Genetic studies of affective disorders: should we be starting with childhood onset probands?

The impact of maternal depressive symptoms and traumatic events on early childhood mental health in conflict-affected Timor-Leste

BACKGROUND

Longitudinal studies are needed to examine the association between maternal depression, trauma and childhood mental health in conflict-affected settings.

AIMS

To examine maternal depressive symptoms, trauma-related adversities and child mental health by using a longitudinal path model in conflict-affected Timor-Leste.

METHOD

Women were recruited in pregnancy. At wave 1, 1672 of 1740 eligible women were interviewed (96% response rate). The final sample comprised 1118 women with complete data at all three time points. Women were followed up when the index child was aged 18 months (wave 2) and 36 months (wave 3). Measures included the Edinburgh Postnatal Depression Scale, lifetime traumatic events and the Child Behaviour Checklist. A longitudinal path analysis examined associations cross-sectionally and in a cross-lagged manner across time.

RESULTS

Maternal depressive symptom score was associated with child mental health (cross-sectional association at wave 2, β = 0.35, P < 0.001; cross-sectional association at wave 3, β = 0.33, P < 0.001). The maternal depressive symptom score at wave 1 was associated with child mental health at wave 2 (β = 0.12, P < 0.001), and the maternal depressive symptom score at wave 2 showed an indirect association with child mental health at wave 3 (indirect standardised coefficient 0.23, P < 0.001). There was a time-lagged relationship between child mental health at wave 2 and maternal depression at wave 3 (β = 0.08, P = 0.02).

CONCLUSIONS

Maternal depressive symptoms are longitudinally associated with child mental health, and traumatic events play a role. Maternal depression symptoms are also affected by child mental health. Findings suggest the need for skilled assessment for depression, trauma-informed maternity care and parenting support in a post-conflict country such as Timor-Leste.

Rare variants in SLC6A4 cause susceptibility to major depressive disorder with suicidal ideation in Han Chinese adolescents and young adults

BACKGROUND

Suicidal ideation (SI) is the most serious symptom of major depressive disorder (MDD) and considered an extreme state. The serotonin transporter gene (SLC6A4) plays a significant role in MDD and suicide pathophysiology. Previous studies have revealed an association between common variants of SLC6A4 with the risk of MDD and suicide. However, very few studies have so far focused on the degree to which rare variants of SLC6A4 are responsible for the depression observed in adolescent and young adult suicide patients. The aim of this study was to examine the impact of common and rare variants of SLC6A4 on the risk of Han Chinese adolescents and young adults suffering MDD with SI.

METHODS

Targeted sequencing of the SLC6A4 gene was conducted using FastTarget technology in Han Chinese adolescents and young adults, of which 74 were MDD patients with SI and 150 were healthy controls. Gene-based association analyses of rare variants were performed using enrichment analysis and a cumulative allele test. An allele association study was performed against common variants.

RESULTS

After sequencing and bioinformatics analysis, a total of 15 single nucleotide variants (SNVs) were detected in the targeted regions from all participants, including 9 common and 6 rare variants. Among these, 5 rare variants were identified within the study group. Enrichment analysis of rare variants demonstrated a statistical difference (p = 0.042) between the study and control groups. Using cumulative allele analysis, alternative alleles in the SLC6A4 gene exhibited an association with MDD patients with SI (cumulative allele: OR = 10.18, 95% CI = 1.18-87.32, p = 0.017). No significant association was found between the 9 common SLC6A4 variants and MDD patients with SI.

CONCLUSIONS

Our results suggest that rare variants of SLC6A4 may contribute to a genetic risk of adolescents and young adults suffering MDD with SI.

Age of onset and family history as indicators of polygenic risk for major depression

BACKGROUND

The extent to which earlier age of onset (AO) is a reflection of increased genetic risk for major depression (MD) is still unknown. Previous biometrical research has provided mixed empirical evidence for the genetic overlap of AO with MD. If AO is demonstrated to be relevant to molecular polygenic risk for MD, incorporation of AO as a phenotype could enhance future genetic studies.

METHODS

This research estimated the SNP-based heritability of AO in the China, Oxford and VCU Experimental Research on Genetic Epidemiology (CONVERGE) case-control sample (N = 9,854; MD case, n = 4,927). Common single nucleotide polymorphism heritability of MD was also examined across both high and low median-split AO groups, and best linear unbiased predictor (BLUP) scores of polygenic risk, in split-halves, were used to predict AO. Distributions of genetic risk across early and late AO were compared, and presence of self-reported family history (FH) of MD was also examined as a predictor of AO.

RESULTS

AO was not significantly heritable and polygenic risk derived from the aggregated effects of common genetic variants did not significantly predict AO in any analysis. AO was modestly but significantly lower in cases with a first-degree genetic FH of MD.

CONCLUSIONS

Findings indicate that AO is associated with greater self-reported genetic risk for MD in cases, yet not associated with common variant polygenic risk for MD. Future studies of early MD may benefit more from the examination of important moderating variables such as early life events.

Conversion from bipolar disorder not otherwise specified (BP-NOS) to bipolar I or II in youth with family history as a predictor of conversion

BACKGROUND

Bipolar disorder-not otherwise specified (BD-NOS) is an imprecise, heterogeneous diagnosis that is unstable in youth. This study reports rates of conversion from BD-NOS to BD-I or II in children aged 8-12, and investigates the impact of family history of bipolar disorder and depression on conversion.

METHODS

As part of the Multi-Family Psychoeducational Psychotherapy (MF-PEP) study, 27 children (6-12 years of age) diagnosed with BD-NOS at baseline were reassessed every 6 months over an 18-month period. Family history of bipolar disorder and depression was assessed at baseline.

RESULTS

One-third of the sample converted from BD-NOS to BD-I or II over 18-months. Having a first-degree relative with symptoms of bipolar disorder and having a loaded pedigree for diagnosis of depression each were associated with conversion from BD-NOS to BD-I or II (odds ratio range: 1.09-3.14; relative risk range: 1.06-2.34).

LIMITATIONS

This study had very low power (range: 10-45) given the small sample size, precluding statistical significance of non-parametric Fisher's Exact test findings.

CONCLUSIONS

This study replicates the previous finding of a high rate of conversion from BD-NOS to BD-I or II among youth, and suggests conversion is related to symptoms of bipolar disorder or depression diagnoses in the family history. Additional research is warranted in a larger sample with a longer follow-up period.

Depression in adolescence

Unipolar depressive disorder in adolescence is common worldwide but often unrecognised. The incidence, notably in girls, rises sharply after puberty and, by the end of adolescence, the 1 year prevalence rate exceeds 4%. The burden is highest in low-income and middle-income countries. Depression is associated with substantial present and future morbidity, and heightens suicide risk. The strongest risk factors for depression in adolescents are a family history of depression and exposure to psychosocial stress. Inherited risks, developmental factors, sex hormones, and psychosocial adversity interact to increase risk through hormonal factors and associated perturbed neural pathways. Although many similarities between depression in adolescence and depression in adulthood exist, in adolescents the use of antidepressants is of concern and opinions about clinical management are divided. Effective treatments are available, but choices are dependent on depression severity and available resources. Prevention strategies targeted at high-risk groups are promising.

