Mental and physical distress is modulated by a polymorphism in the 5-HT transporter gene interacting with social stressors and chronic disease burden

An example of a potential predictive model for psychological distress among nursing staff members

BackgroundNursing is considered a hard job and the stressors associated with this work can have negative effects on life satisfaction, quality of life and mental health.ObjectivesThe study aimed to develop a potential predictive model to identify the main factors influencing nurses' mental health, focusing on personal characteristics, working conditions, quality of life, and life satisfaction.MethodsThis cross-sectional study was focused on a sample of nurses at university hospital center in Sfax-Tunisia. Validated self-reporting instruments were used: Satisfaction With Life Scale (SWLS), World Health Organization Quality Of Life - BREF (WHOQOL-BREF) and General Health Questionnaire (GHQ 28). Statistical software R was used to perform the statistical analyses.ResultsThe survey included 199 nurses. The average GHQ-28 score was 27.3 ± 12.4. The predictive model identified the following significant predictors of psychological distress: female gender (β = 0.54, p < 0.001), presence of a chronic disease (β = 0.56, p < 0.001), bad financial status (β = 0.54, p < 0.001), and life satisfaction score (β = -0.6, p < 0.001), collectively explaining 40% of the variance in the total GHQ 28 score.ConclusionThese findings indicate that interventions promoting the mental health of nurses could be implemented by improving modifiable predictors such as physical health and life satisfaction.

Similarities and Differences of Mental Health in Women and Men: A Systematic Review of Findings in Three Large German Cohorts

In Germany, large, population-based cohort studies have been implemented in order to identify risk and protective factors for maintaining health across the life span. The purpose of this systematic review is to analyse findings from three large ongoing cohorts and to identify sex-specific prevalence rates, risk and protective factors for mental health. Published studies from the Cooperative Health Research in the Region Augsburg (KORA), the Study of Health in Pomerania (SHIP) and the Gutenberg Health Study (GHS)), representing the southern, north-eastern and middle parts of Germany, were identified through searches of the databases PubMed and Web of Science. A total of 52 articles was identified from the start of each cohort until June 2019. Articles reporting prevalence rates of mental health [N = 22], explanatory factors for mental health [N = 25], or both [N = 5] were identified. Consistent across cohorts, higher prevalence rates of internalizing disorders were found for women and more externalizing disorders for men. Risk and protective factors for mental health included social factors, lifestyle, physical health, body mass index (BMI), diabetes, genetic and biological factors. In all areas, differences and similarities were found between women and men. The most evident were the sex-specific risk profiles for depression with mostly external risk factors for men and internal risk factors for women. Gender was not assessed directly, therefore we examined whether socioeconomic and family-related factors reflecting gender roles or institutionalized gender could be used as a proxy for gender. Overall, this systematic review shows differences and similarities in prevalence rates and determinants of mental health indicators between women and men. They underline the importance of focussing on sex specific approaches in mental health research and in the development of prevention measures. Current research on mental health still lacks focus on gender aspects. Therefore, an increased focus on sex and gender in mental health research is of great importance.

Vitamin D moderates the interaction between 5-HTTLPR and childhood abuse in depressive disorders

A complex interplay between genetic and environmental factors determines the individual risk of depressive disorders. Vitamin D has been shown to stimulate the expression of the tryptophan hydroxylase 2 (TPH2) gene, which is the rate-limiting enzyme for serotonin production in the brain. Therefore, we investigate the hypothesis that serum vitamin D levels moderate the interaction between the serotonin transporter promotor gene polymorphism (5-HTTLPR) and childhood abuse in depressive disorders. Two independent samples from the Study of Health in Pomerania (SHIP-LEGEND: n = 1 997; SHIP-TREND-0: n = 2 939) were used. Depressive disorders were assessed using questionnaires (BDI-II, PHQ-9) and interview procedures (DSM-IV). Besides serum vitamin D levels (25(OH)D), a functional polymorphism (rs4588) of the vitamin D-binding protein is used as a proxy for 25(OH)D. S-allele carriers with childhood abuse and low 25(OH)D levels have a higher mean BDI-II score (13.25) than those with a higher 25(OH)D level (9.56), which was not observed in abused LL-carriers. This significant three-way interaction was replicated in individuals with lifetime major depressive disorders when using the rs4588 instead of 25(OH)D (p = 0.0076 in the combined sample). We conclude that vitamin D relevantly moderates the interaction between childhood abuse and the serotonergic system, thereby impacting vulnerability to depressive disorders.

[The application of the BL-38 subjective complaints scale in an epidemiological cohort study (Study of Health in Pomerania)]

The application of the BL-38 subjective complaints scale in an epidemiological cohort study (Study of Health in Pomerania) Objective: We provide an overview of the application of the BL-38 complaints scale in the epidemiological Study of Health in Pomerania. We examine the influence of socio-demographic variables on complaint burden and the stability of complaint burden over time. Methods: 16 studies that used the BL-38 in analyses of SHIP-data were examined in terms of how the BL-38 was operationalised and the statistically significant results yielded. We conduct linear regression analyses to assess effects of sociodemographic variables on complaint burden in four SHIP populations and assess test-retest-reliability over a 17-year period. Results: The BL-38 is predominantly used flexibly to depict specific complaints in analyses covering a heterogeneous range of disciplines and study questions. Total, somatic and mental complaint burden have different determinant, predictive and confounding effects. Test-retest-reliability was moderate. Conclusions: The BL-38 allows consideration of (specified) health complaint patterns across many research disciplines. Cross-sectional and longitudinal reproducibility of significant results underlines its validity. The results underscore the importance of subjective health complaints in epidemiological and psychosomatic research.

