Depression, Stressful Life Events, and the Impact of Variation in the Serotonin Transporter: Findings from the National Longitudinal Study of Adolescent to Adult Health (Add Health)

Mental health and BMI in children and adolescents during one year in obesity treatment

BACKGROUND

Mental health plays a major role in children and adolescents with obesity. The aim of this study was (1) to compare mental health in children with obesity with the background population and (2) to investigate if mental health changed during one year in an obesity treatment program.

METHODS

Data on self-reported mental health was collected in 107 children and adolescents (mean age 13.2 years) with obesity at first visit in an obesity treatment program and at one year follow-up (n = 47). Mental health was assessed by eight questions from the Danish Health Behaviour in School-aged Children (HBSC) questionnaire: (1) self-rated health (2) life satisfaction (3) feeling low (4) body-image (5) loneliness (6) self-esteem (7) self-efficacy and (8) social competence. Data was compared to a reference population based on HBSC data. BMI-SDS was based on Danish reference values.

RESULTS

Children and adolescents with obesity had significantly higher odds of reporting negative body image and feeling low and lower odds of reporting high self-rated health and high self-esteem compared to a reference population. There was no difference between the groups regarding life-satisfaction, social competence, self-efficacy or feeling lonely. There were no significant changes in mental health from first visit to one-year follow-up.

CONCLUSION

Our findings highlight the mental health difficulties in children and adolescents with obesity, and the importance of addressing these issues in obesity treatment. The results also indicate that children with obesity have psychosocial resources that should be exploited in treatment protocols.

Emotional control in selected somatic and psychiatric diseases

THE AIM

was to assess the level of subjective control of emotional states among patients treated for dermatological and gastrointestinal somatic diseases compared to those with depressive and anxiety disorders. The results were related to the analyzed dimensions of emotion regulation in healthy subjects.

MATERIALS AND METHODS

The reports of the conducted studies were compiled for a total of 310 people, including 120 patients diagnosed with a somatic disease (psoriasis, rosacea, irritable bowel syndrome, and gastroesophageal reflux), as well as 96 patients diagnosed with depressive disorders and 30 patients with anxiety disorders. The control group consisted of healthy subjects (64 individuals). To assess the psychological variables analyzed, the subjects completed the Emotion Regulation Questionnaire developed by J. Brzeziński.

RESULTS

The study showed that the patients suffering from a chronic somatic symptom disorder, similarly to those treated for depression and anxiety disorders, differed from the healthy individuals in most aspects of emotional control. The patients with dermatological and gastrointestinal diseases differed statistically significantly from the patients with depression and the patients with anxiety disorders in relation to three dimensions of emotional control. Patients with a somatic disease are characterized by higher emotional and rational motivation, lower emotional resilience and lower emotional arousal.

CONCLUSIONS

A chronic disease co-occurs with the emotional sphere of a person's daily functioning. Regardless of the diagnosis in terms of somatic disorders and mental illnesses, the way in which emotional states are controlled can be an important factor in the onset of the disease, coping with it as well as the treatment process.

A prospective study of the relative contribution of adolescent peer support quantity and quality to depressive symptoms

BACKGROUND

During adolescence, peer support has an increasingly important role in identity formation and well-being. Prior research has identified that lack of social support from peers in adolescence is a potent risk factor for depression. Two ways that social support has been operationalized is by the number of one's friends (i.e., 'quantity') and perception of one's network (i.e., 'quality'). Typically, these aspects of peer support are assessed separately.

METHODS

Using data from the National Longitudinal Study of Adolescent to Adult Health (N = 3,857), this study sought to test whether (1) adolescent depression relates to having fewer friends versus lower quality friendships, (2) these aspects of adolescent peer support prospectively predict depression in adulthood, (3) gender moderates the effects of peer support on depression, and (4) these aspects of peer support buffer the effects of stressful life events on depression.

RESULTS

Peer support quality uniquely predicted depression in adolescence and adulthood among both males and females. The effect of peer support quality on depressive symptoms, however, was greater for females than males. By contrast, peer support quantity did not uniquely predict depression for males or females.

