Heritability of major depressive and comorbid anxiety disorders in multi-generational families at high risk for depression

Heritability and polygenic load for comorbid anxiety and depression

Anxiety and depression commonly occur together resulting in worse health outcomes than when they occur in isolation. We aimed to determine whether the genetic liability for comorbid anxiety and depression was greater than when anxiety or depression occurred alone. Data from 12,792 genotyped twins (ages 38-85) were analysed, including 1,986 complete monozygotic and 1,594 complete dizygotic pairs. Outcomes were prescription of antidepressant and anxiolytic drugs, as defined by the World Health Organization Anatomical Therapeutic Chemical Classification System (ATC) convention, for comorbid anxiety and depression (n = 1028), anxiety only (n = 718), and depression only (n = 484). Heritability of each outcome was estimated using twin modelling, and the influence of common genetic variation was assessed from polygenic scores (PGS) for depressive symptoms, anxiety, and 40 other traits. Heritability of comorbid anxiety and depression was 79% compared with 41% for anxiety and 50% for depression alone. The PGS for depressive symptoms likewise predicted more variation in comorbid anxiety and depression (adjusted odds ratio per SD PGS = 1.53, 95% CI = 1.43-1.63; ΔR2 = 0.031, ΔAUC = 0.044) than the other outcomes, with nearly identical results when comorbid anxiety and depression was defined by International Classification of Diseases (ICD) diagnoses (adjusted odds ratio per SD PGS = 1.70, 95% CI = 1.53-1.90; ΔR2 = 0.036, ΔAUC = 0.051). Individuals in the highest decile of PGS for depressive symptoms had over 5 times higher odds of being prescribed medication for comorbid anxiety and depression compared to those in the lowest decile. While results on a predominant role of depressive symptoms may have been biased by the size and heterogeneity of available data bases, they are consistent with the conclusion that genetic factors explain substantially more variation in comorbid anxiety and depression than anxiety or depression alone.

The genetics of severe depression

Genome-wide association studies (GWASs) of major depressive disorder (MDD) have recently achieved extremely large sample sizes and yielded substantial numbers of genome-wide significant loci. Because of the approach to ascertainment and assessment in many of these studies, some of these loci appear to be associated with dysphoria rather than with MDD, potentially decreasing the clinical relevance of the findings. An alternative approach to MDD GWAS is to focus on the most severe forms of MDD, with the hope that this will enrich for loci of larger effect, rendering their identification plausible, and providing potentially more clinically actionable findings. Here we review the genetics of severe depression by using clinical markers of severity including: age of onset, recurrence, degree of impairment, and treatment with ECT. There is evidence for increased family-based and Single Nucleotide Polymorphism (SNP)-based estimates of heritability in recurrent and early-onset illness as well as severe functional impariment. GWAS have been performed looking at severe forms of MDD and a few genome-wide loci have been identified. Several whole exome sequencing studies have also been performed, identifying associated rare variants. Although these findings have not yet been rigorously replicated, the elevated heritability seen in severe MDD phenotypes suggests the value of pursuing additional genome-wide interrogation of samples from this population. The challenge now is generating a cohort of adequate size with consistent phenotyping that will allow for careful and robust classifications and distinctions to be made. We are currently pursuing such a strategy in our 50-site worldwide Gen-ECT-ics consortium.

Nutritional Strategies in Major Depression Disorder: From Ketogenic Diet to Modulation of the Microbiota-Gut-Brain Axis

Major depressive disorder (MDD) is a leading cause of disability worldwide. While traditional pharmacological treatments are effective for many cases, a significant proportion of patients do not achieve full remission or experience side effects. Nutritional interventions hold promise as an alternative or adjunctive approach, especially for treatment-resistant depression. This review examines the potential role of nutrition in managing MDD through addressing biological deficits and modulating pathways relevant to its pathophysiology. Specifically, it explores the ketogenic diet and gut microbiome modulation through various methods, including probiotics, prebiotics, synbiotics, postbiotics, and fecal microbiota transplantation. Numerous studies link dietary inadequacies to increased MDD risk and deficiencies in nutrients like omega-3 s, vitamins D and B, magnesium, and zinc. These deficiencies impact neurotransmitters, inflammation, and other biological factors in MDD. The gut-brain axis also regulates mood, stress response, and immunity, and disruptions are implicated in MDD. While medications aid acute symptoms, nutritional strategies may improve long-term outcomes by preventing relapse and promoting sustained remission. This comprehensive review aims to provide insights into nutrition's multifaceted relationship with MDD and its potential for developing more effective integrated treatment approaches.