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

There is heterogeneity between depression in childhood, adolescence and adulthood in terms of the gender composition of affected cases, prevalence, rates of recurrence and risk factors. This raises complex questions for refining the phenotype for molecular genetic studies of depression and the selection of appropriate proband groups. This article aims to provide a review of issues arising from family, twin and adoption studies of relevance to molecular genetic studies, and to summarize molecular genetic findings on childhood/adolescent depression. While retrospective studies of adults suggest greater familial aggregation among those with an earlier age of onset, prospective studies do not confirm this association. In fact, taken together, evidence from family and twin studies suggests that prepubertal depression is more strongly associated with psychosocial adversity, is less heritable and shows lower levels of continuity with adult depression than either adolescent or adult depression. Adolescent depressive symptoms and disorder show similar levels of heritability to depression in adult life, although there is only one twin study of adolescent depressive disorder, and heritability estimates of depressive symptoms vary widely between studies. This variability in heritability estimates is partly attributable to age and informant effects. Adoption studies and other intergenerational transmission designs show that the transmission of depression between parents and children involves genetic and environmental processes, with converging evidence that environmental processes are most important. Molecular genetic studies of childhood/adolescent depression have to date used a candidate gene approach and focused on genes already examined in adult studies. Prospective longitudinal studies of community and high-risk samples are needed to clarify issues of etiological heterogeneity in depression, and these should in turn inform the planning of molecular genetic studies.

Reduced sleep spindle activity in early-onset and elevated risk for depression

OBJECTIVE

Sleep disturbances are common in major depressive disorder (MDD), although polysomnographic (PSG) abnormalities are more prevalent in adults than in children and adolescents with MDD. Sleep spindle activity (SPA) is associated with neuroplasticity mechanisms during brain maturation and is more abundant in childhood and adolescence than in adulthood, and as such, may be a more sensitive measure of sleep alteration than PSG in early-onset depression. This study investigated SPA changes related to early-onset MDD, comparing individuals already ill with MDD and individuals at high-risk for MDD with healthy nondepressed controls.

METHOD

The study included 63 participants (8 to 15 years of age): 21 currently depressed individuals, 21 individuals at high risk for MDD based on positive family history of MDD, and 21 healthy control individuals with no personal or family history of psychiatric illness. All participants maintained a regular sleep/wake schedule for 5 days, followed by 2 nights in the laboratory. SPA was analyzed in Stage 2 of non-rapid eye movement sleep.

RESULTS

SPA differed significantly between groups, particularly in the late part of the night (F(2,62) = 7.3, p = .001). Although the difference was greatest between the MDD and healthy control groups, both the MDD (p = .0004) and at high-risk groups (p = .02) had significantly lower SPA compared with healthy controls. SPA deficit was more prominent in females than in males (F(5,62) = 5.19, p = .005).

CONCLUSIONS

Low SPA characterizes youths with MDD and those at high risk for MDD, particularly girls, suggesting that early-onset depression and risk for the MDD are associated with decreased neuroplasticity.

Prodromal symptoms and atypical affectivity as predictors of major depression in juveniles: implications for prevention

BACKGROUND

Given the long-term morbidity of juvenile-onset major depressive disorder (MDD), it is timely to consider whether more effort should be dedicated to its primary and secondary prevention.

METHODS

We reviewed studies of prodromal symptoms that may herald a first episode pediatric MDD and considered whether that literature has made an impact on secondary prevention (efforts to prevent progression from symptoms to full disorder). We also reviewed studies of children at familial risk for MDD that addressed atypical affectivity and the regulation of sad, dysphoric affect (mood repair) and related physiological systems, and considered whether research in those areas has made an impact on primary prevention of pediatric MDD (efforts to prevent the disorder).

RESULTS

A compelling body of literature indicates that depressive symptoms in youngsters predict subsequent MDD across the juvenile (and early adult) years and that any combination of several symptoms for at least one week is informative in that regard. These findings are echoed in the case selection criteria used by many secondary prevention programs. Convergent findings also indicate that (compared to typical peers) young offspring at familial risk for depression manifest low positive affectivity and compromised mood repair, along with signs of dysfunction in three intertwined physiological systems that contribute to affectivity and mood repair (the hypothalamic-pituitary-adrenal (HPA) axis, cerebral hemispheric asymmetry, and cardiac vagal control). While all these affect-related parameters are suitable for case selection and as intervention targets, they have not yet made an impact on primary prevention programs.

CONCLUSIONS

According to recent meta-analyses, attempts to prevent pediatric depression have not lived up to expectations. Based on our review, possible reasons for this include: (a) the use of case selection criteria that yield samples heterogeneous with regard to whether the symptoms are truly prodromal to an episode of MDD or are trait-like (which could affect response to the intervention), (b) failure to fully capitalize on the broad-ranging literature on vulnerability to pediatric MDD, as evidenced by the infrequent use of family history of depression (a robust index of vulnerability) or combined indices of vulnerability for case selection, and (c) lack of synchrony between dimensions of vulnerability and the content of the prevention program, as indicated by the overwhelming use of cognitive-behavioral interventions, irrespective of subjects' age, developmental readiness, and whether or not they evidenced the relevant cognitive vulnerability. Prevention trials of pediatric MDD could benefit from new approaches to case selection that combine various indices of vulnerability, more effective use of existing findings, and new or modified interventions that are developmentally sensitive.

Intergenerational transmission of multiple problem behaviors: prospective relationships between mothers and daughters

Much of the research examining intergenerational continuity of problems from mother to offspring has focused on homotypic continuity (e.g., depression), despite the fact that different types of mental health problems tend to cluster in both adults and children. It remains unclear whether mothers with multiple mental health problems compared to mothers with fewer or no problems are more likely to have daughters with multiple mental health problems during middle childhood (ages 7 to 11). Six waves of maternal and child data from the Pittsburgh Girls Study (n = 2,451) were used to examine the specificity of effects of maternal psychopathology on child adjustment. Child multiple mental health problems comprised disruptive behavior, ADHD symptoms, depressed mood, anxiety symptoms and somatic complaints, while maternal multiple mental health problems consisted of depression, prior conduct problems and somatic complaints. Generalized Estimating Equations (GEE) was used to examine the prospective relationships between mother’s single and multiple mental health problems and their daughter’s single and multiple mental health problems across the elementary school-aged period (ages 7–11 years). The results show that multiple mental health problems in the mothers predicted multiple mental health problems in the daughters even when earlier mental health problem of the daughters, demographic factors, and childrearing practices were controlled. Maternal low parental warmth and harsh punishment independently contributed to the prediction of multiple mental health problems in their daughter, but mediation analyses showed that the contribution of parenting behaviors to the explanation of girls’ mental health problems was small.