CONCLUSIONS

Qualitative aspects of adolescent peer support uniquely contribute to mental health not only in adolescence, but in adulthood as well. Potential processes through which peer support relates to depression are discussed, as well as implications for treatment.

Twenty-Five Years of National-Level Research on Adolescent and Young Adult Mental Health in the United States

The longitudinal, population-level, biosocial data in the National Longitudinal Study of Adolescent to Adult Health (Add Health) have elucidated the developmental course of mental health across early stages of the life course. This data set also has been invaluable for documenting and unpacking disparities in these developmental patterns by race, ethnicity, socioeconomic status, gender, immigration, and sexuality. Reflecting the larger focus of this special supplement on Add Health as a tool for connecting adolescence to adulthood, this article reviews Add Health research since 2000 based on a search of key mental health terms, primarily describing patterns of two key markers of psychopathology (depressive symptoms, suicidal ideation) that were consistently measured across waves. It situates these patterns from adolescence into adulthood within the developmental ecology organized by the proximate settings of everyday life, the larger social structures organized by a highly stratified society, and the relations of these ecological and structural forces to biological processes. Major foci are the dynamic nature of mental health across the life course and the ways that ecological and physiological influences on mental health differ by group identity and social position.

Ways of Coping with Stress among Patients with Depressive Disorders

Background: Experiencing stressful life events and ways of coping with them can predispose to the onset of depressive mood disorders, while depression itself can be responsible for severe stress and can weaken resilience to stressors. Thus, variables relevant to the onset of depressive episodes and the course of depression have significant relationships with coping strategies to stressors. The aim of this research was to evaluate the most commonly used stress-coping strategies in patients treated for depression compared to patients with anxiety disorders and to healthy subjects. Methods: The multidimensional coping inventory (COPE Inventory) by C. S. Carver, M. F. Scheier, and J. K. Weintraub, covering 15 stress response strategies included in more general and overarching coping styles, was used in the study. Results: Patients with depression differed from the healthy subjects in a statistically significant way. Statistical analysis showed that people with depression are less likely than healthy subjects to use Active Coping, Planning, Seeking of Instrumental and Emotional Social Support, Suppression of Competing Activities, and Positive Reinterpretation. In contrast, they are more likely to use Denial, Mental Disengagement, and Behavioral Disengagement compared to those not treated for mental disorders. The patients with depressive disorders, compared to the group of patients with anxiety disorders, scored significantly differently on stress coping strategies in only two types of actions taken in stressful situations. Conclusion: The patients with depression differed from the healthy subjects in terms of the highest number of the stress coping strategies assessed. Compared to the healthy individuals, a tendency toward an avoidant behavior style was prevalent among the depressed patients. There was no statistically significant difference between the patients with the first episode of the disease and recurrent depressive disorders in terms of stress coping strategies.

Time moderates the interplay between 5-HTTLPR and stress on depression risk: gene x environment interaction as a dynamic process

The serotonin-transporter-linked promoter region (5-HTTLPR) has been widely investigated as contributing to depression vulnerability. Nevertheless, empirical research provides wide contrasting findings regarding its involvement in the etiopathogenesis of the disorder. Our hypothesis was that such discrepancy can be explained considering time as moderating factor. We explored this hypothesis, exploiting a meta analytic approach. We searched PubMed, PsychoINFO, Scopus and EMBASE databases and 1096 studies were identified and screened, resulting in 22 studies to be included in the meta-analyses. The effect of the 5-HTTLPR x stress interaction on depression risk was found to be moderated by the following temporal factors: the duration of stress (i.e. chronic vs. acute) and the time interval between end of stress and assessment of depression (i.e. within 1 year vs. more than 1 year). When stratifying for the duration of stress, the effect of the 5-HTTLPR x stress interaction emerged only in the case of chronic stress, with a significant subgroup difference (p = 0.004). The stratification according to time interval revealed a significant interaction only for intervals within 1 year, though no difference between subgroups was found. The critical role of time interval clearly emerged when considering only chronic stress: a significant effect of the 5-HTTLPR and stress interaction was confirmed exclusively within 1 year and a significant subgroup difference was found (p = 0.01). These results show that the 5-HTTLPR x stress interaction is a dynamic process, producing different effects at different time points, and indirectly confirm that s-allele carriers are both at higher risk and more capable to recover from depression. Overall, these findings expand the current view of the interplay between 5-HTTLPR and stress adding the temporal dimension, that results in a three-way interaction: gene x environment x time.