Recovery of menses after functional hypothalamic amenorrhoea: if, when and why

BACKGROUND

Prolonged amenorrhoea occurs as a consequence of functional hypothalamic amenorrhoea (FHA) which is most often induced by weight loss, vigorous exercise or emotional stress. Unfortunately, removal of these triggers does not always result in the return of menses. The prevalence and conditions underlying the timing of return of menses vary strongly and some women report amenorrhoea several years after having achieved and maintained normal weight and/or energy balance. A better understanding of these factors would also allow improved counselling in the context of infertility. Although BMI, percentage body fat and hormonal parameters are known to be involved in the initiation of the menstrual cycle, their role in the physiology of return of menses is currently poorly understood. We summarise here the current knowledge on the epidemiology and physiology of return of menses.

OBJECTIVE AND RATIONALE

The aim of this review was to provide an overview of (i) factors determining the recovery of menses and its timing, (ii) how such factors may exert their physiological effects and (iii) whether there are useful therapeutic options to induce recovery.

SEARCH METHODS

We searched articles published in English, French or German language containing keywords related to return of menses after FHA published in PubMed between 1966 and February 2020. Manuscripts reporting data on either the epidemiology or the physiology of recovery of menses were included and bibliographies were reviewed for further relevant literature. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria served to assess quality of observational studies.

OUTCOMES

Few studies investigate return of menses and most of them have serious qualitative and methodological limitations. These include (i) the lack of precise definitions for FHA or resumption of menses, (ii) the use of short observation periods with unsatisfactory descriptions and (iii) the inclusion of poorly characterised small study groups. The comparison of studies is further hampered by very inhomogeneous study designs. Consequently, the exact prevalence of resumption of menses after FHA is unknown. Also, the timepoint of return of menses varies strongly and reliable prediction models are lacking. While weight, body fat and energy availability are associated with the return of menses, psychological factors also have a strong impact on the menstrual cycle and on behaviour known to increase the risk of FHA. Drug therapies with metreleptin or naltrexone might represent further opportunities to increase the chances of return of menses, but these require further evaluation.

WIDER IMPLICATIONS

Although knowledge on the physiology of return of menses is presently rudimentary, the available data indicate the importance of BMI/weight (gain), energy balance and mental health. The physiological processes and genetics underlying the impact of these factors on the return of menses require further research. Larger prospective studies are necessary to identify clinical parameters for accurate prediction of return of menses as well as reliable therapeutic options.

Threat-Avoidance Tendencies Moderate the Link Between Serotonin Transporter Genetic Variation and Reactive Aggression

The short (S) allele of the serotonin transporter-linked promoter region (5-HTTLPR) polymorphism has been linked to reactive aggression in men, but this association is less consistent in females. Reactive aggression has been particularly described as a result of fear-driven defense to threat, but how this interaction between defensive behavior and aggression is expressed in S-allele carriers remains unknown. In order to explore this interplay between 5-HTTLPR genotype, defensive behavior and reactive aggression, we combined genotyping with objective measures of action tendencies toward angry faces in an approach-avoidance task (AAT) and reactive aggression in the Taylor aggression paradigm (TAP) in healthy females, N = 95. This study shows that female S-allele carriers in general display increased implicit reactive aggression (administering aversive white noise) toward opponents. Furthermore, we found that threat-avoidance tendencies moderate the association between 5-HTTLPR genotype and aggression displayed on the TAP. Together, these findings indicate a positive correlation between avoidance of angry faces in the AAT and reactive aggression in the TAP exclusively present in S-allele carriers.

Genetic risk-factors for anxiety in healthy individuals: polymorphisms in genes important for the HPA axis

BACKGROUND

Two important aspects for the development of anxiety disorders are genetic predisposition and alterations in the hypothalamic-pituitary-adrenal (HPA) axis. In order to identify genetic risk-factors for anxiety, the aim of this exploratory study was to investigate possible relationships between genetic polymorphisms in genes important for the regulation and activity of the HPA axis and self-assessed anxiety in healthy individuals.

METHODS

DNA from 72 healthy participants, 37 women and 35 men, were included in the analyses. Their DNA was extracted and analysed for the following Single Nucleotide Polymorphisms (SNP)s: rs41423247 in the NR3C1 gene, rs1360780 in the FKBP5 gene, rs53576 in the OXTR gene, 5-HTTLPR in SLC6A4 gene and rs6295 in the HTR1A gene. Self-assessed anxiety was measured by the State and Trait Anxiety Inventory (STAI) questionnaire.

