for shared genetics, but rely on observed putative exposure variables, and require data from highly specific family structures.

METHODS

The intergenerational genomic method, Relatedness Disequilibrium Regression (RDR), indexes environmental effects of parents on child traits using measured genotypes. RDR estimates how much the parent genome influences the child indirectly via the environment, over and above effects of genetic factors acting directly in the child. This 'genetic nurture' effect is agnostic to parent phenotype and captures unmeasured heritable parent behaviours. We applied RDR in a sample of 11,598 parent-offspring trios from the Norwegian Mother, Father and Child Cohort Study (MoBa) to estimate parental genetic nurture separately from direct child genetic effects on anxiety and depression symptoms at age 8. We tested for mediation of genetic nurture via maternal anxiety and depression symptoms. Results were compared to a complementary non-genomic pedigree model.

RESULTS

Parental genetic nurture explained 14% of the variance in depression symptoms at age 8. Subsequent analyses suggested that maternal anxiety and depression partially mediated this effect. The genetic nurture effect was mirrored by the finding of family environmental influence in our pedigree model. In contrast, variance in anxiety symptoms was not significantly influenced by common genetic variation in children or parents, despite a moderate pedigree heritability.

CONCLUSIONS

Genomic methods like RDR represent new opportunities for genetically sensitive family research on complex human traits, which until now has been largely confined to adoption, twin and other pedigree designs. Our results are relevant to debates about the role of parents in the development of anxiety and depression in children, and possibly where to intervene to reduce problems.

Prospective study on cytokine levels in medication-naïve adolescents with first-episode major depressive disorder

BACKGROUND

Evidence suggests that depression is correlated with immune-inflammatory responses, and efforts have been made to identify the relationships between depression and inflammatory markers. This study investigated the level of cytokines before and after treatment for major depressive disorder (MDD) in medication-naïve adolescents with first-episode MDD and compared them with the levels in healthy adolescents. The relationship between cytokine levels and the severity of depressive symptoms was also examined.

METHODS

Twenty-five adolescents with MDD and 25 healthy controls aged 13 to 18 years were included in the study. Blood samples were obtained, and depression severity was assessed twice in the MDD group before and after treatment and once in the healthy group.

RESULTS

When compared with healthy controls, adolescents with MDD had lower levels of interleukin 2 (IL-2), interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α) and IL-10 before treatment and higher levels of IL-2, IFN-γ, and IL-10 after treatment. In addition, the IFN-γ levels correlated with depressive severity scores in both the Children's Depression Inventory (CDI) and Hamilton Depression Rating Scale (HDRS). The IL-10 level correlated with depressive severity only on the HDRS.

LIMITATIONS

The sample size was small, and the 12-week follow-up time after treatment was relatively short.

CONCLUSION

IL-2, IFN-γ, TNF-α, and IL-10 levels in medication-naïve adolescents with first-episode MDD differed from those in healthy controls. The levels of IL-2, IFN-γ, and IL-10 were altered after antidepressant treatment. Further, the IFN-γ and IL-10 levels correlated with the severity of depressive symptoms.

Maternal vitamin D status during pregnancy and offspring risk of childhood/adolescent depression: Results from the Avon Longitudinal Study of Parents and Children (ALSPAC)

BACKGROUND

Low maternal vitamin D levels [serum 25-hydroxyvitamin D (25(OH)D)] during pregnancy have been linked to offspring neuropsychiatric outcomes such as schizophrenia and autism, but studies on depression are lacking. We examined the association between maternal vitamin D status during pregnancy and offspring depression during childhood and adolescence and investigated whether any associations were modified by offspring genetic risk for depression.

METHODS

Mother-singleton birth offspring pairs in the Avon Longitudinal Study of Parents and Children (ALSPAC) that had maternal 25(OH)D measurements, offspring genetic data, and offspring depression measures collected in childhood (mean age=10.6 years; n = 2938) and/or adolescence (mean age=13.8 years; n = 2485) were included in the analyses. Using multivariable logistic regression, we assessed associations between maternal vitamin D status and offspring polygenic risk score (PRS) for depression on childhood/adolescent depression risk.

RESULTS

There was no evidence for an association between maternal vitamin D status during pregnancy and offspring depression in childhood (p = 0.72) or adolescence (p = 0.07). Offspring depression PRS were independently associated with childhood depression (p = 0.003), but did not interact with maternal vitamin D status. These results were robust to adjustments for potential confounders and different cut-offs for vitamin D insufficiency/deficiency.