Going beyond risk factor: Childhood maltreatment and associated modifiable targets to improve life-long outcomes in mood disorders

Childhood maltreatment increases risk for mood disorders and is associated with earlier onset-and more pernicious disease course following onset-of mood disorders. While the majority of studies to date have been cross-sectional, longitudinal studies are emerging and support the devastating role(s) childhood maltreatment has on development of, and illness course in, mood disorders. This manuscript extends prior reviews to emphasize more recent work, highlighting longitudinal data, and discusses treatment studies that provide clues to mechanisms that mediate disease risk, course, relapse, and treatment response. Evidence suggesting systemic inflammation, alterations in hypothalamic-pituitary-adrenal (HPA) axis function and corticotropin-releasing factor (CRF) neural systems, genetic and other familial factors as mechanisms that mediate risk and onset of, and illness course in, mood disorders following childhood maltreatment is discussed. Risky behaviors following maltreatment, e.g., substance use and unhealthy lifestyles, may further exacerbate alterations in the HPA axis, CRF neural systems, and systematic inflammation to contribute to a more pernicious disease course. More research on sex differences and the impact of maltreatment in vulnerable populations is needed. Future research needs to be aimed at leveraging knowledge on modifiable targets, going beyond childhood maltreatment as a risk factor, to inform prevention and treatment strategies and foster trauma-informed care.

Effects of somatic treatments on suicidal ideation and completed suicides

OBJECTIVE

This work was undertaken to define and characterize the role of currently available somatic treatments in psychiatry in either increasing or reducing the risk for suicide.

METHODS

Members of the Suicide Prevention Task Group of the National Network of Depression Centers performed a literature review of somatic treatments known to increase or reduce the risk for suicide. The reviews ventured to include all relevant information about the risk for both suicide ideation and completed suicides.

RESULTS

Lithium and clozapine are the only two somatic treatments that have high-quality data documenting their antisuicide effects in mood disorders and schizophrenia, respectively. Lithium discontinuation is also associated with increased suicide risk. Ketamine and esketamine may have a small, but immediate, antisuicide effect. Despite the recent Food and Drug Administration approval of esketamine use in depressed suicidal patients, the small disproportional overrepresentation of suicide in subjects who had received esketamine versus placebo (3 vs. 0 among > 3500 subjects) requires ongoing evaluation. The purported antisuicide effect of electroconvulsive therapy is based on low-quality data. The effect of antidepressants is not at all clear. There appears to be direct evidence for antidepressants increasing suicidal ideation and the risk for suicide over the short-term in young people, but indirect (low quality) evidence that antidepressants reduce suicide risk over the long term.

CONCLUSIONS

Clinicians have an expanding pharmacopeia to address suicide potential in their patients. Some of the agents with documented antisuicide effects may also increase suicidality under specific circumstances.

Does Culture Influence Antidepressant Response? A Preliminary Investigation of Randomized Controlled Trials of Fluoxetine

Background

Contemporary models of depression view the disorder as arising from an interaction between genetic vulnerability and adverse life experiences. The nature of these experiences is strongly influenced by social-cultural factors, and there is preliminary evidence that these factors may influence the response to treatment.

Methods

In this pilot study, pooled response rates obtained from 56 randomized controlled trials of fluoxetine for major depression, conducted across 21 countries, were analyzed in relation to Hofstede’s six dimensions of culture in these countries, while controlling for methodological quality.