RESULTS

Self-assessed measure of both STAI-S and STAI-T were significantly higher in female than in male participants (p = 0.030 and p = 0.036, respectively). For SNP rs41423247 in the NR3C1 gene, there was a significant difference in females in the score for STAI-S, where carriers of the G allele had higher scores compared to the females that were homozygous for the C allele (p < 0.01). For the SNP rs53576 in the OXTR gene, there was a significant difference in males, where carriers of the A allele had higher scores in STAI-T compared to the males that were homozygous for the G allele (p < 0.01).

CONCLUSION

This study shows that SNP rs41423247 in the NR3C1 gene and SNP rs53576 in the OXTR gene are associated with self-assessed anxiety in healthy individuals in a gender-specific manner. This suggests that these SNP candidates are possible genetic risk-factors for anxiety.

Three phases of Gene × Environment interaction research: Theoretical assumptions underlying gene selection

Some Gene × Environment interaction (G×E) research has focused upon single candidate genes, whereas other related work has targeted multiple genes (e.g., polygenic scores). Each approach has informed efforts to identify individuals who are either especially vulnerable to the negative effects of contextual adversity (diathesis stress) or especially susceptible to both positive and negative contextual conditions (differential susceptibility). A critical step in all such molecular G×E research is the selection of genetic variants thought to moderate environmental influences, a subject that has not received a great deal of attention in critiques of G×E research (beyond the observation of small effects of individual genes). Here we conceptually distinguish three phases of G×E work based on the selection of genes presumed to moderate environmental effects and the theoretical basis of such decisions: (a) single candidate genes, (b) composited (multiple) candidate genes, and (c) GWAS-derived polygenic scores. This illustrative, not exhaustive, review makes it clear that implicit or explicit theoretical assumptions inform gene selection in ways that have not been clearly articulated or fully appreciated.

Effects of chronic exposure to selenomethionine on social learning outcomes in zebrafish (Danio rerio): serotonergic dysregulation and oxidative stress in the brain

For many species, social learning is crucial for fitness-related activities, but human-induced environmental changes can impair such learning processes. For instance, mining can release the element, selenium (Se), that is vital for physiological functions but also has toxicological properties at elevated concentrations. In this study, we investigated the effects of chronic exposure to Se on social learning outcomes and potential underlying molecular mechanisms in adult zebrafish. After exposure to different levels of dietary selenomethionine (control, 3.6, 12.8, 34.1 μg Se/g dry weight) for 90 days, we examined the ability of observer fish to follow demonstrators (experienced individuals) in escaping an oncoming trawl. Social learning outcomes were then assessed in the absence of demonstrators. Our results indicated that fish in the highest exposure group (34.1 μg/g) displayed significantly slower escape responses compared to fish in the control and lower exposure groups (3.6 and 12.8 μg Se/g). This impaired behavior was associated with higher oxidative stress and dysregulation in genes that are key in the serotonergic pathway, indicating that oxidative stress and alteration in the serotonergic system lead to impairment of social learning.

Constitutive Serotonin Transporter Reduction Resembles Maternal Separation with Regard to Stress-Related Gene Expression

Interactive effects between allelic variants of the serotonin transporter (5-HTT) promoter-linked polymorphic region (5-HTTLPR) and stressors on depression symptoms have been documented, as well as questioned, by meta-analyses. Translational models of constitutive 5-htt reduction and experimentally controlled stressors often led to inconsistent behavioral and molecular findings and often did not include females. The present study sought to investigate the effect of 5-htt genotype, maternal separation, and sex on the expression of stress-related candidate genes in the rat hippocampus and frontal cortex. The mRNA expression levels of Avp, Pomc, Crh, Crhbp, Crhr1, Bdnf, Ntrk2, Maoa, Maob, and Comt were assessed in the hippocampus and frontal cortex of 5-htt ^± and 5-htt ^+/+ male and female adult rats exposed, or not, to daily maternal separation for 180 min during the first 2 postnatal weeks. Gene- and brain region-dependent, but sex-independent, interactions between 5-htt genotype and maternal separation were found. Gene expression levels were higher in 5-htt ^+/+ rats not exposed to maternal separation compared with the other experimental groups. Maternal separation and 5-htt ^+/- genotype did not yield additive effects on gene expression. Correlative relationships, mainly positive, were observed within, but not across, brain regions in all groups except in non-maternally separated 5-htt ^+/+ rats. Gene expression patterns in the hippocampus and frontal cortex of rats exposed to maternal separation resembled the ones observed in rats with reduced 5-htt expression regardless of sex. These results suggest that floor effects of 5-htt reduction and maternal separation might explain inconsistent findings in humans and rodents.