Parental psychopathology and posttraumatic stress in Puerto Ricans: the role of childhood adversity and parenting practices

BACKGROUND

Parental psychopathology is associated with their children's posttraumatic stress symptoms (PTSS). However, the mechanisms through which this occurs remain unclear. We hypothesized that exposure to childhood adversities is the mechanism linking parental psychopathology to child PTSS and that parenting practices moderated these associations.

METHODS

Participants (N = 1,402) with an average age of 24.03 years old (SD = 2.20), were all Puerto Ricans (50% Male and 50% Female) from the Boricua Youth Study, which is a four-wave longitudinal study spanning almost 20 years, following individuals from childhood (ages 5-13 at Wave 1) to young adulthood. Measured variables include parental psychopathology at Wave 1, childhood adversities and parenting practices at Waves 2-3, and PTSS at Wave 4. A traditional mediation model estimated the association between parental psychopathology and child PTSS via childhood adversities. A moderated mediation model was used to examine whether parenting practices moderated this mediation model.

RESULTS

Results showed that the total effect of parental psychopathology at Wave 1 on PTSS at Wave 4 was fully mediated by childhood adversities at Waves 2-3 (direct effect b = 1.72, 95% CI = [-0.09, 3.83]; indirect effect b = 0.40, 95% CI = [0.15, 0.81]). In addition, the magnitude of this pathway varied by levels of parenting practices (i.e. parental monitoring and parent-child relationship quality). Specifically, the indirect effect of additional adversities in the psychopathology-PTSS link was stronger with higher levels of parental monitoring but weaker with higher parent-child relationship quality scores.

CONCLUSIONS

Intergenerational continuity of psychopathology may be mitigated through the prevention of additional childhood adversities via upstream interventions, emphasizing providing parents with mental health needs with parenting tools. Family-based interventions focused on providing families with the tools to improve parent-child relationships may reduce the negative impact of childhood adversities on mental health across the life course.

Associations of adolescent substance use and depressive symptoms with adult major depressive disorder in the United States: NSDUH 2016-2019

BACKGROUND

Few studies have focused on the associations of adolescent substance use and depressive symptoms with adult major depressive disorder (MDD).

METHODS

Data from 168,859 adults, among which, 15,959 had experienced MDD in the past year, as indicated by a major depressive episode (MDE) marked by MDD symptoms, were from the 2016-2019 National Surveys on Drug Use and Health. Weighted multivariable logistic regression (MLR) analyses were used to determine the associations.

RESULTS

The overall MDD prevalence was 7.2 %, whereas the prevalence for adults without early onset depressive symptoms prior to age 18 was 4.6 %. Variable cluster analysis revealed that adolescent use of alcohol, cigarettes, marijuana, cocaine, hallucinogen use, and inhalants prior to age 18 were in one cluster. MLR analyses showed that the presence of depressive symptoms prior to age 18 was the major risk factor for MDD, while adolescent use of alcohol, marijuana, and inhalants prior to age 18 were associated with increased odds of MDD (p < 0.05) both in the whole data and the subset of adults without depressive symptoms prior to age 18. Adolescent use of cocaine prior to age 18 were associated with MDD only in the whole data, whereas adolescent smokeless tobacco use was associated with MDD only in those without depressive symptoms prior to age 18.

CONCLUSIONS

These findings highlight the comorbid early substance use and depressive symptoms during adolescence with adult MDD. Intervention strategies should simultaneously address early-onset substance use and depressive symptoms prior to age 18.

The gut-brain vascular axis in neuroinflammation

The multifaceted microbiota characterizing our gut plays a crucial role in maintaining immune, metabolic and tissue homeostasis of the intestine as well as of distal organs, including the central nervous system. Microbial dysbiosis is reported in several inflammatory intestinal diseases characterized by the impairment of the gut epithelial and vascular barriers, defined as leaky gut, and it is reported as a potential danger condition associated with the development of metabolic, inflammatory and neurodegenerative diseases. Recently, we pointed out the strict connection between the gut and the brain via a novel vascular axis. Here we want to deepen our knowledge on the gut-brain axis, with particular emphasis on the connection between microbial dysbiosis, leaky gut, cerebral and gut vascular barriers, and neurodegenerative diseases. The firm association between microbial dysbiosis and impairment of the vascular gut-brain axis will be summarized in the context of protection, amelioration or boosting of Alzheimer, Parkinson, Major depressive and Anxiety disorders. Understanding the relationship between disease pathophysiology, mucosal barrier function and host-microbe interaction will foster the use of the microbiome as biomarker for health and disease as well as a target for therapeutic and nutritional advances.