Results

The cultural dimensions of power distance (r = .62, p = .002), masculinity (r = .45, p = .04) and indulgence (r = -.52, p = .016) were significantly correlated with antidepressant response rates, though only the first of these remained significant after correction for multiple comparisons. On linear regression analysis, the association between power distance and antidepressant response remained significant (β = .62, p = .002).

Conclusions

These preliminary results suggest that certain cultural factors may be significantly associated with cross-national variations in antidepressant response rates during clinical trials.

The 5-HTTLPR-rs25531 S-A-S-A Haplotype and Chronic Stress Moderate the Association Between Acute Stress and Internalizing Mental Disorders Among HIV+ Children and Adolescents in Uganda

Background: Internalizing mental disorders (IMDs) among HIV-positive (HIV+) children and adolescents are associated with poor disease outcomes, such as faster HIV disease progression. Although it has been suggested that the development of IMDs is moderated by interaction of stressful life events and vulnerability factors, the underlying etiology is largely unknown. Serotonin transporter gene [solute carrier family 6 member A4 (SLC6A4)] and human tryptophan hydroxylase 2 gene (TPH2) polymorphisms have been implicated in the development of IMDs. This study investigated the association between acute stress and IMDs, and moderation by chronic stress and genetic variants in SLC6A4 and TPH2. Hypothesis: Acute stress acts through genetic and environmental vulnerability factors to increase the risk of developing IMDs. Methods: Polymorphisms in SLC6A4 (5-HTTLPR, rs25531, 5-HTTLPR-rs25531, and STin2 VNTR) and TPH2 (rs1843809, rs1386494, rs4570625, and rs34517220) were genotyped in 368 HIV+ children and adolescents (aged 5-17 years) with any internalizing mental disorder (depression, anxiety disorders, or posttraumatic stress disorder), and 368 age- and sex-matched controls, who were also HIV+. Chronic and acute stress categories were derived by hierarchical cluster analysis. Logistic regression analysis was used to assess the independent moderating effect of chronic stress and each selected polymorphism on the association between acute stress and IMDs. Results: We observed a statistically significant association between severe acute stress and IMDs (p = 0.001). Children and adolescents who experienced severe acute stress were twice as likely to develop IMDs, compared to children and adolescents who experienced mild acute stress (p = 0.001). Chronic stress interacted with severe acute stress to increase the risk of IMDs (p = 0.033). Acute stress was found to interact with 5-HTTLPR-rs25531 S-A-S-A haplotype to increase the risk for IMDs among Ugandan HIV+ children and adolescents (p = 0.049). We found no evidence for a combined interaction of acute stress, chronic stress, and 5-HTTLPR-rs25531 on IMDs. Conclusion: The odds of having an internalizing mental disorder (IMD) were higher among HIV+ children and adolescents who experienced severe acute stress compared to HIV+ children and adolescents who experienced mild acute stress. Chronic stress and 5-HTTLPR-rs25531 independently moderated the association between acute stress and IMDs.

Suicidal ideation and aggression in childhood, genetic variation and young adult depression

BACKGROUND

Suicidal thoughts and behaviors have been studied in association with a variety of risk factors. The aim of the present study was to determine if levels of child/adolescent aggression and/or variation in candidate genes previously associated with suicidal behaviors in adults would influence the presence of suicidal ideation in childhood/adolescence, and to determine if ideation was associated with young adult depression.

METHODS

A longitudinal study of children, adolescents and young adults who were at high or low risk for alcohol and other substance use disorders by familial background were assessed. The Child Behavior Checklist (CBCL) aggression scale scores with derived subtypes (physical and relational) and genetic variation (ANKK1, DRD2, COMT, SLC6A4, HTR2C) were used as predictors of the presence and onset of suicidal ideation in childhood using survival analysis. Structural equation models (SEM) were fit to determine the relative importance of the predictors controlling for background variables.

RESULTS

CBCL aggression was significantly associated with child/adolescent suicidal ideation. One SNP in the ANKK1 gene (rs1800497), one in the HTR2C gene (rs6318), and two haplotypes, AAAC in the ANKK1-DRD2 complex and the CCC haplotype of the HTR2C gene, were significantly associated with the presence and onset of child/adolescent suicidal ideation. Follow up in young adulthood showed a significant relationship between suicidal ideation in childhood/adolescence and young adult depression.