Lifetime and 12-month prevalence estimates for mental disorders in northeastern Germany: findings from the Study of Health in Pomerania

Few epidemiological studies presented 12-month and lifetime prevalence estimates for DSM-IV mental disorders in the adult general population by sex and age up to very old age. From 2007 to 2010, DSM-IV mental disorders were assessed with the DIA-X/M-CIDI among N = 2400 participants (aged 29-89 years) from the Study of Health in Pomerania, an epidemiological study based on a two-stage stratified cluster sample randomly drawn from the adult general population in northeastern Germany. 36.3% of the sample was affected by any 12-month and 54.8% by any lifetime mental disorder. The most frequent diagnostic groups were anxiety (12-month: 14.8%, lifetime: 23.4%), substance use (12-month: 14.5%, lifetime: 25.0%), somatoform (12-month: 12.9%, lifetime: 20.4%) and depressive (12-month: 7.3%, lifetime: 18.6%) disorders. Except for substance use (higher prevalence in men) and bipolar disorders (comparable prevalence in men and women), higher 12-month and lifetime prevalence estimates were found in women vs. men. Moreover, lower 12-month and lifetime prevalence estimates were found in older (aged 60-74 or 75-89 years) vs. younger (aged 29-44 or 45-59 years) age groups. 22.6% (men: 21.1%, women: 23.9%) of those affected by any 12-month disorder met criteria for two and 13.6% (men: 9.6%, women: 16.9%) for three or more 12-month diagnoses. Similarly, 26.4% (men: 25.7%, women: 26.9%) of those affected by any lifetime disorder met criteria for two and 22.7% (men: 19.6%, women: 25.2%) for three or more lifetime diagnoses. Our findings demonstrate the frequency of mental disorders in northeastern Germany and emphasize the need for continued prevention and intervention efforts.

Prospective associations of androgens and sex hormone-binding globulin with 12-month, lifetime and incident anxiety and depressive disorders in men and women from the general population

BACKGROUND

Findings on associations of androgens and sex hormone-binding globulin (SHBG) with anxiety and depressive disorders in the general population remain inconclusive.

METHODS

We used data of n = 993 men and n = 980 women from the Study of Health in Pomerania (SHIP, a prospective-longitudinal general population study from northeastern Germany). Immunoassay-measured serum concentrations of total testosterone, androstenedione and SHBG were assessed when participants were aged 20-80. 12-month, lifetime and incident DSM-IV anxiety and depressive disorders were assessed with the DIA-X/M-CIDI at 10-year follow-up, when participants were aged 29-89. Logistic regressions were adjusted for age, smoking, alcohol consumption, physical activity, waist circumference, hypertension and oral contraceptive use (women only) at baseline and follow-up interval.

RESULTS

In men and women, androgens and SHBG were not associated significantly with incident anxiety and depressive disorders. In men, higher total testosterone predicted any 12-month (OR = 1.46) and lifetime (OR = 1.34) anxiety disorder, lifetime social phobia (OR = 2.15), and 12-month (OR = 1.48) and lifetime (OR = 1.39) specific phobia, but neither 12-month nor lifetime depression. Moreover, androstenedione in men interacted with age in predicting lifetime anxiety disorders (OR = 0.98): Higher androstenedione more strongly predicted lifetime anxiety in younger vs. older men. These findings, however, did not survive correction for multiple testing. In women, androgens and SHBG were not associated significantly with 12-month and lifetime anxiety and depressive disorders.

LIMITATIONS

The follow-up period was relatively long and other factors might have affected the examined associations.

CONCLUSIONS

Higher serum total testosterone in men and androstenedione in younger men may relate to an increased risk of anxiety disorders.

CACNA1C rs1006737, Threatening Life Events, and Gene-Environment Interaction Predict Major Depressive Disorder

INTRODUCTION

CACNA1C rs1006737 is a novel variant in discovery of replicable associations in major depressive disorder (MDD). However, there have been no specific studies considered effect of environmental pathogens to date examining its clinical significance. In this study we investigated the interaction effect between CACNA1C rs1006737 polymorphism and threatening life events (TLEs) in MDD and carried out a meta-analysis of published findings.

METHODS

A total of 1,177 consecutive participants were genotyped. Information on exposure to TLEs, socio-demographic data, and history of psychological problems among first-degree relatives was collected. MDD was diagnosed according to the Chinese version of the 24-item Hamilton Rating Scale for Depression.

RESULTS

There was a significant interaction effect between CACNA1C rs1006737 polymorphism and TLEs in MDD. A dose-response relationship was found between CACNA1C rs1006737 genotypes and TLEs in MDD. The results of the meta-analysis showed that CACNA1C rs1006737 genotypes interacted with TLEs in MDD.

CONCLUSION

CACNA1C rs1006737 genotype and previous exposure to TLEs interact to influence the risk of developing MDD. We propose that CACNA1C rs1006737 may represent a target for novel pharmacological therapies to prevent or treat MDD.

High Thyrotropin Is Associated with Reduced Hippocampal Volume in a Population-Based Study from Germany

BACKGROUND

Previous patient studies suggest that thyroid dysfunction affects volumes of particular regions of the brain. So far, population-based data related to this topic are lacking. The aim of this study was to investigate associations of serum levels of thyrotropin (TSH), free triiodothyronine, and free thyroxine (fT4) with total brain volume, gray matter volume, white matter volume (WMV), and hippocampal volume (HV) in a population-based study.