Correlates and consequences of anxiety and depressive symptom trajectories during early treatment for alcohol use

We investigated whether latent trajectories of anxiety and depressive symptoms were associated with clinically relevant variables including treatment attrition among individuals seeking treatment for alcohol use. Participants were drawn from 78 addiction treatment centers and included individuals in treatment for alcohol use, had in-treatment data, and screened positive for anxiety (n = 6147) or depressive symptoms (n = 6197) at intake. Anxiety and depressive symptoms were measured weekly during the first month of treatment. Three trajectories of anxiety symptoms (i.e., Persistent Moderate Anxiety Symptoms, Remitting Moderate Anxiety Symptoms, and Remitting Mild Anxiety Symptoms) and depressive symptoms (i.e., Increasing Moderate Depressive Symptoms, Persistent Moderate Depressive Symptoms, and Remitting Mild Depressive Symptoms) were identified. Women, younger individuals, and individuals who endorsed greater past month benzodiazepine use and depressive symptoms at intake were more likely to be in the Persistent Moderate Anxiety Symptoms trajectory relative to the Remitting Mild Anxiety Symptoms subgroup. Women, individuals who screened positive for anxiety at intake, and individuals reporting past month heroin use were more likely to be in the Increasing Moderate Depressive Symptoms trajectory relative to the Remitting Mild Depressive Symptom trajectory. Trajectories characterized by persistent moderate anxiety and depressive symptoms during the first month of treatment were more likely to drop out of treatment compared to individuals who reported low symptom levels. Findings indicate heterogeneity in the clinical course of anxiety and depressive symptoms among individuals in treatment for alcohol use and highlight that persistently high anxiety and depressive symptoms may pose an impediment to successful treatment completion. Results also demonstrate the importance of considering demographic and clinical characteristics at treatment intake as they may have significant implications for the unfolding of anxiety and depressive symptoms during treatment and subsequent outcomes.

Polygenic Risk for Schizophrenia, Major Depression, and Post-traumatic Stress Disorder and Hippocampal Subregion Volumes in Middle Childhood

Studies demonstrate that individuals with diagnoses for Major Depressive Disorder (MDD), Post-traumatic Stress Disorder (PTSD), and Schizophrenia (SCZ) may exhibit smaller hippocampal gray matter relative to otherwise healthy controls, although the effect sizes vary in each disorder. Existing work suggests that hippocampal abnormalities in each disorder may be attributable to genetic liability and/or environmental variables. The following study uses baseline data from the Adolescent Brain and Cognitive Development[Formula: see text] Study (ABCD Study[Formula: see text]) to address three open questions regarding the relationship between genetic risk for each disorder and hippocampal volume reductions: (a) whether polygenic risk scores (PGRS) for MDD, PTSD, and SCZ are related to hippocampal volume; (b) whether PGRS for MDD, PTSD, and SCZ are differentially related to specific hippocampal subregions along the longitudinal axis; and (c) whether the association between PGRS for MDD, PTSD, and SCZ and hippocampal volume is moderated by sex and/or environmental adversity. In short, we did not find associations between PGRS for MDD, PTSD, and SCZ to be significantly related to any hippocampal subregion volumes. Furthermore, neither sex nor enviornmental adversity significantly moderated these associations. Our study provides an important null finding on the relationship genetic risk for MDD, PTSD, and SCZ to measures of hippocampal volume.

Genomic analysis of firework fear and noise reactivity in standard poodles

BACKGROUND

Fear of firework noises and other loud, sudden noises (noise reactivity) is a significant problem for many dogs and may have a negative effect on both welfare and, in severe cases, the life expectancy of dogs. A wide range of behavior traits, including fear-related behaviors, have high heritability estimates in dogs. The aim of this study was to estimate genomic heritability for fear of fireworks and loud noises in dogs.

RESULTS

A genomic heritability estimate was performed based on genome-wide SNPs from standard poodles with records of fear of fireworks and noise reactivity. The study was based on questionnaires answered by owners, who also volunteered to return a cheek swab from their dog for DNA analyses. SNP-based heritability was estimated to be 0.28 for firework fear and 0.16 for noise reactivity. We also identified an interesting region on chromosome 17 that was weakly associated with both traits.