LIMITATIONS

25(OH)D measurements were only available at a single time point during pregnancy.

CONCLUSION

These findings suggest that maternal vitamin D status during pregnancy does not affect an offspring's risk for early life depression.

Prospective Bidirectional Associations between Attachment and Depressive Symptoms from Middle Childhood to Adolescence

Insecure attachment to parents consistently correlates with adolescent depression. However, the order of cause and effect, the impact of confounding, and gender disparities in this relationship remain unresolved. The present study therefore examined the prospective associations between attachment relationships to mothers and fathers and depressive symptoms in a community sample of Spanish children (n = 904; 49.4% females) assessed biennially from age 10-16 years, net of all unmeasured time-invariant confounding. Insecure relationships predicted depressive symptoms, and more so among girls, but depressive symptoms also forecasted worsened attachment relationships. At ages 12-14, mother-child attachment proved to be more important for the development of depressive symptoms than father-child attachment. These findings reveal a pattern of reciprocal influence between attachment relationships and depressive symptoms that appears to vary as a function of the parental and child's gender and developmental period. Thus, efforts aimed at strengthening the parent-child attachment relationship-across the transition from middle childhood to adolescence-may prevent or reduce depressive symptoms, especially by targeting mothers and female adolescents.

Coping strategies and self-esteem in the high-risk offspring of bipolar parents

OBJECTIVES

This study investigated whether there were differences in coping strategies and self-esteem between offspring of parents with bipolar disorder (high-risk) and offspring of unaffected parents (control), and whether these psychological factors predicted the onset and recurrence of mood episodes.

METHODS

High-risk and control offspring were followed longitudinally as part of the Flourish Canadian high-risk bipolar offspring cohort study. Offspring were clinically assessed annually by a psychiatrist using semi-structured interviews and completed a measure of coping strategies and self-esteem.

RESULTS

In high-risk offspring, avoidant coping strategies significantly increased the hazard of a new onset Diagnostic and Statistical Manual of Mental Disorders, 4th Edition twice revised mood episode or recurrence (hazard ratio: 1.89, p = 0.04), while higher self-esteem significantly decreased this hazard (hazard ratio: 2.50, p < 0.01). Self-esteem and avoidant coping significantly interacted with one another ( p < 0.05), where the risk of a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition twice revised new onset mood episode or recurrence was only significantly increased among high-risk offspring with both high avoidant coping and low self-esteem.

CONCLUSION

A reduction of avoidant coping strategies in response to stress and improvement of self-esteem may be useful intervention targets for preventing the new onset or recurrence of a clinically significant mood disorder among individuals at high familial risk.

Adolescent and adult differences in major depression symptom profiles

BACKGROUND

Depression is the leading global cause of disability and often begins in adolescence. The genetic architecture and treatment response profiles for adults and adolescents differ even though identical criteria are used to diagnose depression across different age groups. There is no clear consensus on how these groups differ in their symptom profiles.

METHODS

Using data from a two-generation family study, we compared the presentation of DSM-IV depressive symptoms in adolescents and adults with MDD (Major Depressive Disorder). We also compared DSM-IV depressive symptom counts using latent class analysis.

RESULTS

Vegetative symptoms (appetite and weight change, loss of energy and insomnia) were more common in adolescent MDD than adult MDD. Anhedonia/loss of interest and concentration problems were more common in adults with MDD. When using latent class analysis to look at depressive symptoms, a vegetative symptom profile was also seen in adolescent depression only.

LIMITATIONS

Adults and adolescents were recruited in different ways. Adolescent cases were more likely to be first-onset while adult cases were recurrences. It was not possible to examine how recurrence affected adolescent depression symptom profiles.

CONCLUSION

Differences in how depression presents in adolescents and adults may be consistent with different pathophysiological mechanisms. For adolescents, we found that vegetative/physical disturbances were common (loss of energy, changes in weight, appetite and sleep changes). For adults, anhedonia/loss of interest and concentration difficulties were more common.

Parenting mediates the impact of maternal depression on child internalizing symptoms

BACKGROUND

To examine the potential mediating role of parenting behaviors in the longitudinal, bidirectional relationships between maternal depression and child internalizing symptoms (i.e. depression and anxiety).