METHODS

Data on 2557 individuals were pooled from two independent population-based surveys of the Study of Health in Pomerania conducted in Northeast Germany. Brain volumes were determined from images derived from 1.5 T magnetic resonance imaging. Low and high TSH were defined using the cutoffs 0.40 and 3.29 mIU/L, respectively. Associations between thyroid hormone levels and segmented brain volumes were analyzed by linear regression models. Further, voxel-based morphometry was conducted to search for associations with thyroid hormone levels in a hypothesis-free way throughout the whole brain. All models were adjusted for confounders.

RESULTS

Only 9/70 individuals with high TSH had low free triiodothyronine or fT4 levels. Individuals with high TSH had significantly lower total brain volume (β = -26.9 [confidence interval (CI) -49.0 to -4.8]; p = 0.017), WMV (β = -16.1 [CI -29.4 to -2.7]; p = 0.018), and HV (β = -223 [CI -395 to -50]; p = 0.011) than individuals with TSH within the reference range, while low TSH was not significantly associated with any of the brain volumes. Voxel-based morphometry analyses revealed a significant positive association with serum fT4 levels in the left middle frontal gyrus.

CONCLUSIONS

In conclusion, the results of this study indicate that the subclinical hypothyroid state may lead to a reduced brain volume affecting particularly HV in younger subjects and WMV, which might correspond to subtle microstructural changes in white matter fiber tracts or myelination of the axones. Gray matter seems not to be affected by subclinical hypothyroid states.

Interplay between RGS2 and childhood adversities in predicting anxiety and depressive disorders: Findings from a general population sample

BACKGROUND

It remains unresolved whether childhood adversities interact with genetic variation in regulator of G-protein signaling 2 (RGS2) rs4606 in predicting various anxiety and depressive disorders and whether diagnostic specificity exists in these interactions.

METHODS

The genotype of RGS2 rs4606 was determined for N = 2,263 adults with European ancestry from the Study of Health in Pomerania. Lifetime anxiety and depressive disorders according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, were assessed with the Munich Composite International Diagnostic Interview (DIA-X/M-CIDI). Childhood adversities were assessed with the Childhood Trauma Questionnaire (CTQ, when participants were aged 29-89).

RESULTS

Logistic regressions adjusted for sex and age revealed that rs4606 interacted with total childhood adversity in predicting each diagnostic outcome except for panic disorder and generalized anxiety disorder, uncorrected and corrected for multiple testing (odds ratio [OR] = 1.06-1.16). That is, carriers of the GG (vs. CC/CG) genotype were at decreased risk for anxiety and/or depression in the presence of low, but at increased risk in the presence of high total childhood adversity. Respective gene-environment (G × E) interactions were found for (a) comorbid anxiety and depressive disorders (OR = 1.13), but neither pure anxiety nor pure depressive disorders and (b) pure/temporally primary anxiety disorders (OR = 1.07), but not pure/temporally primary depressive disorders. The G × E interaction remained associated with depressive disorders after introducing pure/temporally primary anxiety disorders as additional predictor (OR = 1.09).

CONCLUSIONS

rs4606 alters the risk of developing a range of anxiety but also depressive disorders after childhood adversities. A complex risk pattern of genotype, environmental factors, and preexisting anxiety contributes to subsequent depression development.

Dating violence victimization and substance use: The role of a serotonin transporter gene polymorphism (5HTTLPR)

While there is developing research on how genes moderate the effect of stressful life events on substance use, the limited research has yet to focus on specific stressors. As adolescent dating violence victimization has been linked to various substance use behaviors, the current research seeks to further examine the longitudinal outcomes of adolescent dating violence victimization and the role that genes play in moderating these effects. Specifically, using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a series of logistic and negative binomial regressions are run to analyze the direct and interactive effects of adolescent dating violence victimization and a polymorphism (5HTTLPR) in the promoter region of the serotonin transporter gene on both alcohol use problems and marijuana use. The results find that 5HTTLPR interacts with adolescent dating violence victimization to increase odds of marijuana use for the sample. However, the interaction between 5HTTLPR and adolescent dating violence has differential effects for males and females, suggesting sex differences regarding the susceptibility properties of 5HTTLPR. Implications of these findings are discussed.

Interplay between COMT Val158Met, childhood adversities and sex in predicting panic pathology: Findings from a general population sample

BACKGROUND

The single nucleotide polymorphism rs4680 of the catechol-O-methyltransferase (COMT) gene has been implicated to be involved in the etiopathogenesis of panic. However, it remains unresolved whether rs4680 modifies the risk-association between early life stress and subsequent development of panic pathology.

METHODS

The genotype of rs4680 was determined for n = 2242 adults with European ancestry from the Study of Health in Pomerania (SHIP, a regional longitudinal cohort study from northeastern Germany). Lifetime fearful spells, panic attacks and panic disorder were assessed according to DSM-IV in 2007-2010 (when participants were aged 29-89) using the Munich Composite International Diagnostic Interview (DIA-X/M-CIDI). Childhood adversities were assessed with the Childhood Trauma Questionnaire (CTQ).