CONCLUSIONS

We have estimated low to medium genomic heritabilities for fear of fireworks and noise reactivity in standard poodles. We have also identified an interesting region on chromosome 17, which harbors genes that have been shown to be involved in different psychiatric traits with anxiety components in humans. The region was associated with both traits; however, the association was weak and need further verification from other studies.

Pursuing the epidemiology and familial risks of depression and developing an evidence based psychotherapy

This commentary, as requested, presents the highlights of my research career. The epidemiology of psychiatric disorders study, challenged in a small study, the notion that diagnosis for psychiatric disorders could be made in a community survey. This pilot study was the basis for the Epidemiology Catchment Area Study (ECA) with 18,000 participants and the many more updated surveys, which followed. The families at High and Low Risk for Depression study in its 40th year challenged the notion that children didn't get depressed and showed that parental depression was the major risk for depression, which began in youth and reoccurred over the lifespan. Interpersonal psychotherapy (IPT), now has been tested in over 150 clinical trials, recommended by the World Health Organization (WHO), globally in China, Germany, Ukraine, and many more countries.

Familial co-aggregation and shared heritability between depression, anxiety, obesity and substance use

Depression, anxiety, obesity and substance use are heritable and often co-occur. However, the mechanisms underlying this co-occurrence are not fully understood. We estimated their familial aggregation and co-aggregation as well as heritabilities and genetic correlations to improve etiological understanding. Data came from the multi-generational population-based Lifelines Cohort Study (n = 162,439). Current depression and anxiety were determined using the MINI International Neuropsychiatric Interview. Smoking, alcohol and drug use were assessed by self-report questionnaires. Body mass index (BMI) and obesity were calculated by measured height and weight. Modified Cox proportional hazards models estimated recurrence risk ratios (λ_R), and restricted maximum likelihood variance decomposition methods estimated heritabilities (h²) and genetic correlations (r_G). All analyses were adjusted for age, age², and sex. Depression, anxiety, obesity and substance use aggregated within families (λ_{R first-degree relative} = 1.08-2.74) as well as between spouses (λ_R = 1.11-6.60). All phenotypes were moderately heritable (from h²_depression = 0.25 to h²_BMI = 0.53). Depression, anxiety, obesity and smoking showed positive familial co-aggregation. That is, each of these traits confers increased risk on the other ones within families, consistent with the positive genetic correlations between these phenotypes (r_G = 0.16-0.94). The exception was obesity, which showed a negative co-aggregation with alcohol and drug use and vice versa, consistent with the negative genetic correlations of BMI with alcohol (r_G = -0.14) and soft drug use (r_G = -0.10). Patterns of cross-phenotype recurrence risk highlight the co-occurrence among depression, anxiety, obesity and substance use within families. Patterns of genetic overlap between these phenotypes provide clues to uncovering the mechanisms underlying familial co-aggregation.

Eveningness increases risks for depressive and anxiety symptoms and hospital treatments mediated by insufficient sleep in a population-based study of 18,039 adults

BACKGROUND

Epidemiological data show that having the eveningness associates with poor mental health. For preventive measures it is important to know which underlying factors mediate these associations and the burden posed to public health. This study examines at a population-based level, whether (1) circadian type and the sleep-wake behavior-based phase entrainment similarly associate with mental health problems, (2) there are differences in hospital treatments due to mental disorders between chronotypes, and (3) the association of chronotype with mental health is mediated by insufficient sleep.

METHODS

The study sample (N = 18,039) consisted of population-based sample of Finnish adults, aged 25-74 years, with information on their circadian type and sleep patterns, mental health symptoms, and diagnosis as reported in a health examination survey, as well as hospital treatments as recorded on the national Hospital Discharge Register.

RESULTS

All the mental health symptoms, diagnoses and hospital treatments were more pronounced among Evening-types, especially when assessed by circadian type. Insufficient sleep mediated most but not all of the associations between eveningness and mental health.

CONCLUSIONS

Eveningness does not increase mental health risks only on symptom or diagnosis level, but also on hospital admission level. A higher prevalence of insufficient sleep among the Evening-types elevates the risk and severity for many of the mental health outcomes. Improving the sleep among Evening-types could help to improve their mental health prospective and ease the health care burden.

Psychiatry in the Digital Age: A Blessing or a Curse?