METHODS

We analyzed data from 4,581 mother-child dyads from the Fragile Families and Child Wellbeing Study, assessed when the child was 3, 5, and 9 years old. Data included maternal depression diagnosis, child internalizing symptoms, and parenting behaviors (i.e. psychological aggression, nonviolent discipline, and physical assault). Data were analyzed using cross-lagged panel models.

RESULTS

Results indicated bidirectional relationships between maternal depression and child internalizing symptoms over childhood. Mediation analyses suggested that maternal depression led to subsequent increased psychological aggression toward their child, which in turn led to increased child internalizing symptoms. Nonviolent discipline and physical assault did not mediate this relationship. However, greater use of nonviolent discipline at age 5 among all parents predicted higher child internalizing symptoms at age 9. No parenting behaviors were both predicted by earlier child internalizing symptoms and predictive of subsequent maternal depression.

CONCLUSIONS

Our results suggest a bidirectional relationship between child and maternal internalizing psychopathology that is partially explained by depressed mothers' greater use of psychological aggression toward their children. It is important to note that the size of these effects were small, suggesting that the relationship between parent and child psychopathology is likely additionally explained by factors not assessed in the current study. Nonetheless, these results have implications for prevention and intervention strategies targeting child anxiety and depression.

Genetics of depressive symptoms in adolescence

BACKGROUND

Despite many attempts to understand the genetic architecture of depression, little progress has been made. The majority of these studies, however, have been carried out in adults and do not account for the potential influence of development.

METHODS

The Avon Longitudinal Study of Parents and Children (ALSPAC) is a longitudinal pregnancy cohort which recruited participants between April 1991 and December 1992. Analyses were replicated in two independent European cohorts. Genome-wide complex trait analysis (GCTA) software was used to investigate SNP-heritability (h2SNP) of depression across adolescence, the role of puberty was investigated by stratifying these estimates according to pubertal onset. Genome-wide association studies were performed to identify genetic variants associated with depression at different stages of development.

RESULTS

Heritability was estimated between the ages of 11 and 18 with sample sizes ranging from 3289 to 5480. Heritability was low with an apparent peak was found at age 13 (h2 = 0.17, p = 0.006). Confidence intervals around these estimates suggest an upper-bound to h2SNP of around 30%. A variant located on chromosome 7 was found to be associated with depressive symptoms at age 13 in ALSPAC (rs138191010: β = 0.142, p = 2.51 × 10-8), although this was not replicated.

CONCLUSIONS

Although power is a potential limitation, the observed patterns provide interesting hypotheses surrounding the heritability of depression at different developmental stages. We found substantially lower estimates for depressive symptoms at age 11 (0.07) compared to those previously estimated in adults (0.21). We also found a peak in heritability at age 13. These findings suggest environmental factors are likely to be more important in the aetiology of depressive symptoms in early adolescence than in adulthood.

Developmental change in the association between adolescent depressive symptoms and the home environment: results from a longitudinal, genetically informative investigation

BACKGROUND

Depression is already highly prevalent by late adolescence, indicating that research into its developmental emergence should consider earlier risk factors and environmental contexts. The home environment is a key context for children and adolescents throughout development. However, the nature of relationships that exist between aspects of the home environment and the development of depressive symptoms cannot be assumed. Genetically informative studies have been used to provide insights about the aetiology of such relationships, often finding them to be partly confounded by the influence of children's genes. Here, we investigate developmental change in the aetiology of the association between aspects of the home environment and depressive symptoms at the onset of adolescence.

METHODS

We used longitudinal child- and parent-report data from >5,000 twin pairs enrolled in the UK-representative Twins Early Development Study. Multivariate, genetically sensitive structural equation models were used to decompose latent variance and covariance in depressive symptoms (measured at 12 and 16 years) and aspects of the home environment (at 9 and 14 years) into genetic and environmental influences.

RESULTS

Going from childhood to adolescence, genetic influences accounted for an increasing proportion of the association [30% (16-42) of r = .44 in childhood; 40% (25-61) of r = .43 in adolescence], at the expense of shared environmental influences, which decreased from 70% (58-83) to 48% (29-62). Unique environmental influences accounted for a significant proportion of the association in adolescence only [12% (06-18)]. Developmental changes could largely be attributed to subtle shifts in the relative importance of stable aetiological factors, rather than the emergence of influences unique to adolescence.

CONCLUSIONS

These findings emphasise the importance of developmental and aetiological context in interpreting associations between aspects of the home environment and child emotional outcomes.