Fear of harm, a possible phenotype of pediatric bipolar disorder: a dimensional approach to diagnosis for genotyping psychiatric syndromes

BACKGROUND

In a prior concordance study of affected sibling pairs with a community diagnosis of pediatric bipolar disorder (PBD) a behavioral phenotype termed Fear of Harm (FOH) was found to have one of the strongest concordance coefficients (rho) between probands and siblings, and the widest contrasts between the rho-estimates for the proband/sibling vs. proband/comparison pairs [Papolos, D., Hennen, J., Cockerham, M.S, Lachman, H., 2007]. A strategy for identifying phenotypic subtypes: concordance of symptom dimensions between sibling pairs who met screening criteria for a genetic linkage study of childhood-onset bipolar disorder using the Child Bipolar Questionnaire (CBQ) was employed. J. Affect. Disord. 99, 27-36.]. We used the Child Bipolar Questionnaire (OUT) (CBQ) to further elucidate this behavioral phenotype of PBD. We hypothesized that selective factors including parent reported symptoms of mania and depression, would be distinguishing features of impairment between groups defined by 1) the magnitude of their score on a continuous measure of FOH, and 2) the high FOH group would have significantly greater levels of severity on course of illness variables. These measures included earlier age of onset of first psychiatric symptoms, first hospitalization, and frequency of psychiatric hospitalizations, as well as, degree of social impairment as determined by exposure to the juvenile justice system and school performance problems.

METHODS

The sample was comprised of children with community diagnoses of bipolar disorder or at risk for the illness based on enriched family history with multiple first degree relatives diagnosed with BPD (N=5335). Included were all subjects who had >40 positively endorsed CBQ symptom items at frequencies of very often, almost always, and always. This group was divided randomly into two groups, the exploratory group (N=2668) and the hypothesis testing (study) group (N=2666). The exploratory group was used for the development of hypotheses and the study group was used to test these hypotheses on a new set of data. All results reported here derive from the latter group. In subsequent analyses, we classified each child as having a high degree of FOH, low FOH, or no FOH. We examined a subset of the sample for differences in age of onset of first psychiatric symptoms, course of illness and measures of symptom severity. These groups were compared using the chi-square procedure for categorical data and the Analysis of Variance (ANOVA) with Scheffe pair wise tests for continuous variables. The Child Bipolar Questionnaire V.2.0, the Yale-Brown Obsessive Compulsive Scale (YBOCS) and the Overt Aggression Scale (OAS) were the principal instruments used to obtain diagnostic information for this study.

RESULTS

We found that children representative of the FOH phenotype when compared to children with PBD who lack this trait had higher indices of severity of mania and depression, as well as other indices that reflect severity and course of illness. Trait factors were derived from a factor analysis of CBQ in a large population of children diagnosed with or at risk for PBD, and used to further elucidate trait features of children with FOH. Children with the FOH traits were also more likely to be defined by six CBQ factors; Sleep/Arousal, Harm to Self and Others, Territorial Aggression, Anxiety, Self-esteem, Psychosis/Parasomnias/Sweet Cravings/Obsessions (PPSO).

LIMITATIONS

This data is derived from samples enriched with bipolar disorder cases. Further validation is needed with samples in which childhood-onset BD is rarer and diagnoses more diverse. Clinician diagnosis was not validated via research interview.

CONCLUSIONS

The FOH phenotype, as defined by a metric derived from combining items from the YBOCS/OAS, is a clinically homogeneous behavioral phenotype of PBD with early age of onset, severe manic and depressive symptoms, and significant social impairment that is strongly associated with 6 CBQ factors and can be easily identified using the CBQ. Through the examination of dimensional features of PBD in an enriched sample of large size, we were able to further refine a phenotype and identify clinical dimensions potentially linked to endophenotypic markers that may prove fruitful in differential diagnosis, treatment and etiological studies of PBD. The nature of the sets of specific symptoms that comprise the FOH factors enabled us to propose a biological model for the phenotype (OUT) that involves a complex orexigenic circuit which links hypothalamic, limbic, and other brain nuclei primarily responsible for the regulation of behavioral and proposed physiological features of the FOH phenotype.

Genome scan in sibling pairs with juvenile-onset mood disorders: Evidence for linkage to 13q and Xq

Mood disorders (bipolar and depressive disorders) in children and adolescents are associated with significant morbidity and mortality. Twin and family studies, for the most part, indicate higher familiality and heritability for mood disorders that onset in childhood/adolescence than those that onset in adulthood. To identify the genetic contribution to mood disorders that onset in childhood/adolescence, we performed a genome scan on 146 nuclear families from Hungary containing an affected proband and affected siblings. In total, the pedigrees contained 303 affected children: 146 probands, 137 siblings with a first episode of mood disorder before 14.9 years of age, and 20 siblings with onset of their first episode after 14.9 years of age but before the age of 18. The results of the genome scan using 405 microsatellite markers did not provide evidence for linkage at the recommended genome wide significance level for any novel loci. However, markers on two chromosomes, 13q and Xq, provided evidence for linkage in regions previously identified as linked to bipolar disorder in multiple studies. For the marker on chromosome 13q the peak non-parametric multipoint LOD score was at the marker D13S779 (LOD = 1.5, P = 0.004). On chromosome Xq, evidence for linkage was observed across a large region spanning two regions previously linked to bipolar disorder; Xq24 to Xq28, with a peak at marker TTTA062 (LOD 2.10, P = 0.0009) in Xq28. Results for these regions exceed the recommended P-value for a replication study of P < 0.01 and thus provide evidence for these two loci as contributing to mood disorders with juvenile onset.

Gender differences in emotional reactivity of depressed and at-risk preschoolers: implications for gender specific manifestations of preschool depression

We investigated whether differences in positive and negative emotional reactivity could be found in depressed preschoolers and preschoolers at risk for later internalizing symptoms relative to nondepressed/low risk comparison groups. Observational measures of emotional reactivity, used to derive a score of the balance between anger and sadness, were obtained and analyzed in independent samples. One study utilized cross-sectional data from preschoolers (M age = 4.6 years) with a current depressive syndrome and two nondepressed comparison groups. The other study utilized longitudinal data that assessed emotional reactivity at preschool age (M age = 4.5 years) and later mental health symptoms during the transition to primary school, allowing a retrospective determination of risk. Depressed and at-risk boys displayed more anger than sadness in contrast to girls in the same groups and in contrast to no disorder/low-risk controls. This finding was detected in depressed and "at risk for internalizing" boys who were not comorbid for externalizing problems.

Attention deficit-hyperactivity disorder and early-onset bipolar disorder: two facets of one entity?

Early-onset bipolar disorder (BD) and attention-deficithyperactivity disorder (ADHD) have recently been the subject of highly controversial debate, due to theories regarding underlying pathophysiological processes and a clinical overlap of symptoms. Epidemiological data, clinical aspect, neuroimaging, neurochemical, and genetic studies suggest that there may be a possible relationship between biological factors and clinical characteristic in the development of symptoms. However, longitudinal data supporting the hypothesis of a diagnostic shift from BD to ADHD symptoms and vice versa are currently not available. These would be essential to enable further investigations into whether these two disorders possibly represent two different aspects of an underlying common psychopathophysioiogical entity.

Accumulation of trauma over time and risk for depression in a twin sample

BACKGROUND

Few genetically informative studies have examined the effects of different types of trauma on risk for depression over time. The aim of the present study was to examine the relative contributions over time of assaultive trauma, non-assaultive trauma, and familial effects to risk for depression.