CONCLUSIONS

Genetic variation and presence of elevated aggression scores from the childhood CBCL are significant predictors of childhood suicidal ideation. Suicidal ideation in childhood and being female are predictors of young adult depression.

Gender Differences in Depression: Evidence From Genetics

Compared with men, female accounts for a larger proportion of patients with depression. Behavioral genetics researches find gender differences in genetic underpinnings of depression. We found that gender differences exist in heritability and the gene associated with depression after reviewing relevant research. Both genes and gene-environment interactions contribute to the risk of depression in a gender-specific manner. We detailed the relationships between serotonin transporter gene-linked promoter region (5-HTTLPR) and depression. However, the results of these studies are very different. We explored the reasons for the contradictory conclusions and provided some suggestions for future research on the gender differences in genetic underpinnings of depression.

Evaluation of the role of stress in patients with breast cancer and depression by paykel's life event and adaptive neuro-fuzzy approach

INTRODUCTION

The aim of this study was to identify and analyze the stress factors and the level of stress a year preceding the onset of breast cancer and depression in the studied female patients.

METHODS

The research in this work was mostly prospectively (clinical and analytical). During the research, Scale of Life Events-Paykel was applied. Stressful life events differed significantly between the groups. In the studied group, the following events were significantly more prevalent: partner infidelity (χ²  = 12.663; p < .001), failure at work (χ²  = 44.429; p < .001), and spontaneous abortions or stillbirths (χ²  = 13.818; p < .001).

RESULTS

According to the results of this study, stressful life events differed significantly between the observed groups. These stressful life events had a significant impact on the increase of risk for breast cancer, as well as on depressivity. Afterward, adaptive neuro-fuzzy inference system was used for prediction of the Paykel's Life Event according to Fisher's exact test.

CONCLUSION

The obtained results could be of practical usage for improving stress behavior of the patients with breast cancer and depression.

"Out, out, brief candle! Life's but a walking shadow": 5-HTTLPR Is Associated With Current Suicidal Ideation but Not With Previous Suicide Attempts and Interacts With Recent Relationship Problems

BACKGROUND

Suicide is an unresolved psychiatric and public health emergency, claiming 800,000 lives each year, however, its neurobiological etiology is still not understood. In spite of original reports concerning the involvement of 5-HTTLPR in interaction with recent stress in the appearance of suicidal ideation and attempts, replication studies have yielded contradictory results. In our study, we analyzed the association between 5-HTTLPR and lifetime suicide attempts, current suicidal ideation, hopelessness and thoughts of death as main effects, and in interaction with childhood adversities, recent stress, and different types of recent life events in a general population sample.

METHODS

Two thousand and three hundred fifty-eight unrelated European volunteers were genotyped for 5-HTTLPR, provided phenotypic data on previous suicide attempts, and current suicidal ideation, hopelessness and thoughts about death, and information on childhood adversities and recent life events. Logistic and linear regression models were run with age, gender, and population as covariates to test for the effect of 5-HTTLPR as a main effect and in interaction with childhood adversities and recent life events on previous suicide attempts and current suicidal ideation. Benjamini-Hochberg FDR Q values were calculated to correct for multiple testing.

RESULTS

5-HTTLPR had no significant effect on lifetime suicide attempts either as a main effect on in interaction with childhood adversities. 5-HTTLPR had a significant main effect on current suicidal ideation in the dominant model (Q=0.0344). 5-HTTLPR did not interact with childhood adversities or total number of recent life events on any phenotypes related to current suicidal risk, however, a significant interaction effect between 5-HTTLPR and current relationship problems emerged in the case of current suicidal ideation in the dominant model (Q=0.0218) and in the case of thoughts about death and dying in the dominant (Q=0.0094) and additive models (Q=0.0281).