Profiling depression in childhood and adolescence: the role of conduct problems

BACKGROUND

Depression is typically more common in females and rates rise around puberty. However, studies of children and adolescents suggest that depression accompanied by conduct problems may represent a different subtype not characterised by a female preponderance, with differing risk factors and genetic architecture compared to pure-depression. This study aimed to identify aetiologically distinct profiles of depressive symptoms, distinguished by the presence or absence of co-occurring conduct problems.

METHODS

Latent profile analysis was conducted on a school sample of 1648 children (11-12 years) and replicated in a sample of 2006 twins (8-17 years).

RESULTS

In both samples pure-depressive and conduct-depressive profiles were identified. The pure-depressive profile was associated with female gender, while the conduct-depressive profile was associated with lower cognitive ability but not with gender. Twin analyses indicated possible differences in genetic aetiology.

CONCLUSIONS

There was evidence for aetiologically heterogeneous depression symptom profiles based on the presence or absence of co-occurring conduct problems.

The Involvement of Genes in Adolescent Depression: A Systematic Review

Numerous studies have reported on the roles of genetic factors in the development of depression in adolescents and young adults. However, there are few systematic reviews that update our understanding of adolescent depression with the biological findings identifying the roles of gene expression and/or polymorphism(s). This review systematically summarized the findings that clearly identified the contribution of a gene to the risk of depression in adolescents between the ages of 10 and 19 years old and young adults between the ages of 20 and 25 years old. Data were obtained through searching PubMed, Embase, and Web of Science. A total of 47 studies on early adolescence and three studies on young adults were included in the current review. Most articles studied genes in the serotonergic system (n = 26), dopaminergic system (n = 3), and the Brain-derived neurotropic factor (BDNF) gene (n = 12). 92.3% of studies (24/26) identified positive associations of 5-HTTLPR polymorphism with depressive illness or depressive symptoms. 83.3% of studies (10/12) found positive association between BDNF Val66Met genotype and adolescent depressive symptoms. More studies should be conducted on the 18 genes reported in a few studies to clarify their roles in the risk for adolescent depression.

Predictors of change in depressive symptoms from preschool to first grade

Children's depressive symptoms in the transition from preschool to school are rarely investigated. We therefore tested whether children's temperament (effortful control and negative affect), social skills, child psychopathology, environmental stressors (life events), parental accuracy of predicting their child's emotion understanding (parental accuracy), parental emotional availability, and parental depression predict changes in depressive symptoms from preschool to first grade. Parents of a community sample of 995 4-year-olds were interviewed using the Preschool Age Psychiatric Assessment. The children and parents were reassessed when the children started first grade (n = 795). The results showed that DSM-5 defined depressive symptoms increased. Child temperamental negative affect and parental depression predicted increased, whereas social skills predicted decreased, depressive symptoms. However, such social skills were only protective among children with low and medium effortful control. Further, high parental accuracy proved protective among children with low effortful control and high negative affect. Thus, interventions that treat parental depression may be important for young children. Children with low effortful control and high negative affect may especially benefit from having parents who accurately perceive their emotional understanding. Efforts to enhance social skills may prove particularly important for children with low or medium effortful control.

BDNF Val66Met polymorphism and stressful life events in melancholic childhood-onset depression

INTRODUCTION

Brain-derived neurotrophic factor (BDNF) polymorphisms have been examined for their contribution toward depression with equivocal results. More homogeneous phenotypes might be used to improve our understanding of genetic liability to depression. The aim of our study was to (a) test for an association between the BDNF Val66Met polymorphism and childhood-onset melancholic depression and (b) to examine the interactive effects of stressful life events (SLE) and the Val66Met polymorphism on the risk of childhood-onset melancholic depression.

MATERIALS AND METHODS

A total of 583 depressed probands were involved in this study (162 of the melancholic subtype). Diagnoses were derived through the Interview Schedule for Children and Adolescents - Diagnostic Version and life event data were collected using an Intake General Information Sheet.

RESULTS

Overall, 27.8% of the participants fulfilled the criteria for melancholy. In the melancholic group, the proportion of females was higher (53.1%), although there were more males in the overall depressed sample. We detected no significant differences in genotype or allele frequency between the melancholic and the nonmelancholic depressed group. The BDNF Val66Met polymorphism and SLE interaction was not significantly associated with the melancholy outcome.