RESULTS

Logistic regressions with interaction terms (adjusted for sex and age) revealed that rs4680 interacted with total childhood adversity, emotional abuse and physical abuse in predicting panic disorder: Respective childhood adversities predicted panic disorder in carriers of the Val/Met or Met/Met genotype, but not Val/Val genotype. Moreover, a 3-way interaction was found between rs4680, emotional abuse and sex in predicting panic attacks: Emotional abuse predicted panic attacks among male carriers of the Val/Val genotype and female carriers of the Val/Met or Met/Met genotype, but not among male carriers of the Val/Met or Met/Met genotype or female carriers of the Val/Val genotype.

LIMITATIONS

Genotype data were derived by imputation. Childhood adversities and panic were assessed retrospectively.

CONCLUSIONS

Especially (female) carriers of the Val/Met or Met/Met genotype of rs4680 might profit from targeted early interventions to prevent the onset of panic after childhood adversities.

Association of Brain-Derived Neurotrophic Factor and Vitamin D with Depression and Obesity: A Population-Based Study

BACKGROUND

Depression and obesity are widespread and closely linked. Brain-derived neurotrophic factor (BDNF) and vitamin D are both assumed to be associated with depression and obesity. Little is known about the interplay between vitamin D and BDNF. We explored the putative associations and interactions between serum BDNF and vitamin D levels with depressive symptoms and abdominal obesity in a large population-based cohort.

METHODS

Data were obtained from the population-based Study of Health in Pomerania (SHIP)-Trend (n = 3,926). The associations of serum BDNF and vitamin D levels with depressive symptoms (measured using the Patient Health Questionnaire) were assessed with binary and multinomial logistic regression models. The associations of serum BDNF and vitamin D levels with obesity (measured by the waist-to-hip ratio [WHR]) were assessed with binary logistic and linear regression models with restricted cubic splines.

RESULTS

Logistic regression models revealed inverse associations of vitamin D with depression (OR = 0.966; 95% CI 0.951-0.981) and obesity (OR = 0.976; 95% CI 0.967-0.985). No linear association of serum BDNF with depression or obesity was found. However, linear regression models revealed a U-shaped association of BDNF with WHR (p < 0.001).

CONCLUSION

Vitamin D was inversely associated with depression and obesity. BDNF was associated with abdominal obesity, but not with depression. At the population level, our results support the relevant roles of vitamin D and BDNF in mental and physical health-related outcomes.

FoxO1, A2M, and TGF-β1: three novel genes predicting depression in gene X environment interactions are identified using cross-species and cross-tissues transcriptomic and miRNomic analyses

To date, gene-environment (GxE) interaction studies in depression have been limited to hypothesis-based candidate genes, since genome-wide (GWAS)-based GxE interaction studies would require enormous datasets with genetics, environmental, and clinical variables. We used a novel, cross-species and cross-tissues "omics" approach to identify genes predicting depression in response to stress in GxE interactions. We integrated the transcriptome and miRNome profiles from the hippocampus of adult rats exposed to prenatal stress (PNS) with transcriptome data obtained from blood mRNA of adult humans exposed to early life trauma, using a stringent statistical analyses pathway. Network analysis of the integrated gene lists identified the Forkhead box protein O1 (FoxO1), Alpha-2-Macroglobulin (A2M), and Transforming Growth Factor Beta 1 (TGF-β1) as candidates to be tested for GxE interactions, in two GWAS samples of adults either with a range of childhood traumatic experiences (Grady Study Project, Atlanta, USA) or with separation from parents in childhood only (Helsinki Birth Cohort Study, Finland). After correction for multiple testing, a meta-analysis across both samples confirmed six FoxO1 SNPs showing significant GxE interactions with early life emotional stress in predicting depressive symptoms. Moreover, in vitro experiments in a human hippocampal progenitor cell line confirmed a functional role of FoxO1 in stress responsivity. In secondary analyses, A2M and TGF-β1 showed significant GxE interactions with emotional, physical, and sexual abuse in the Grady Study. We therefore provide a successful 'hypothesis-free' approach for the identification and prioritization of candidate genes for GxE interaction studies that can be investigated in GWAS datasets.

Association between serum neuron-specific enolase, age, overweight, and structural MRI patterns in 901 subjects

Serum neuron-specific enolase (sNSE) is considered a marker for neuronal damage, related to gray matter structures. Previous studies indicated its potential as marker for structural and functional damage in conditions with adverse effects to the brain like obesity and dementia. In the present study, we investigated the putative association between sNSE levels, body mass index (BMI), total gray matter volume (GMV), and magnetic resonance imaging-based indices of aging as well as Alzheimer's disease (AD)-like patterns.

SUBJECTS/METHODS

sNSE was determined in 901 subjects (499 women, 22-81 years, BMI 18-48 kg/m²), participating in a population-based study (SHIP-TREND). We report age-specific patterns of sNSE levels between males and females. Females showed augmenting, males decreasing sNSE levels associated with age (males: p = 0.1052, females: p = 0.0363). sNSE levels and BMI were non-linearly associated, showing a parabolic association and decreasing sNSE levels at BMI values >25 (p = 0.0056). In contrast to our hypotheses, sNSE levels were not associated with total GMV, aging, or AD-like patterns. Pathomechanisms discussed are: sex-specific hormonal differences, neuronal damage/differentiation, or impaired cerebral glucose metabolism. We assume a sex-dependence of age-related effects to the brain. Further, we propose in accordance to previous studies an actual neuronal damage in the early stages of obesity. However, with progression of overweight, we assume more profound effects of excess body fat to the brain.