CONCLUSION

While 5-HTTLPR did not influence previous suicide attempts or interacted with childhood adversities, it did influence current suicidal ideation with, in addition, an interaction with recent relationship problems supporting the involvement of 5-HTTLPR in suicide. Our findings that 5-HTTLPR impacts only certain types of suicide risk-related behaviors and that it interacts with only distinct types of recent stressors provides a possible explanation for previous conflicting findings.

Quality of life, depressive and minor psychiatrics symptoms in nursing students

ABSTRACT Objective: To assess quality of life, prevalence of depressive and minor psychiatric symptoms in Nursing students. Methods: Cross-sectional study, conducted from March to April 2018, at a federal university. Sample composed of 242 Nursing students, from the 1st to the 8th semester. Data was collected using the quality of life instruments, Beck Depression Inventory and Self-Report Questionnaire. A significance level of 0.05 was considered. Results: The mean age was 22.9 ± 5.1 years. It was found that 25% of the students had severe depressive symptoms and 54% of the students had minor psychiatric disorders, with a higher prevalence in the first semesters. An inverse relationship was observed between the frequency of depressive symptoms and quality of life scores (p = 0.05). Conclusion: Nursing students showed a high prevalence of depressive symptoms, indicating the importance of implementing actions to promote and prevent mental health.

The Devastating Clinical Consequences of Child Abuse and Neglect: Increased Disease Vulnerability and Poor Treatment Response in Mood Disorders

A large body of evidence has demonstrated that exposure to childhood maltreatment at any stage of development can have long-lasting consequences. It is associated with a marked increase in risk for psychiatric and medical disorders. This review summarizes the literature investigating the effects of childhood maltreatment on disease vulnerability for mood disorders, specifically summarizing cross-sectional and more recent longitudinal studies demonstrating that childhood maltreatment is more prevalent and is associated with increased risk for first mood episode, episode recurrence, greater comorbidities, and increased risk for suicidal ideation and attempts in individuals with mood disorders. It summarizes the persistent alterations associated with childhood maltreatment, including alterations in the hypothalamic-pituitary-adrenal axis and inflammatory cytokines, which may contribute to disease vulnerability and a more pernicious disease course. The authors discuss several candidate genes and environmental factors (for example, substance use) that may alter disease vulnerability and illness course and neurobiological associations that may mediate these relationships following childhood maltreatment. Studies provide insight into modifiable mechanisms and provide direction to improve both treatment and prevention strategies.

Dynamic interaction of genetic risk factors and cocaine abuse in the background of Parkinsonism - a case report

Background

Parkinsonism is a complex multifactorial neurodegenerative disorder, in which genetic and environmental risk factors may both play a role. Among environmental risk factors cocaine was earlier ambiguously linked to Parkinsonism. Former single case reports described Parkinsonism in chronic cocaine users, but an epidemiological study did not confirm an increased risk of Parkinson’s disease. Here we report a patient, who developed Parkinsonism in young age after chronic cocaine use, in whom a homozygous LRRK2 risk variant was also detected.

Case presentation

The patient was investigated because of hand tremor, which started after a 1.5-year period of cocaine abuse. Neurological examination suggested Parkinsonism, and asymmetrical pathology was confirmed by the dopamine transporter imaging study. The genetic investigations revealed a homozygous risk allele in the LRRK2 gene. After a period of cocaine abstinence, the patient’s symptoms spontaneously regressed, and the dopamine transporter imaging also returned to near-normal.

Conclusions

This case report suggests that cocaine abuse indeed might be linked to secondary Parkinsonism and serves as an example of a potential gene-environmental interaction between the detected LRRK2 risk variant and cocaine abuse. The reversible nature of the DaTscan pathology is a unique feature of this case, and needs further evaluation, whether this is incidental or can be a feature of cocaine related Parkinsonism.

Influence of early adversity on cortisol reactivity, SLC6A4 methylation and externalizing behavior in children of alcoholics

BACKGROUND

Children of parents with alcoholism face considerable stress, and often have externalizing behaviors. Early adversity is known to affect DNA methylation and the functioning of the HPA axis. We investigated the association of early adversity with cortisol reactivity, 5HTTLPR genotype, site specific DNA methylation in the SLC6A4 gene and externalizing behavior in children of alcoholics (COA), and a matched sample of control children.