METHOD

Histories of depression and trauma were obtained during structured diagnostic interviews with 5266 (mean age 29.9 years, s.d.=2.4) members of a volunteer Australian twin panel from the general population. Age at first onset of a DSM-IV major depressive episode was the dependent variable. Associations of depression with traumatic events were examined while accounting for the temporal sequence of trauma and depression and familial effects.

RESULTS

Assaultive traumatic events that occurred during childhood had the strongest association with immediate and long-term risk for depression, and outweighed familial effects on childhood-onset depression for most twins. Although men and women endorsed equal rates of assaultive trauma, women reported a greater accumulation of assaultive events at earlier ages than men, whereas men reported a greater accumulation of non-assaultive events at all ages.

CONCLUSIONS

Early exposure to assaultive trauma can influence risk for depression into adulthood. Concordance for early trauma is a significant contributor to the familiality of early-onset depression.

Pediatric bipolar disorder: validity, phenomenology, and recommendations for diagnosis

OBJECTIVE

To find, review, and critically evaluate evidence pertaining to the phenomenology of pediatric bipolar disorder and its validity as a diagnosis.

METHODS

The present qualitative review summarizes and synthesizes available evidence about the phenomenology of bipolar disorder (BD) in youths, including description of the diagnostic sensitivity and specificity of symptoms, clarification about rates of cycling and mixed states, and discussion about chronic versus episodic presentations of mood dysregulation. The validity of the diagnosis of BD in youths is also evaluated based on traditional criteria including associated demographic characteristics, family environmental features, genetic bases, longitudinal studies of youths at risk of developing BD as well as youths already manifesting symptoms on the bipolar spectrum, treatment studies and pharmacologic dissection, neurobiological findings (including morphological and functional data), and other related laboratory findings. Additional sections review impairment and quality of life, personality and temperamental correlates, the clinical utility of a bipolar diagnosis in youths, and the dimensional versus categorical distinction as it applies to mood disorder in youths.

RESULTS

A schema for diagnosis of BD in youths is developed, including a review of different operational definitions of 'bipolar not otherwise specified.' Principal areas of disagreement appear to include the relative role of elated versus irritable mood in assessment, and also the limits of the extent of the bipolar spectrum--when do definitions become so broad that they are no longer describing 'bipolar' cases?

CONCLUSIONS

In spite of these areas of disagreement, considerable evidence has amassed supporting the validity of the bipolar diagnosis in children and adolescents.

Restoring melancholia in the classification of mood disorders

The present DSM criteria for major depression poorly identify samples for treatment selection, prognosis, and assessments of pathophysiology. Melancholia, in contrast, is a disorder with definable clinical signs that can be verified by laboratory tests and treatment response. It identifies more specific populations than the present system and deserves individual identification in psychiatric classification. Its re-introduction will refine diagnosis, prognosis, treatment selection, and studies of pathophysiology of a large segment of the psychiatrically ill.

Social neuroscience of child and adolescent depression

The social neuroscience of child and adolescent depression is inherently multidisciplinary. Depressive disorders beginning early in life can have serious developmental and functional consequences. Psychopathology research has described depression's defining clinical and contextual features, and intervention research has characterized its response to treatment and prevention programs. Neuroendocrine, electrophysiological, and neuroimaging studies have identified core neurobiological aspects of early-onset mood disorders. These areas are reviewed using a developmental social neuroscience perspective for integrating disparate observations. The paper introduces a dynamic adaptive systems framework, and it discusses hedonic capacity, stress sensitivity, ruminative self-focus, and attentional impairments as fundamental components of mood disorders.

p75(NTR) gene and suicide attempts in young adults with a history of childhood-onset mood disorder

Recently, evidence has accumulated for the role of neurotrophic processes in mood disorders. Neurotrophins operate on receptors, one of which is the p75 neurotrophin receptor (p75(NTR)). We examined three p75(NTR) markers at the p75(NTR) gene, including a missense polymorphism that changes serine to leucine (S205L), for association with suicide attempt (SA) in 203 childhood-onset mood disorder (COMD) cases. There was no difference between COMD suicide attempters and COMD non-attempters with logistic regression models for any of the three markers. We also compared the three polymorphisms between 192 COMD cases and 192 matched healthy controls and found no significant differences between COMD and healthy controls. Our results do not support an association of the p75(NTR) S205L polymorphism with risk for COMD or SA in COMD.

Does bipolar disorder exist in children? A selected review

Although there is increasing recognition that a substantial proportion of patients with bipolar disorder (BD) experience an onset of illness in adolescence, significant controversy remains over the validity of the diagnosis in very young children. In careful studies of adult patients dating from Kraepelin, first mood episodes not uncommonly occurred during adolescence. Some of these early-onset patients experienced subthreshold mood disturbances or predisposing temperaments earlier in childhood. Earlier onsets of BD have been reported in more recent clinical and community samples of children. Several factors possibly contributed to these earlier onsets, including exposure to psychotropics, bias in favour of a mood rather than a psychotic diagnosis, and recognition of softer-spectrum BDs. However, the validity of the diagnosis of BD in impulsive, irritable, labile, or behaviourally dysregulated children remains to be proven. Studies of high-risk children of well-characterized parents with BD have demonstrated that BD most often debuts as a depressive episode in mid to late adolescence and that activated episodes are rare prior to age 12 years. Some children manifest antecedent nonspecific psychopathology in early childhood. Therefore, as currently diagnosed, BD does not manifest as such typically until at least adolescence.

Life stress and the course of early-onset bipolar disorder

BACKGROUND

Studies of adult bipolar patients and adolescents with major depression indicate that life stress and mood symptoms are temporally and causally related to one another. This study examined whether levels of life stress predict levels of mood symptoms among bipolar adolescents participating in a treatment development study of family-focused psychoeducation and pharmacotherapy.

METHODS

Bipolar adolescents (n=38) who reported a period of acute mood symptoms within the prior 3 months were recruited for a 1-year study of life stress. Clinician-administered evaluations were completed with adolescents and parents at 3-month intervals for up to 12 months, using the UCLA Life Stress Interview and the K-SADS Mania and Depression Rating Scales.

RESULTS

Chronic stress in family, romantic and peer relationships was associated with less improvement in mood symptoms over the study year. The frequency of severe, independent life events also predicted less improvement in mood symptoms. Higher levels of chronic stress in family and romantic relationships, and higher severity of independent events, were more strongly associated with mood symptoms among older adolescents. Results were independent of adolescents' psychosocial treatment regimens.

LIMITATIONS

The majority of adolescents received family-focused psychoeducational treatment and all were being treated with psychotropic medication. The influence of life stress on mood symptoms may have been attenuated by intensive intervention.

CONCLUSIONS

Stress is linked to changes in mood symptoms among bipolar adolescents, although correlations between life events and symptoms vary with age. Chronic stress in family, romantic, and peer relationships are important targets for psychosocial intervention.