Social distancing and the shortage of healthcare professionals during the COVID-19 pandemic, the impact of population aging on the healthcare system, as well as the rapid pace of digital innovation are catalyzing the development and implementation of new technologies and digital services in psychiatry. Is this transformation a blessing or a curse for psychiatry? To answer this question, we conducted a literature review covering a broad range of new technologies and eHealth services, including telepsychiatry; computer-, internet-, and app-based cognitive behavioral therapy; virtual reality; digital applied games; a digital medicine system; omics; neuroimaging; machine learning; precision psychiatry; clinical decision support; electronic health records; physician charting; digital language translators; and online mental health resources for patients. We found that eHealth services provide effective, scalable, and cost-efficient options for the treatment of people with limited or no access to mental health care. This review highlights innovative technologies spearheading the way to more effective and safer treatments. We identified artificially intelligent tools that relieve physicians from routine tasks, allowing them to focus on collaborative doctor-patient relationships. The transformation of traditional clinics into digital ones is outlined, and the challenges associated with the successful deployment of digitalization in psychiatry are highlighted.

The role of stressful life events appraisal in major depressive disorder

INTRODUCTION

Major depressive disorder (MDD) is a multifactorial disease in which, due to the interaction of several variables, the vulnerability of suffering from it increases. Several models, such as the diathesis-stress model, have explained these interactions. However, experiencing stressful events does not always lead to the development of MDD, and the attribution and appraisal of stressful events contributing to further development of depression symptoms has been considered as a possible explanation.

OBJECTIVE

To determinate the association and the predictive power of the frequency and appraisal of stressful life events to predict MDD symptomatology.

METHODS

Case-control study with 120 psychiatric patients and 120 people from the general population. A structured clinical interview and the life events questionnaire (Sandín and Chorcot) were used to evaluate the sample. The data were analysed with non-parametric tests and binary logistic regression.

RESULTS

The psychiatric patients reported significantly higher levels of negative affect, frequency of stressful life events, perceived stress, negative appraisal of the situation and lack of perceived control. The binary logistic regression model indicated that poor perception of control of the stressful event is the most determining factor, followed by negative evaluation of the situation.

CONCLUSIONS

The attributions that are made regarding a stressful event are variables that predict MDD, specifically the assessment of the perceived control over the situation. These results concur with the aetiological models of MDD, such as the cognitive diathesis-stress model.

Psychosocial working conditions and depressive disorder: disentangling effects of job control from socioeconomic status using a life-course approach

PURPOSE

Job control, the combination of skill discretion and decision authority, is considered a central component of the psychosocial working environment. This longitudinal study examines the relation between job control and risk of incident depressive disorder using a life-course approach.

METHODS

We analyze data from The Danish Work Life Course Cohort study, including all Danish individuals aged 15-30 who entered the Danish labor market during 1995-2009 and were free from depressive disorder at entry (955,573 individuals). We measured job control using a job exposure matrix. Depressive disorders were measured using information from nationwide registers of psychiatric in- and outpatient admissions. Using Cox regression models we estimated the prospective association between job control and risk of incident depressive disorders. Analyses accounted for a range of potential confounders prior to workforce entry including socioeconomic status in adolescence and parental psychiatric and somatic diagnoses prior to labor market entry, together with potential confounders in adulthood including income, education, and demographics.

RESULTS

Lower levels of past year job control were associated with a higher risk of depressive disorder after adjustment for all covariates (HR = 1.27, 95% CI 1.16-1.38). Results stratified by gender showed associations for both men (HR = 1.38, 95% CI 1.19-1.61) and women (HR = 1.19, 95% CI 1.08-1.32).

CONCLUSIONS

Our findings suggest that the level of job control at work affects the risk of clinically diagnosed depressive disorder, and that this association is not due to confounding by socioeconomic status.

Polygenic Risk: Predicting Depression Outcomes in Clinical and Epidemiological Cohorts of Youths

OBJECTIVE

Identifying risk factors for major depression and depressive symptoms in youths could have important implications for prevention efforts. This study examined the association of polygenic risk scores (PRSs) for a broad depression phenotype derived from a large-scale genome-wide association study (GWAS) in adults, and its interaction with childhood abuse, with clinically relevant depression outcomes in clinical and epidemiological youth cohorts.

METHODS

The clinical cohort comprised 279 youths with major depression (mean age=14.76 years [SD=2.00], 68% female) and 187 healthy control subjects (mean age=14.67 years [SD=2.45], 63% female). The first epidemiological cohort included 1,450 youths (mean age=13.99 years [SD=0.92], 63% female). Of those, 694 who were not clinically depressed at baseline underwent follow-ups at 6, 12, and 24 months. The replication epidemiological cohort comprised children assessed at ages 8 (N=184; 49.2% female) and 11 (N=317; 46.7% female) years. All cohorts were genome-wide genotyped and completed measures for major depression, depressive symptoms, and/or childhood abuse. Summary statistics from the largest GWAS to date on depression were used to calculate the depression PRS.