METHODS

We examined children of alcoholics (N = 50) and age matched control children (N = 50) for exposure to early adversity (both prenatal and postnatal), assessed their salivary cortisol reactivity and evaluated their levels of emotional and behavioral difficulty in terms of externalizing and internalizing behavior. Site-specific DNA methylation at a previously characterized SLC6A4 region was determined in salivary DNA using pyrosequencing. The 5HTTLPR region of the SLC6A4 gene was also genotyped.

RESULTS

COA had significantly higher experience of early adversity than control children. Cortisol reactivity was reduced in COA, and negatively correlated with early adversity. Both early adversity and cortisol reactivity correlated with externalizing behavior. SLC6A4 methylation was higher in COA, and correlated with early adversity. SLC6A4 genotype did not show association with any of the variables.

CONCLUSION

Our study provides further evidence that early adversity is associated with blunted cortisol reactivity, increased site-specific CpG DNA methylation at the SLC6A4 gene, and high externalizing behavior.

The serotonin transporter gene variants modulate acute stress-induced hippocampus and dorsomedial prefrontal cortex activity during memory retrieval

The short (s) allele of a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) is related to reduced serotonin transporter efficiency and an increased vulnerability to stress and mental disorders. In the present study, we investigated how 5-HTTLPR impacts on memory retrieval under stress and related neural activity by reanalyzing a small genetic neuroimaging data set. Twenty-seven healthy male volunteers participated in both the Trier Social Stress Test (TSST) and a respective control procedure and then their brain activity was measured with functional MRI (fMRI) while they performed an emotional-face-recognition task. Sixteen participants were carriers of the short allele (ss/sl carriers) and 11 were homozygous for the long allele (ll carriers). Genotype groups were compared with respect to stress-related physiological changes, memory performance, and brain activity. No significant genotype-dependent effects on memory performance or cortisol levels were found. The ss/sl carriers showed significantly higher systolic and diastolic blood pressure than the ll carriers, independent of stress. The ss/sl carriers reported stronger stress-induced nervous mood than the ll carriers. Our fMRI data revealed that the ss/sl carriers showed significantly weaker left hippocampus activation and stronger dorsomedial prefrontal cortex (dmPFC) deactivation when retrieving memories under stress as compared with the ll carriers. Subsequent analyses revealed that the distinct hippocampal activation pattern in both genotypes was associated with stress-induced cortisol elevation, while the distinct dmPFC activation pattern in both genotypes was associated with stress-induced changes in reaction times. Our results thus add new evidence that serotonin signaling modulates neural activity in the hippocampus and dmPFC during memory retrieval under acute psychosocial stress.

Interpreting Behavior Genetic Models: Seven Developmental Processes to Understand

Behavior genetic findings figure in debates ranging from urgent public policy matters to perennial questions about the nature of human agency. Despite a common set of methodological tools, behavior genetic studies approach scientific questions with potentially divergent goals. Some studies may be interested in identifying a complete model of how individual differences come to be (e.g., identifying causal pathways among genotypes, environments, and phenotypes across development). Other studies place primary importance on developing models with predictive utility, in which case understanding of underlying causal processes is not necessarily required. Although certainly not mutually exclusive, these two goals often represent tradeoffs in terms of costs and benefits associated with various methodological approaches. In particular, given that most empirical behavior genetic research assumes that variance can be neatly decomposed into independent genetic and environmental components, violations of model assumptions have different consequences for interpretation, depending on the particular goals. Developmental behavior genetic theories postulate complex transactions between genetic variation and environmental experiences over time, meaning assumptions are routinely violated. Here, we consider two primary questions: (1) How might the simultaneous operation of several mechanisms of gene-environment (GE)-interplay affect behavioral genetic model estimates? (2) At what level of GE-interplay does the 'gloomy prospect' of unsystematic and non-replicable genetic associations with a phenotype become an unavoidable certainty?