A strategy for identifying phenotypic subtypes: concordance of symptom dimensions between sibling pairs who met screening criteria for a genetic linkage study of childhood-onset bipolar disorder using the Child Bipolar Questionnaire

BACKGROUND

Specific symptom dimensions have been used to establish phenotypic subgroups in recent genetic studies of bipolar disorder. In preparation for a genetic linkage study of childhood-onset bipolar disorder (COBPD), we conducted an exploratory analysis of the concordance of prominent symptom dimensions between sibling pairs (N=260) who screened positive for COBPD. This report presents data on the potential usefulness of these dimensions in genotyping.

METHOD

A principal components factor analysis was conducted on the symptoms of 2795 children who screened positive for COBPD on the Child Bipolar Questionnaire (CBQ). The resulting factors were used in a concordance analysis between 260 proband/sibling pairs and 260 proband/matched comparison pairs.

RESULTS

Ten factors were extracted. The strongest concordance coefficients (rho) between probands and siblings, and the widest contrasts between proband/sibling vs. proband/comparison pairs, were for Factor 9 (Fear of harm), Factor 5 (Aggression), Factor 10 (Anxiety), Factor 4 (Sensory sensitivity), Factor 6 (Sleep-wake cycle disturbances), and Factor 2 (Attention/Executive function deficits). Based on factor loadings and multivariate analyses, CBQ items were selected for a "Core Index" subscale that had a robust concordance estimate in the sibpair group (rho=0.514, 95% CI 0.450-0.577) as compared to the proband-matched comparison group (rho=0.093, 95% CI 0.008 to 0.178).

LIMITATIONS

Research diagnostic interviews (K-SADS P/L) were conducted to confirm bipolar diagnosis in only a subsample (N=100) of the children whose data were used for the concordance analysis.

CONCLUSIONS

Our data suggest a profile of heritable clinical dimensions in addition to classic mood symptomatology in COBPD. These features may represent a more homogeneous phenotypic subtype of COBPD that may prove more useful for delineating the neurobiology and genetics of the disorder than standard diagnostic models.

Life events and juvenile bipolar disorder: conceptual issues and early findings

There is increasing interest in the psychosocial variables that might predict the course of child and adolescent bipolar disorder. In the literature on adult bipolar disorder, life events have been shown to be a major predictor of symptoms. In this review, we focus on studies of how life events influence the course of child and adolescent bipolar disorder. To begin, we review methodological considerations in life events research, and briefly summarize the findings regarding life events in adult bipolar disorder. Then, we discuss available studies on life events as a predictor of the course of juvenile bipolar disorder. We conclude with suggested directions for future research.

Neurobiology of depression in children and adolescents

This article reviews classical and updated studies of the neurobiology of depressive disorders in children and adolescents. Most studies of childhood and adolescent depression and suicide have followed up the observations and methods used in studies in adults. These studies include neuroendocrine studies, which particularly look at the hypothalamic-pituitary-adrenal axis, the serotonergic system, peripheral blood and cerebrospinal fluid biologic markers, genetics, gene-environment interactions and sleep studies, and neuroimaging and postmortem studies, although in these areas the number of studies is limited.

Twin studies in pediatric depression

Pediatric depression is an important clinical problem that is known to be familial. Twin studies have been used not only to examine the genetic etiology of depression but also to investigate developmental changes and gender effects, the relationship of depression with anxiety, and increasingly, the interplay of genetic liability with environmental risk factors. There is evidence that pediatric depression symptom scores and clinical depression are genetically influenced, but results from different twin studies have varied. These studies also have demonstrated the important contribution of environmental risk factors. Some of the differences in findings may be caused partly by clinical heterogeneity, developmental differences in etiology (stronger genetic influences for depression symptom scores in adolescence than in childhood), and measurement issues, such as who rates the symptoms.

Pilot sample of very early onset bipolar disorder in a military population moderates the association of negative life events and non-fatal suicide attempt

OBJECTIVE

To examine the moderating effects of very early onset diagnostic status (<or= 13 years) upon the association between life events and non-fatal suicide attempt.

METHODS

Measures of negative life events, suicidal ideation and current suicide attempt were administered to 298 military-based young adults at entry to treatment for suicidality. Current and lifetime diagnoses were assigned using the Diagnostic Interview Schedule. The predictive ability of negative life events for non-fatal suicide attempt was examined separately for the total sample and for those with retrospectively determined histories of very early onset bipolar disorder (VEOBPD; n = 16), very early onset major depressive disorder (VEOMDD; n = 21) and very early onset anxiety disorder (VEOANX; n = 53).

RESULTS

Negative life events and suicide attempt were significantly and positively associated among those with no history of VEOBPD (OR = 1.30, 95% CI = 1.02-1.65, p < 0.05), including those with VEOMDD and VEOANX. Consistent with expectation, VEOBPD moderated the association between negative life events and suicide attempt (OR = 0.88, 95% CI = 0.78-0.99, p < 0.05), such that negative life events were non-significantly and negatively associated with the presence of a suicide attempt (OR = 0.21, 95% CI = 0.04-1.02, p = 0.09) among patients with a history of VEOBPD.

CONCLUSIONS

Despite similar rates of suicide attempt among all diagnostic groups, life stress did not contribute to attempt among those with VEOBPD. These findings are consistent with the severity and chronicity of VEOBPD. Potential explanations of these findings include a scarring effect on coping skills and increased sensitization to life stress.

Prepubertal depression: diagnostic and therapeutic dilemmas

Childhood depression is underrecognized. Longitudinal studies have found that depression is a chronic and relapsing disorder in children aged 6 years and older. Now there is evidence that a depressive syndrome can occur in preschool children. Defining depressive syndromes in preschool and elementary-school children has been a challenge. Children should be seen in the context of their social environment (ie, family and peer group) and their larger physical and cultural surroundings. A developmental perspective is important in diagnosing psychopathology in children. Evaluation should include a complete medical assessment to rule out underlying medical causes. A structured clinical interview and rating scales are helpful in determining whether a child or adolescent is depressed. Evidence-based treatment guidelines are limited. The diagnosis of depression in young children remains an active area of debate and study. Clearly more research is needed.

Prediction of change in level of problem behavior among children of bipolar parents

OBJECTIVE

To determine the effects of familial loading, birth weight, and family problems on change in parent-reported problems across a 14-month period among children of bipolar parents.

METHOD

Emotional and behavioral problems in a sample of 140 offspring of bipolar parents and familial loading in first- and second-degree relatives were assessed at two measurements. Parents reported the birth weight of their offspring and completed a questionnaire on family problems. Multiple linear regression analyses were performed to assess associations of the three predictors with change in problem scores at follow-up.

RESULTS

Familial loading of unipolar disorder was a unique predictor for an increase in problem scores from the first to the second measurement with beta-coefficients ranging from 0.17 to 0.25. Birth weight and family problems were not associated with change in problem scores across the two measurements.

CONCLUSION

Familial loading of unipolar disorder predicted an increase in behavioral and emotional problems across the 14-month follow-up.