RESULTS

In the clinical cohort, the depression PRS predicted case-control status (odds ratio=1.560, 95% CI=1.230-1.980), depression severity (β=0.177, SE=0.069), and age at onset (β=-0.375, SE=0.160). In the first epidemiological cohort, the depression PRS predicted baseline depressive symptoms (β=0.557, SE=0.200) and prospectively predicted onset of moderate to severe depressive symptoms (hazard ratio=1.202, 95% CI=1.045-1.383). The associations with depressive symptoms were replicated in the second epidemiological cohort. Evidence was found for an additive, but not an interactive, effect of the depression PRS and childhood abuse on depression outcomes.

CONCLUSIONS

Depression PRSs derived from adults generalize to depression outcomes in youths and may serve as an early indicator of clinically significant levels of depression.

Mental health in spouses of U.S. Gulf War veterans

Veterans' spouses are at risk for mental distress and substance use. We examined long term psychological functioning in spouses from a national cohort of 1991 Gulf War era veterans. From clinical interviews, spouses of deployed veterans (n = 488) did not have a greater prevalence of post-war mental disorders compared to spouses of non-deployed veterans (n = 536); however, in couples that were living together since the war, there was an increased risk of anxiety disorders or any one disorder. On questionnaires, the impact varied but was most consistently observed in more severe depression and greater functional impairment in spouses of deployed compared to non-deployed veterans. If a veteran developed post-war anxious/depressive disorders or any one mental disorder, the matched spouse was more likely to develop post-war anxious/depressive disorders or any one mental disorder, respectively. Veteran combat exposure did not similarly increase the risk of spouse post-war mental disorders. Greater spouse self-reported symptomatology was observed in spouses of veterans with anxious/depressive disorders even when controlling for deployment. In summary, the war conferred greater risk for spouse mental disorders and distress for spouses of veterans with mental health disorders, with some increased risk for spouses of deployed veterans, especially in couples together since the war.

Do Sociodemographic Factors and Urban Green Space Affect Mental Health Outcomes Among the Urban Elderly Population?

The mounting mental health issues faced by elderly urban residents increase the social and economic costs to society associated with dementia and depression. Therefore, it is necessary to identify the characteristics of elderly urban residents suffering from mental health issues, to address these issues more effectively. We used 2015 Community Health Survey data from the Korea Centers for Disease Control and Prevention to identify the demographic and social characteristics of 11,408 elderly urban residents in relation to stress levels and symptoms of depression in seven metropolitan areas in Korea, and to calculate the odds ratio for urban green space. We found that the prevalence of these mental health issues generally decreased in relation to the ratio of green space of an area. These findings suggest identifying elderly people who are vulnerable to certain mental health issues based on demographic and social characteristics and demonstrate that the ratio of urban green space within a community is an important component in improving mental health outcomes for elderly urban residents. These findings have policy implications for assisting elderly people vulnerable to certain mental health issues and for establishing a green welfare policy targeting this population.

Genetic Markers in Psychiatry

Psychiatric disorders such as addiction (substance use and addictive disorders), depression, eating disorders, schizophrenia, and post-traumatic stress disorder (PTSD) are severe, complex, multifactorial mental disorders that carry a high social impact, enormous public health costs, and various comorbidities as well as premature morbidity. Their neurobiological foundation is still not clear. Therefore, it is difficult to uncover new set of genes and possible genetic markers of these disorders since the understanding of the molecular imbalance leading to these disorders is not complete. The integrative approach is needed which will combine genomics and epigenomics; evaluate epigenetic influence on genes and their influence on neuropeptides, neurotransmitters, and hormones; examine gene × gene and gene × environment interplay; and identify abnormalities contributing to development of these disorders. Therefore, novel genetic approaches based on systems biology focused on improvement of the identification of the biological underpinnings might offer genetic markers of addiction, depression, eating disorders, schizophrenia, and PTSD. These markers might be used for early prediction, detection of the risk to develop these disorders, novel subtypes of the diseases and tailored, personalized approach to therapy.

Why Is Maternal Depression Related to Adolescent Internalizing Problems? A 15-Year Population-Based Study

OBJECTIVE

Exposure to maternal depression during early childhood is a well-documented risk factor for offspring's internalizing problems, but the long-term risk and the psychosocial mechanisms underlying the association remain largely unknown. We examined whether maternal depression during early childhood was associated with offspring internalizing problems in adolescence, and the extent to which negative parenting, peer victimization, and poor friendship quality during middle childhood mediated this association.