CONCLUSION

In our study, females were more prone to developing the early-onset melancholic phenotype. To our knowledge, this is the first study to investigate the differentiating effect of the genotype and the G×E interaction on the melancholic phenotype in a large sample of depressed young patients. We did not find an association between the melancholic subtype of major depression and the BDNF genotype and SLE interaction in this sample, which is representative of the Hungarian clinic-referred population of depressed youths.

Blunted Ventral Striatum Development in Adolescence Reflects Emotional Neglect and Predicts Depressive Symptoms

BACKGROUND

Emotional neglect is associated with multiple negative outcomes, particularly increased risk for depression. Motivated by increasing evidence of reward-related ventral striatum (VS) dysfunction in depression, we investigated the role of developmental changes in VS activity on the emergence of depressive symptomatology as a function of emotional neglect.

METHODS

We examined relationships between longitudinal neuroimaging of reward-related VS activity, assessments of mood, and measures of emotional neglect in 106 participants first scanned between ages 11 to 15 and then 2 years later.

RESULTS

We found that greater levels of emotional neglect were associated with blunted development of reward-related VS activity between the first and second assessments (as indexed by lower residualized change scores). Additionally, we found that decreases in this reward-related VS activity were related to greater depressive symptomatology and partially mediated the association between emotional neglect and subsequent depressive symptomatology.

CONCLUSIONS

Our results provide an important demonstration that blunted development of reward-related VS activity as a function of emotional neglect predicts the emergence of depressive symptoms in adolescents. Further, our results are consistent with emerging evidence for the importance of reward-related VS dysfunction in the etiology and pathophysiology of depression. These results are a first step toward developing the ability to predict, prevent, and treat stress-related psychopathology through the targeting of specific neural phenotypes.

Etiological heterogeneity of symptom dimensions of adolescent depression

The aim was to investigate the underlying factor structure of adolescent depression and etiological heterogeneity in the symptom dimensions of adolescent depression. The sample included 842 pairs of same-sex adolescent twins, among which 613 pairs were monozygotic twins and 229 pairs were dizygotic twins. The ages of the participants ranged from 11 to 17 years (M = 13.64, SD = 1.80). Adolescents' depressive symptoms were assessed using the self-reported Children's Depression Inventory. Exploratory and confirmatory factor analyses were used to explore the factor structure of youth depression and twin genetic analyses were employed to estimate genetic and environmental influences on the derived dimensions. Results showed that adolescent depression encompassed five correlated dimensions: dysphoria mood, somatic symptoms, study and externalizing problems, anhedonia symptoms, and cognitive symptoms. These five symptom dimensions had heterogeneous etiologies: Dysphoria mood, somatic symptoms, and cognitive symptoms were moderately heritable (heritability ranged from 33 to 40%), whereas study and externalizing problems, and anhedonia symptoms were mainly environmentally influenced with minimal genetic basis. Our findings supported the multidimensionality of adolescent depression and the etiological heterogeneity of these symptom dimensions.

Genetic and environmental influences on adolescent rumination and its association with depressive symptoms

Rumination is an important cognitive vulnerability for adolescent and adult depression. However, little is known about the aetiological origins of rumination, as well as its association with depression. Adolescent rumination (self-report) and depressive symptoms (self- and parent-report) were assessed in 674 pairs of same-gender Chinese adolescent twins (11-17 years of age). Females accounted for 53.7 % of the sample. There were significant correlations between self-reported rumination and self-reported depression (r = 0.41), as well as parent-reported adolescent depression (r = 0.22). Genetic influences were significant and modest on all three measures, ranging from 24 % to 42 %. The three measures were also significantly influenced by shared environment, ranging from 20 % to 28 %, and non-shared environmental factors, ranging from 30 % to 56 %. Moreover, the genetic correlations between rumination and depression were significant (within-rater: r(g) = 0.99; cross-rater: r(g) = 0.59) and largely accounted for the phenotypic correlations (within-rater: 68 %; cross-rater: 77 %), while non-shared environmental correlations were also significant (within-rater: r(e) = 0.26; cross-rater: r(e) = 0.12) and accounted for the remainder of the phenotypic correlations (within-rater: 32 %; cross-rater: 23 %). The shared environmental correlations were non-significant. No significant gender and age differences were found in aetiological models. These findings suggest that rumination may be an endophenotype reflecting genetic risk for depression.