Family, twin, adoption, and molecular genetic studies of juvenile bipolar disorder

Juvenile bipolar disorder (JBD) has been a subject of significant research and debate. Phenotypic differences between JBD and adult-onset bipolar disorder have led researchers to question whether or not similar neuropathologic mechanisms will be found. While much is known about the genetic and environmental contributions to the adult-onset phenotype, less is known about their contributions to JBD. Here, we review family, twin, adoption, and molecular genetic studies of JBD. Behavioral genetic data suggest both genetic and environmental contributions to JBD, while molecular genetic studies find linkage to age of onset of bipolar disorder to chromosomes 12p, 14q, and 15q. Additionally, changes associated with symptom age of onset have been recently reported in the brain-derived neurotrophic factor (BDNF) and glycogen synthase kinase 3-beta (GSK3-beta) genes. We contend that further progress in discovering the precise genetic and environmental contributions to JBD may depend on advances in phenotypic refinement, an increased appreciation of comorbid conditions, and more investigation of the longitudinal course of the disorder.

Brain-derived neurotrophic factor variants are associated with childhood-onset mood disorder: confirmation in a Hungarian sample

Brain-derived neurotrophic factor (BDNF) is a nerve growth factor that has been implicated in the neurobiology of depression. Our group has previously reported an association between a BDNF variant and childhood-onset mood disorder (COMD) in an adult sample from Pittsburgh. We hypothesize that variants at the BDNF locus are associated with COMD. Six BDNF polymorphisms were genotyped in 258 trios having juvenile probands with childhood-onset DSM-IV major depressive or dysthymic disorder. BDNF markers included the (GT)n microsatellite, Val66Met and four other single-nucleotide polymorphisms (SNPs) distributed across the BDNF gene. Family-based association and evolutionary haplotype analysis methods were used. Analysis of linkage disequilibrium (LD) revealed substantial LD among all six polymorphisms. Analyses of the Val66Met polymorphism demonstrated significant overtransmission of the val allele (chi2=7.12, d.f.=1, P=0.0076). Consistent with the pattern of LD, all other SNPs showed significant biased transmission. The (GT)n microsatellite alleles also indicated a trend towards biased transmission (170 bp: Z=2.095, P=0.036). Significant haplotypes involved Val66Met and BDNF2 (P=0.0029). In this Hungarian sample, we found all five BDNF SNPs tested and a haplotype containing the BDNF Val66Met Val allele to be associated with COMD. These results provide evidence that BDNF variants affect liability to juvenile-onset mood disorders, supported by data from two independent samples.

Stressful life events and onset of mood disorders in children of bipolar parents during 14-month follow-up

BACKGROUND

Although multiple studies have examined the association between stressful life events (SLEs) and the development of mood disorders, the exact nature of the association and the degree to which it is independent from familial loading (FL) and gender-specific are still not fully elucidated.

AIMS

To study the association between person-independent and -dependent SLEs and first onset or recurrence of a DSM-IV mood disorder episode (MDE) in offspring of bipolar parents. To examine interaction effects of SLEs with familial loading and gender.

METHOD

Offspring of bipolar parents (N=132) were assessed with the K-LEDS, the FHRDC and the K-SADS. Logistic regression analysis was used to examine main and interaction effects of various operationalizations of SLEs, familial loading and gender.

RESULTS

Dependent SLEs were more likely to occur before onset among the 13 offspring who had a MDE onset during the 14-month follow-up (39%) than in a comparable period among the 67 controls without any lifetime diagnosis (10%). Associations were slightly stronger for first onsets than for recurrences. The association between SLEs and MDE onset/recurrence was independent of socio-demographic characteristics and familial loading, but disappeared when adjusted for baseline anxious/depressive symptoms. Gender and familial loading did not modify the influence of any SLE measure on the development of mood disorders.

CONCLUSIONS

In this sample of bipolar offspring dependent stressful SLEs triggered the onset of MDEs, but this association disappeared after adjustment of prior anxious/depressive symptoms, indicating that the association between SLEs and MDE is probably a spurious association. No interaction was found between SLE and FL and gender. Prior anxious/depressive symptoms seem to increase the risk for both occurrence of dependent SLEs and MDE onset or recurrence.

LIMITATIONS

Limited statistical power due to small number of MDE onsets.

Association of parental depression with psychiatric course from adolescence to young adulthood among formerly depressed individuals

The authors examined whether parental major depressive disorder (MDD) is associated with course of depression and other psychopathology among formerly depressed adolescents as they enter adulthood. The sample consisted of 244 individuals (age 24) in a longitudinal study who had experienced MDD by 19. Maternal MDD was associated with MDD recurrence, chronicity and severity, anxiety disorders, and (among sons only) lower psychosocial functioning in offspring between the ages of 19 and 24. Paternal MDD was associated with lower functioning. Sons of depressed fathers had elevated suicidal ideation and attempt rates in young adulthood. Recurrent paternal MDD was associated with depression recurrence in daughters but not sons. The impact of parental MDD on offspring could not be attributed to characteristics of the offspring's depression prior to age 19.

Mediating links between maternal depression and offspring psychopathology: the importance of independent data

BACKGROUND

Research examining intergenerational transmission of psychopathology is often limited by reliance on the same individuals for information on multiple constructs of interest. To counteract this limitation, data from a prospective, longitudinal study of at-risk youth were analyzed to test the hypothesis that parenting and family environmental factors mediate the association between maternal depressive symptoms and offspring psychopathology in late adolescence.

METHOD

Data were taken from 184 families of the Minnesota Longitudinal Study of Parents and Children. Measures included the CES-D and Beck depression inventories, home environment ratings and a family conflict scale, and CBCL behavior problem checklist and K-SADS psychiatric symptom scores. Regression analyses were conducted to test for mediation of maternal depression effects by family environmental factors.

RESULTS

Analyses using a single informant and time point showed evidence for substantial mediation; however, in analyses spanning independent informants and multiple time points mediating effects were markedly reduced. Sex differences were found, in that parenting and family environmental factors related to psychopathology for males, whereas maternal depression was more directly related to psychopathology for females.

CONCLUSIONS

Results emphasize the importance of independent data for testing mediational claims, and support claims that the processes involved in the intergenerational transmission of psychopathology are different for male and female youth.

Age at onset in bipolar affective disorders: a review

Bipolar affective disorder (BPAD) is a multifactorial disorder with various clinical presentations. Etiologic heterogeneity may partly underlie the phenotypic heterogeneity. Efforts to dissect BPAD have been based on the course of the disorders (BP I versus BP II or rapid cycling), comorbidity pattern (panic attacks, suicide attempts, addiction or hyperactivity), differences between the sexes, and clinical pattern (cycloid and puerperal psychosis). The present article provides a comprehensive review of the existing data, showing that age at onset (AAO) identifies homogeneous sub-groups of patients with BPAD. Recent work has demonstrated the existence of three--early, intermediate and late--onset bipolar sub-groups based on AAO, following Kendell's criteria for validity (The American Journal of Psychiatry 2003; 160: 999). We will also show how these distinctions may be of use in the search for genetic vulnerability factors and other pathogenic influences. Following Kendell's criteria, we show that AAO of bipolar disorders has been tested with most of the available strategies for establishing the validity of clinical syndromes. We also present data from genetic epidemiologic studies in bipolar disorder, showing that AAO sub-groups may reduce the underlying genetic heterogeneity. No accurate AAO thresholds to define valid sub-groups have been identified precisely. Until recently, studies defined early- and late-onset as corresponding to early or mid-adulthood, not taking into account juvenile-onset bipolar disorder. A recently proposed theoretical model with three AAO sub-groups (onset age 17, 27 and 46) is discussed.