METHOD

We report on a population-based sample of children (n = 1,443) followed-up from 5 months to 15 years. We use yearly assessments of the exposure variable, that is, maternal depression (5 months to 5 years); the putative mediators, that is, peer victimization, friendship quality, and parenting practices (6-12 years); and assessment of the outcome variables at 15 years: self-reported major depressive (MD), generalized anxiety (GA), and social phobia (SP) symptoms. Structural equation modeling was used to test mediation by peer and family relationships.

RESULTS

Exposure to maternal depression during early childhood was associated with higher levels of adolescent MD, GA, and SP. Peer victimization was the only significant mediator and explained 35.9% of the association with adolescent MD, 22.1% of that with GA, and 22.1% of that with SP.

CONCLUSION

Exposure to maternal depression prior to age 5 years was associated with depression, anxiety, and social phobia extending to adolescence via its impact on peer victimization during middle childhood. Particular attention should be paid to victimization as one potential psychosocial factor via which maternal depression is associated with adolescent internalizing problems.

Curtailing the communicability of psychiatric disorders

Although psychiatric disorders are classified as non-communicable diseases, we believe this classification is too rigid and limiting. We present evidence of the communicability of psychiatric disorders through three major pathways: infectious and ecological, familial, and sociocultural communicability. Successful strategies developed to control the spread of communicable infectious diseases are relevant to curtailing the communicability of psychiatric disorders, thereby reducing their burden. Current interventions and policies that conceptualise psychiatric illnesses as non-communicable mostly focus on the individual. By applying strategies from infectious disease and chronic illness prevention models within a socioecological framework, we posit a broad communicable chronic disease psychiatric illness control plan for effectively treating the patient with the psychiatric disorder (host) as early as possible, providing benefits to their family and the community, and preventing transmission to others.

Polygenic risk for severe psychopathology among Europeans is associated with major depressive disorder in Han Chinese women

BACKGROUND

Previous studies have demonstrated that several major psychiatric disorders are influenced by shared genetic factors. This shared liability may influence clinical features of a given disorder (e.g. severity, age at onset). However, findings have largely been limited to European samples; little is known about the consistency of shared genetic liability across ethnicities.

METHOD

The relationship between polygenic risk for several major psychiatric diagnoses and major depressive disorder (MDD) was examined in a sample of unrelated Han Chinese women. Polygenic risk scores (PRSs) were generated using European discovery samples and tested in the China, Oxford, and VCU Experimental Research on Genetic Epidemiology [CONVERGE (maximum N = 10 502)], a sample ascertained for recurrent MDD. Genetic correlations between discovery phenotypes and MDD were also assessed. In addition, within-case characteristics were examined.

RESULTS

European-based polygenic risk for several major psychiatric disorder phenotypes was significantly associated with the MDD case status in CONVERGE. Risk for clinically significant indicators (neuroticism and subjective well-being) was also associated with case-control status. The variance accounted for by PRS for both psychopathology and for well-being was similar to estimates reported for within-ethnicity comparisons in European samples. However, European-based PRS were largely unassociated with CONVERGE family history, clinical characteristics, or comorbidity.

CONCLUSIONS

The shared genetic liability across severe forms of psychopathology is largely consistent across European and Han Chinese ethnicities, with little attenuation of genetic signal relative to within-ethnicity analyses. The overall absence of associations between PRS for other disorders and within-MDD variation suggests that clinical characteristics of MDD may arise due to contributions from ethnicity-specific factors and/or pathoplasticity.

Motivated attention and family risk for depression: Neuronal generator patterns at scalp elicited by lateralized aversive pictures reveal blunted emotional responsivity