The relationship between emotional problems and subsequent school attainment: a meta-analysis

Longitudinal studies have provided mixed findings regarding the relationship between emotional problems and subsequent poor school attainment. A meta-analysis of 26 community-based studies of children and adolescents was performed. Results revealed a prospective association between emotional problems and poor school attainment. More consistent associations were found for depression than anxiety. Moderator analyses indicated that some of the heterogeneity between studies may be due to age and gender, with reduced heterogeneity particularly notable for school grades during early adolescence and for anxiety by gender. Findings suggest that early identification and provision of support for young people with emotional problems may be helpful for improving academic outcomes such as school attainment.

The role of peer rejection in adolescent depression

Adolescence is a period of major risk for depression, which is associated with negative personal, social, and educational outcomes. Yet, in comparison to adult models of depression, very little is known about the specific psychosocial stressors that contribute to adolescent depression, and whether these can be targeted by interventions. In this review, we consider the role of peer rejection. First, we present a comprehensive review of studies using innovative experimental paradigms to understand the role of peer rejection in adolescent depression. We show how reciprocal relationships between peer rejection and depressive symptoms across adolescence powerfully shape and maintain maladaptive trajectories. Second, we consider how cognitive biases and their neurobiological substrates may explain why some adolescents are more vulnerable to the effects of, and perhaps exposure to, peer rejection compared to others. Finally, we draw attention to emerging cognitive and functional magnetic resonance imaging-based neurofeedback training, which by modifying aspects of information processing may promote more adaptive responses to peer rejection. A better understanding of the mechanisms underlying adolescent depression may not only alleviate symptoms during a period of substantial developmental challenges, but may also reduce the burden of the disorder across the lifespan.

A longitudinal study of psychological functioning and academic attainment at the transition to secondary school

This longitudinal study of adolescents in the first year of secondary school, examined the relationship between psychological functioning at the beginning of year 7 (mean age 11.25 years) with attainment at the end of year 7 (mean age 11.78 years). Depressive symptoms, school liking and conduct problems predicted lower attainment across time having controlled for the temporal stability in psychological functioning and attainment. School concerns predicted lower attainment for boys only, and the effects of depressive symptoms on later attainment were significantly stronger for boys compared to girls. School liking - and school concerns for boys - remained significant predictors of attainment when controlling for conduct problems. The transition to secondary school may represent a window of opportunity for developing interventions aimed at improving both pupil psychological functioning and attainment.

Functional brain activation to emotionally valenced faces in school-aged children with a history of preschool-onset major depression

BACKGROUND

Recent research has demonstrated that clinical depression can emerge as early as the preschool period. Here, we examine brain function in children with a history of preschool-onset depression (PO-MDD) in comparison with healthy children.

METHODS

Participants were medication naïve school-aged children (ages 7-11) with PO-MDD (n = 22) or no psychiatric history (n = 16) followed longitudinally as part of the Preschool Depression Study. We used functional magnetic resonance imaging measures of blood oxygen level-dependent signal to examine functional brain activity in response to emotionally valenced faces (sad, fearful, angry, happy, neutral) following a negative mood induction provided to all children.

RESULTS

In categorical group comparisons, children with PO-MDD demonstrated increased activity in parietal cortex in response to sad faces but no differences in brain activity in a priori regions of interest (e.g., amygdala). However, in dimensional analyses, the severity of depression symptoms at the baseline preschool assessment predicted increased responses to sad faces in amygdala, hippocampal, parietal, and orbital frontal regions.

CONCLUSIONS

School-aged children with a history of PO-MDD showed patterns of functional brain responses to emotionally evocative stimuli similar to patterns found in adults and adolescents with major depression. These patterns were most strongly related to the severity of depression during the preschool period, suggesting that the magnitude of early symptoms may be particularly important for understanding altered brain function. These findings suggest that an early episode of depression before age 6 may be associated with enduring brain change or may represent a biomarker that was present even before the preschool episode.

[Cognitive behavior therapy for depression in children and adolescents - procedure, effects, and developments]

Cognitive behavior therapy offers a theoretically and empirically valid therapeutic approach for children and adolescents suffering from depression. It can be recommended according to present guidelines and efficacy studies. Further research and conceptual development, however, is necessary especially regarding the small to moderate effect sizes as well as the lack of long-term efficacy and effect factors. This article gives a short overview of the basics and contents of cognitive behavior therapy for depressive children and adolescents. It furthermore presents the latest findings and an assessment of its efficacy and relevant developments and perspectives.