Association study of neurotrophic tyrosine kinase receptor type 2 (NTRK2) and childhood-onset mood disorders

Childhood-onset mood disorders (COMD) are often familial, and twin studies of COMD provide compelling evidence that genetic factors are involved. Deficits in neural plasticity have been suggested to underlie the development of depression. The receptor tropomyosin related kinase B (TrkB) and its ligand, brain derived neurotrophic factor (BDNF), play essential roles in neural plasticity, and mRNA expression of both of these genes has been shown to be influenced by stress and chronic antidepressant treatment. In addition, TrkB knock-out mice display inappropriate stress coping mechanisms. Having previously shown that BDNF is associated with COMD, in this study we investigated the gene encoding TrkB, neurotrophic tyrosine kinase, receptor, type 2 (NTRK2) as a susceptibility factor in COMD. We tested for association of NTRK2 with COMD in two independent samples: (a) a case-control sample matched on ethnicity and gender, consisting of 120 cases who met DSM III/IV criteria for major depressive or dysthymic disorder before age 14 or bipolar I/II before the age of 18, and controls, and (b) a family based control sample of 113 families collected in Hungary, identified by a proband between the age of 7 and 14 who met DSM IV criteria for major depressive disorder or bipolar I/II disorder. There was no evidence for an allelic or genotypic association of three polymorphisms of NTRK2 with COMD in the case-control sample. Also, in the family based sample, using the transmission disequilibrium test (TDT), we did not identify any evidence of allelic association for each marker individually or when haplotypes were analyzed. Based on these results, using these three polymorphisms, we do not find support for NTRK2 as a susceptibility gene for COMD.

Amygdala and hippocampus volumes in pediatric major depression

BACKGROUND

The purpose of this study was to measure amygdala and hippocampus volumes in pediatric major depressive disorder (MDD) and to address the question of neuroanatomical continuity with adult-onset depression.

METHODS

We studied 20 children and adolescents with MDD (17 female subjects) and 24 healthy comparison subjects (16 female subjects) using 1.5 Tesla magnetic resonance imaging. Group differences in left and right amygdala and hippocampus volumes were examined using repeated measures analyses of covariance, adjusting for age, gender, and whole brain volume.

RESULTS

Depressed children had significant reductions of left and right amygdala volumes compared with healthy subjects. Hippocampus volumes did not differ between the groups. No significant correlations were found between amygdala volumes and depressive symptom severity, age at onset, or illness duration.

CONCLUSIONS

Smaller amygdalas are present early in the course of pediatric depression and may predispose to the development of this disorder or perhaps more generally of childhood mood disorders. Future research should examine the longitudinal course and functional correlates of amygdala volume abnormalities in childhood-onset depression, including their possible moderation by gender.

A prospective follow-up study of pediatric bipolar disorder in boys with attention-deficit/hyperactivity disorder

OBJECTIVE

To examine patterns of persistence and remission in pediatric bipolar disorder attending to syndromatic, symptomatic, functional and affective definitions of remission of bipolar symptomatology in a longitudinal sample of ADHD children with comorbid bipolar disorder.

METHODS

ADHD boys (128) were followed over 1- and 4-year follow-up assessments with structured diagnostic interviews to assess the persistence of psychiatric comorbidity. The course and duration of bipolar disorder was estimated by calculating the time from age at onset and the age at remission reported at either the 1- or 4-year follow-up assessments.

RESULTS

Twenty-two (17%, Prevalent Cases) subjects met criteria for bipolar disorder at the baseline assessment. The average age of these subjects was 10.5+/-3.0 (range: 6 to 17 years) at baseline and 14.4+/-3.1 years of age at follow-up. The rate of remission was heavily dependent on the definition used. The rate of functional remission was the lowest and the rate of syndromatic remission was the highest. Regardless of the definition used, however, the disorder was chronic and lasted many years.

LIMITATIONS

These data should be considered preliminary due to the sample size and the absence of mood symptom rating scales.

CONCLUSIONS

That less than 20% of subjects attained functional remission or euthymia over the entire time period evaluated provides further evidence that pediatric bipolar disorder is a chronic mood disorder with a poor prognosis.

A case-control and family-based association study of the 5-HTTLPR in pediatric-onset depressive disorders

BACKGROUND

Pediatric depression can be particularly informative for clarification of the causes of mood disorders. The aim of this work was to explore the possible association between childhood- and early-adolescent-onset DSM-IV depressive disorders (DD; including major depression and dysthymia) and the serotonin transporter-linked promoter polymorphism (5-HTTLPR) locus.

METHODS

The case-control sample consisted of 68 unrelated patients with DD, and 68 unrelated age- and gender-matched healthy control subjects. The same patients were included in the family-based study, which consisted of 41 triads and 11 dyads.

RESULTS

An excess of the SS-genotype (p =.025) and of the S-allele (p =.021) was found among DD children (odds ratio = 1.81; 95% confidence interval = 1.12-2.94). The family-based results suggested that the S-allele was preferentially transmitted to depressed children (haplotype-based haplotype relative risk: chi(2) = 7.231 df = 1, p =.007; transmission disequilibrium test: chi(2) = 5.233, df = 1, p =.022).

CONCLUSIONS

A role for the 5-HTTLPR locus that needs replication in larger samples is suggested in childhood DD.

Multiple dimensions of familial psychopathology affect risk of mood disorder in children of bipolar parents

The aim of our study was to determine whether familial loading of unipolar disorder, bipolar disorder, and substance use disorder are associated with DSM-IV mood disorders in adolescents at risk for bipolar disorder. One hundred and forty adolescents aged 12-21 years of 86 bipolar parents participated in the study. Lifetime DSM-IV diagnoses of the bipolar offspring were assessed with the Schedule for Affective Disorders and Schizophrenia for School Age Children Kiddie-SADS-Present and Lifetime Version (SADS-PL). Parents were interviewed using the Family History Research Diagnostic Criteria (FH-RDC) which were used to calculate a continuous familial loading score (FL) for unipolar disorder, bipolar disorder, and for substance use disorder in first- and second-degree relatives of the adolescents. FL for unipolar disorder and substance use disorder were strong and independent predictors for lifetime mood disorders in the adolescents. The gender adjusted hazard ratios for mood disorders in the children were 1.5 (95% confidence interval (CI) = 1.2-2.0) for FL of unipolar disorder and 1.8 (95% CI = 1.3-2.4) for FL of substance use disorder. Expression of mood disorders in children of bipolar parents varies with the degree of additional FL of unipolar disorder and substance use disorder in the extended family.

Defining a developmental subtype of bipolar disorder in a sample of nonreferred adults by age at onset

OBJECTIVE

To test the hypothesis that the age at onset of bipolar disorder would identify a developmental subtype of bipolar disorder in adults characterized by increased levels of irritability, chronic course, rapid cycling, and comorbidity with attention deficit hyperactivity disorder.