Sex differences modulating serotonergic polymorphisms implicated in the mechanistic pathways of risk for depression and related disorders

Despite consistent observations of sex differences in depression and related emotional disorders, we do not yet know how these sex differences modulate the effects of genetic polymorphisms implicated in risk for these disorders. This Mini-Review focuses on genetic polymorphisms of the serotonergic system to illustrate how sex differences might modulate the neurobiological pathways involved in the development of depression. We consider the interacting role of environmental factors such as early-life stress. Given limited current knowledge about this topic, we highlight methodological considerations, challenges, and guidelines for future research. © 2016 Wiley Periodicals, Inc.

Stress Processes Linking Parent-Child Disconnection to Disease Risk in Young Adulthood: Amplification by Genotype

Previous studies have documented that early stressful family relationships influence subsequent stressful life circumstances and health outcomes over the life course. Less is known, however, about whether stressful parent-child relationships increase the influence of proximal stressors on youth health operating as a stress-sensitizing life context, and individual genetic variations have effects on these developmental processes. Informed by life course stress process theory, which focuses on the proliferation, accumulation, and interactions of stressors over the life course as health risks, we examined whether (a) parent-child disconnection influences the occurrence of stressful life events in young adulthood, (b) parent-child disconnection potentiates the impact of stressful life events on young adults' health, or (c) potential health impact is intensified further by individual genotype. Using longitudinal data from a nationally representative sample of 11,290 adolescents (Mean age 15.5 years, 53% female) over a period of 13 years, we found parent-child disconnection influenced young adults' stressful life events and amplified the impact of stressful life events on cardio-metabolic disease risk. We also found the association between stressful life events and cardio-metabolic disease risk was further intensified by the 5-HTTLPR polymorphism. Our findings demonstrate that stressful family relationships not only initiate stress processes over the early life course, but also sensitize youth to stressors, and that 5-HTTLPR polymorphism interacts with stressful life experiences to predict heightened disease risk.

Sex- and age-specific associations between major depressive disorder and metabolic syndrome in two general population samples in Germany

BACKGROUND AND AIMS

Major depressive disorder (MDD) has been associated with the Metabolic Syndrome (MetS). As previous data strongly suggested sex and age effects on this association, this study aimed to analyse the association between MDD and MetS in two general population samples under explicit consideration of sex and age.

METHODS

This study analysed cross-sectional data based on two independent general population samples: SHIP-0 (n = 4083; 20-81 years; 49.4% male) and SHIP-TREND-0 (n = 3957; 20-83 years; 49.0% male) that were part of the Study of Health in Pomerania. MDD (SHIP-0: 12.6%; SHIP-TREND-0: 27.2%) was assessed using the Composite International Diagnostic-Screener (CID-S) in both samples. Interview assessment of MDD diagnosis according to Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) criteria was performed in SHIP-TREND-0 (18.1% MDD). MetS was defined by abdominal obesity, elevated blood pressure, elevated glucose, elevated triglycerides and reduced high-density lipoprotein cholesterol according to established criteria. Data analysis was performed sex- and age-stratified.

RESULTS

Prevalence of MetS was high in both samples: 19.4% of females and 30.2% of males in SHIP-0 and 22.1% and 33.2% in SHIP-TREND-0, respectively. Effect modifications were observed by sex and age on the association between MDD and MetS. Particularly, younger females (20-49 years) with MDD were more often affected by MetS than younger females without MDD: OR = 2.21 (95% CI = 1.39-3.50). This association vanished in elderly participants (50-82 years).

CONCLUSION

The data suggest that especially younger (presumably pre-menopausal) females with MDD are more likely to have MetS than those without major depressive disorders, and that age extenuates this association.

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)

Background

The low transcriptionally efficient short-allele of the 5HTTLPR serotonin transporter polymorphism has been implicated to moderate the relationship between the experience of stressful life events (SLEs) and depression. Despite numerous attempts at replicating this observation, results remain inconclusive.

Methods

We examined this relationship in young-adult Non-Hispanic white males and females between the ages of 22 and 26 (n = 4724) participating in the National Longitudinal Study of Adolescent to Adult Health (Add Health) with follow-up information every six years since 1995.

Results

Linear and logistic regression models, corrected for multiple testing, indicated that carriers of one or more of the S-alleles were more sensitive to stress than those with two L-alleles and at a higher risk for depression. This relationship behaved in a dose-response manner such that the risk for depression was greatest among those who reported experiencing higher numbers of SLEs. In post-hoc analyses we were not able to replicate an interaction effect for suicide ideation but did find suggestive evidence that the effects of SLEs and 5HTTLPR on suicide ideation differed for males and females. There were no effects of childhood maltreatment.