Associations Between Adolescent Chronic Pain and Prescription Opioid Misuse in Adulthood

Prescription opioid misuse is a serious public health concern, yet antecedent factors are poorly described. Using data from the National Longitudinal Study of Adolescent to Adult Health (N = 14,784), we examined the longitudinal relationship between a history of adolescent chronic pain and the odds of misusing prescription opioids in adulthood. The primary predictor variable was chronic pain status during adolescence. The primary outcome variables were prescription opioid misuse during early adulthood and adulthood. Multivariate models controlled for known risk factors of opioid misuse, including sociodemographics (sex, race, and ethnicity), adolescent mental health symptoms (anxiety, depression), adolescent self-reported physical health status, adolescent substance use/abuse, childhood trauma, and adult legitimate opioid use. We found that adults with a history of adolescent chronic pain were more likely to misuse opioids than those without history of chronic pain, even after controlling for other known risk factors. Further, we found that among individuals with history of adolescent chronic pain that race (white), other substance use, and exposure to trauma were risk factors for later opioid misuse. Longitudinal associations between adolescent chronic pain and subsequent adult prescription opioid misuse highlight the need for early targeted screening and prevention efforts that may reduce later opioid misuse. Perspective: Using a large, nationally representative sample, we found that chronic pain during adolescence was an independent risk factor for opioid misuse in adulthood, over and above other known risk factors. Furthermore, among those individuals with adolescent chronic pain, substance use, exposure to trauma, and race were associated with opioid misuse.

A direct test of the diathesis-stress model for depression

The diathesis-stress theory for depression states that the effects of stress on the depression risk are dependent on the diathesis or vulnerability, implying multiplicative interactive effects on the liability scale. We used polygenic risk scores for major depressive disorder (MDD) calculated from the results of the most recent analysis from the Psychiatric Genomics Consortium as a direct measure of the vulnerability for depression in a sample of 5221 individuals from 3083 families. In the same we also had measures of stressful life events and social support and a depression symptom score, as well as DSM-IV MDD diagnoses for most individuals. In order to estimate the variance in depression explained by the genetic vulnerability, the stressors and their interactions, we fitted linear mixed models controlling for relatedness for the whole sample as well as stratified by sex. We show a significant interaction of the polygenic risk scores with personal life events (0.12% of variance explained, P-value=0.0076) contributing positively to the risk of depression. Additionally, our results suggest possible differences in the aetiology of depression between women and men. In conclusion, our findings point to an extra risk for individuals with combined vulnerability and high number of reported personal life events beyond what would be expected from the additive contributions of these factors to the liability for depression, supporting the multiplicative diathesis-stress model for this disease.

Antidepressant effect of taurine in chronic unpredictable mild stress-induced depressive rats

Depression, a psychiatric and dysthymic disorder, severely affects the learning, work and life quality. The main pathogenesis of depression is associated with central nervous system (CNS) dysfunction. Taurine has been demonstrated to exert protective effects on the brain development and can improve learning ability and memory. Our study investigated the antidepressant-like effects of taurine pre-treatment by examining the changes in depression-like behavior, hormones, neurotransmitters, inflammatory factors and neurotrophic factors in the hippocampus of a chronic unpredictable mild stress (CUMS)-induced depressive rat model. Taurine was found to inhibit the decrease of sucrose consumption and prevent the deficiency of spatial memory and anxiety in rats exposed to CUMS, suggesting a preventive effect of taurine on depression-like behavior. Furthermore, the decreased levels of 5-hydroxytryptamine, dopamine, noradrenaline; the increased levels of glutamate, corticosterone; and the decreased expressions of fibroblast growth factor-2, vascular endothelial growth factor and brain derived neurotrophic factor in depressive rats were hindered by taurine pre-administration. However, tumor necrosis factor-α and interleukin-1β levels were not significantly changed by taurine. The results demonstrated that the anti-depressive effect of taurine may be involved in the regulation of hypothalamic-pituitary-adrenal (HPA) axis and the promotion of neurogenesis, neuronal survival and growth in the hippocampus.