METHODS

Forty-four adult subjects diagnosed with bipolar disorder were selected from large family studies of youth with and without attention deficit hyperactivity disorder. These subjects were stratified by the age at onset in childhood (younger than 13 years; n = 8, 18%), adolescence (13-18 years; n = 12, 27%, or adulthood (older than 19 years; n = 24, 55%). All subjects were administered structure diagnostic interviews and a brief cognitive battery.

RESULTS

In contrast with adult-onset bipolar disorder, child-onset bipolar disorder was associated with a longer duration of illness, more irritability than euphoria, a mixed presentation, a more chronic or rapid-cycling course, and increased comorbidity with childhood disruptive behavior disorders and anxiety disorders.

CONCLUSION

Stratification by age at onset of bipolar disorder identified subgroups of adult subjects with differing clinical correlates. This pattern of correlates is consistent with findings documented in children with pediatric bipolar disorder and supports the hypothesis that child-onset bipolar disorder may represent a developmental subtype of the disorder.

Nonsomatic treatment of depression

Clinicians who treat depressed children and adolescents are faced with substantial challenges. Although to date the results of controlled psychotherapy trials with depressed youths offer limited guidance regarding choice of treatment, some general guidelines can be culled from the available data. Interventions or elements of therapies that are structured and directed towards cognitive behavioral or relationship issues show promise for the treatment of juvenile depression. Group interventions seem to be as effective as the more traditional individual therapy. Parental participation in empiric treatment trials of pediatric depression has been limited to either separate parent groups as an adjunct or to family therapy,but for various practical and clinical reasons it may be wise to involve parents directly. Parents may be critical to the success of interventions with depressed children and should be regarded as potentially important agents of change.

First episode of depression in children at low and high familial risk for depression

OBJECTIVE

To examine the development of first-onset major depressive disorder (MDD) in children at high and low familial risk for depression in a prospective study.

METHOD

High-risk children (n = 76) who were free of any lifetime affective disorder and had at least one first-degree and one second-degree relative with a lifetime history of childhood-onset, recurrent, bipolar, or psychotic depression were included. Low-risk children (n = 63) were included if they were free of any lifetime psychiatric disorder and had no first-degree relatives and fewer than 20% of their second-degree relatives with a lifetime affective disorder. Children and their parents were assessed in a prospective design using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Epidemiologic version (K-SADS-E). The average interval between follow-up interviews was 18 months, and the average follow-up period was 6 years.

RESULTS

High-risk children had approximately a threefold increased risk of developing first-onset MDD compared with low-risk children (odds ratio = 3.21). The average age of new-onset MDD was 14.0 +/- 2.9 years (range 9.5-19.5 years). Above and beyond the familial loading for MDD, mother's lifetime anxiety disorder (odds ratio = 2.84) and lifetime behavioral disorder (odds ratio = 3.25) in the child significantly added to the risk of developing a first-onset MDD.

CONCLUSIONS

Having high familial loading for affective disorders, a mother with and anxiety disorder, and a behavioral disorder in the child all significantly contributed to the risk of developing depression.

Early-onset depression and the emotional and behavioral characteristics of offspring

We compared the emotional and behavioral characteristics of offspring of parents with early-onset depression and the offspring of parents with late-onset depression. Forty-three parents who met criteria for major depressive disorder (MDD) completed the Achenbach Child Behavior Checklist-Parent Report Version (CBCL) for a birth child (n=43, age range 6-17 years). Parents were classified as having either early SD onset (<19 years) or late-onset (> or = 19 years) MDD based on responses gathered during the SCID-P interview. Unpaired t-tests were used to compare the two offspring groups on CBCL clinical and competency scales. Chi-square analyses and unpaired t-tests were used to compare the two parent groups on demographic and clinical features. Offspring of parents with early-onset depression scored significantly higher on the majority of the CBCL clinical scale scores when compared with offspring of parents with late-onset depression, rated as exhibiting higher levels of the characteristics measured: withdrawn, anxious/depressed, social problems, thought problems, attention problems, delinquent behavior, and aggressive behavior. Additionally, this group had a significantly higher total T score (a global measure of psychopathology) and significantly lower social functioning. Children of parents with early-onset depression may be at higher risk for behavioral and emotional problems than offspring of parents with late-onset depression. This finding may be significant in uncovering sources of vulnerability and formulating intervention strategies for offspring of depressed parents.

Preschool outcomes of children of depressed mothers: role of maternal behavior, contextual risk, and children's brain activity

Children of depressed mothers are at risk for behavioral and emotional problems. Infants of depressed mothers exhibit behavioral disturbances and atypical frontal brain activity. The mechanisms by which children develop such vulnerabilities are not clear. Three-year-old children of mothers with (N = 65) and without (N = 59) a history of depression were assessed in terms of behavior problems and brain electrical activity. Children of mothers with chronic depression exhibited lower frontal and parietal brain activation compared with children of mothers without depression and those whose depression remitted. Depressed mothers reported higher contextual risk (e.g., marital discord and stress) and their children had more behavior problems. Children's frontal brain activation and contextual risk level mediated the relation between maternal depression and child behavior problems.

Is preadolescent mania the same condition as adult mania? A British perspective

Until relatively recently, the prevailing view was that mania was uncommon in preadolescent children. In the past 15 years, however, there has been increasing interest in the idea that mania may be much more common at younger ages than previously recognized. This article is concerned with the issue of whether preadolescent mania represents the same kind of problem as adult mania. It reviews concepts of bipolar disorder and mania in adults and preadolescents, some of the issue that arise in diagnosing mania in children, and the evidence for continuities between preadolescent and adult mania. The diagnosis of mania in preadolescent children often requires that inferences are made about the meaning of some symptoms but it is not always clear that these inferences are valid. It is concluded that the extant evidence does not provide a clear conclusion about the links between preadolescent and adult mania. More work is needed on the phenomenology and diagnosis of mania in children, on its natural history and on its familial correlates.

The genetics of pediatric-onset bipolar disorder

Although bipolar disorder in adults has been extensively studied, early-onset forms of the disorder have received less attention. We review several lines of evidence indicating that pediatric- and early adolescent-onset bipolar disorder cases may prove the most useful for identifying susceptibility genes. Family studies have consistently found a higher rate of bipolar disorder among the relatives of early-onset bipolar disorder patients than in relatives of later-onset cases, which supports the notion of a larger genetic contribution to the early-onset cases. Comorbid pediatric bipolar disorder and attention-deficit/hyperactivity disorder (ADHD) may also define a familial subtype of ADHD or bipolar disorder that is strongly influenced by genetic factors and may, therefore, be useful in molecular genetic studies. There are no twin and adoption studies of pediatric bipolar disorder, but the heritability of this subtype is expected to be high given the results from family studies. Thus, pediatric- and early adolescent-onset bipolar disorder may represent a genetically loaded and homogeneous subtype of bipolar disorder, which, if used in genetic linkage and association studies, should increase power to detect risk loci and alleles.