Behavioral and electrophysiologic evidence suggests that major depression (MDD) involves right parietotemporal dysfunction, a region activated by arousing affective stimuli. Building on prior event-related potential (ERP) findings (Kayser et al. 2016 NeuroImage 142:337–350), this study examined whether these abnormalities also characterize individuals at clinical high risk for MDD. We systematically explored the impact of family risk status and personal history of depression and anxiety on three distinct stages of emotional processing comprising the late positive potential (LPP). ERPs (72 channels) were recorded from 74 high and 53 low risk individuals (age 13–59 years, 58 male) during a visual half-field paradigm using highly-controlled pictures of cosmetic surgery patients showing disordered (negative) or healed (neutral) facial areas before or after treatment. Reference-free current source density (CSD) transformations of ERP waveforms were quantified by temporal principal components analysis (tPCA). Component scores of prominent CSD-tPCA factors sensitive to emotional content were analyzed via permutation tests and repeated measures ANOVA for mixed factorial designs with unstructured covariance matrix, including gender, age and clinical covariates. Factor-based distributed inverse solutions provided descriptive estimates of emotional brain activations at group level corresponding to hierarchical activations along ventral visual processing stream. Risk status affected emotional responsivity (increased positivity to negative-than-neutral stimuli) overlapping early N2 sink (peak latency 212 ms), P3 source (385 ms), and a late centroparietal source (630 ms). High risk individuals had reduced right-greater-than-left emotional lateralization involving occipitotemporal cortex (N2 sink) and bilaterally reduced emotional effects involving posterior cingulate (P3 source) and inferior temporal cortex (630 ms) when compared to those at low risk. While the early emotional effects were enhanced for left hemifield (right hemisphere) presentations, hemifield modulations did not differ between risk groups, suggesting top-down rather than bottom-up effects of risk. Groups did not differ in their stimulus valence or arousal ratings. Similar effects were seen for individuals with a lifetime history of depression or anxiety disorder in comparison to those without. However, there was no evidence that risk status and history of MDD or anxiety disorder interacted in their impact on emotional responsivity, suggesting largely independent attenuation of attentional resource allocation to enhance perceptual processing of motivationally salient stimuli. These findings further suggest that a deficit in motivated attention preceding conscious awareness may be a marker of risk for depression.

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Emotional hemifield ERP task with 127 individuals at high and low family risk for MDD

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CSD-PCA methods summarized affective modulation of late positive potential (LPP).

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High risk and prior diagnosis of MDD or anxiety disorder independently reduced LPP.

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Suggested hypoarousal (top-down) of right temporoparietal and other emotional regions

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Left hemifield (bottom-up) modulations of early emotional asymmetries were preserved.

Anxiety genetics: Dispatches from the frontier

Anxiety disorders are the most common class of psychiatric disorders and incur an enormous burden in terms of economic costs, disability and personal suffering. Despite their public health importance and documented heritability, genetic research aimed at identifying the genetic contributions to these disorders has had limited success, particularly in comparison to recent advances in the genetics of other major psychiatric disorders. The major factor contributing to this lagging progress has been a dearth of well-powered genomic studies. As a result, the genetic basis of anxiety disorders remains a largely uncharted frontier. In this Special Issue, we bring together dispatches from this frontier, reflecting a range of strategies being pursued including genomewide common variant association studies, exome sequencing, genetic prediction of treatment response, cross-disorder genetic epidemiology, and the prospects for dissecting underlying anxiety domains using the RDoC framework. Overall, these efforts underscore the genetic and phenotypic complexity of pathologic anxiety and the urgent need for more powerful and comprehensive analyses if we are to make real progress in advancing this important frontier. © 2017 Wiley Periodicals, Inc.

Hostile parenting, parental psychopathology, and depressive symptoms in the offspring: a 32-year follow-up in the Young Finns study

BACKGROUND

Both hostile parenting and parental psychopathology have been shown to predict depression in the offspring. However, whether and how they interact in predicting the longitudinal course of depression from adolescence to adulthood remains unclear.

METHODS

Participants were from the prospective Cardiovascular Risk in Young Finns study, aged 3-18 years at baseline in 1980. We used multilevel modeling for repeated measurements to examine the associations of hostile parenting (i.e., parental intolerance and emotional distance) and parental history of psychopathology with trajectories of depressive symptoms across five study phases from 1992 to 2012.

RESULTS

On average, depressive symptoms decreased in a curvilinear pattern with age. A relatively steep decreasing trend was also observed among offspring of parents with a history of psychopathology but low intolerance. By contrast, among the offspring of parents with a history of psychopathology and high intolerance there was a rising trend in depressive symptoms starting from young adulthood. There was no similar interaction between parental history of psychopathology, emotional distance, and age.

LIMITATIONS

Non-standardized, parental self-report scales were used to measure hostile parenting. The observed effects were small, and the depressive symptoms scale applied in the study may not be used for measuring clinical depression.

CONCLUSIONS

Parental psychopathology might render individuals sensitive to the unfavorable characteristics of the caregiving environment. Intolerance towards the child can exacerbate the effects of parental psychopathology and have a long-term significance on the developmental trajectory of depressive symptoms over the life-course.