Discussion

Our results provide partial support for the original hypothesis that 5-HTTLPR genotype interacts with the experience of stressful life events in the etiology of depression during young adulthood. However, even with this large sample, and a carefully constructed a priori analysis plan, the results were still not definitive. For the purposes of replication, characterizing the 5HTTLPR in other large data sets with extensive environmental and depression measures is needed.

Association between the 5-HTTLPR Genotype and Childhood Characteristics in Mood Disorders

Objective

The features of childhood attention deficit hyperactivity disorder (ADHD) are significantly associated with adult mood disorders. Some genetic factors may be common to both ADHD and mood disorders underlie the association between these two phenotypes. The present study aimed to determine whether a genetic role may be played by the serotonin transporter-linked polymorphic region (5-HTTLPR) in the childhood ADHD features of adult patients with mood disorders.

Methods

The present study included 232 patients with major depressive disorder (MDD), 154 patients with bipolar disorder (BPD), and 1,288 normal controls. Childhood ADHD features were assessed with the Korean version of the Wender Utah Rating Scale (WURS-K). The total score and the scores of three factors (impulsivity, inattention, and mood instability) from the WURS-K were analyzed to determine whether they were associated with the 5-HTTLPR genotype.

Results

In the BPD type II group, the 5-HTTLPR genotype was significantly associated with the total score (p=0.029) and the impulsivity factor (p=0.004) on the WURS-K. However, the inattention and mood instability factors were not associated with the 5-HTTLPR genotype. BPD type I, MDD and normal control groups did not exhibit any significant associations between the WURS-K scores and the 5-HTTLPR genotype.

Conclusion

The findings suggest that the 5-HTTLPR genotype may play a role in the impulsivity component of childhood ADHD in patients with BPD type II. Because of a small sample size and a single candidate gene, further studies investigating other candidate genes using a larger sample are warranted to determine any common genetic links.

5-HTTLPR and gender differences in affective disorders: A systematic review

BACKGROUND

Serotonin transporter-linked polymorphic region (5-HTTLPR) variants have been extensively studied in psychiatric disorders. Although gender effects have been reported, they have not been comprehensively reviewed. The aim of our study was to summarize literature findings on 5-HTTLPR and gender differences in affective disorders.

METHODS

A systematic search of PubMed, ISI Web of Knowledge, and PsycINFO databases was performed for dates until January 2015. The included articles (n=78) analyzed the association between 5-HTTLPR and affective spectrum disorders, taking into account gender. The quality of each study was assessed through STROBE and CONSORT.

RESULTS

5-HTTLPR modulation of affective disorders varied by gender. The S allele (or SS genotype) seemed to be differently associated with an increased risk of depression, depressive symptoms, anxiety traits and symptoms, and symptoms of internalizing behavior among women and an increased risk of aggressiveness, conduct disorder and symptom counts of externalizing behavior among men. Moreover, the presence of stressful life events reinforced the association. Interestingly, these differences seemed to begin with adolescence and were not consistent among the elderly, suggesting a plausible role of hormonal fluctuations.

LIMITATIONS

The review is limited by the small number of included papers, due to the paucity of information in the literature regarding 5-HTTLPR and gender.

CONCLUSIONS

5-HTTLPR variants may exert a differential modulation on a number of features depending on gender. Further studies are needed to more deeply investigate the effect of 5-HTTLPR×gender on the modulation of affective disorders.

Influence of Serotonin Transporter Gene Polymorphisms and Adverse Life Events on Depressive Symptoms in the Elderly: A Population-Based Study

Background

Depression is common in the elderly. The role of genetic and environmental factors in modulating depressive symptoms is not clear.

Methods

We evaluated the influence of serotonin transporter gene polymorphisms and recent adverse life events on depressive symptoms in an elderly Italian population. We used data from “InveCe.Ab”, a population-based study of 1321 subjects aged 70–74 years. We used the 15-item Geriatric Depression Scale (GDS) to assess depressive symptoms–a GDS score ≥5 points (GDS≥5) indicated the presence of clinically relevant symptoms–and performed 5-HTTLPR and rs25531 genotyping to obtain the triallelic polymorphism of the serotonin transporter. We used the Geriatric Adverse Life Events Scale to measure adverse life events, and logistic regression models to evaluate the role of genotype and recent adverse life events in depressive symptoms, controlling for potential confounders and independent predictors.

Results

Two hundred subjects (15.76%) had a GDS≥5. The 5-HTTLPR triallelic polymorphism was significantly associated with GDS≥5. Only S′S′ carriers showed an increased risk of depressive symptoms (OR_adj = 1.81, p = .022); one extra adverse life event increased this risk by 14% (p = .061) independently of genotype. Other factors significantly related to GDS≥5 were: female gender (OR_adj = 2.49, p < .001), age (OR_adj = 1.19, p = .007), a history of depression (OR_adj = 4.73, p < .001), and comorbidity (OR_adj = 1.23, p = .001). One extra adverse life event increased the risk of depressive symptoms by 57% (p = .005) only in the L′L′ carriers, while antidepressant intake was directly related to GDS≥5 in the L′S′ carriers (OR_adj = 2.46, p = .036) and borderline significant in the S′S′ carriers (OR_adj = 2.41, p = .081).

Discussion

The S′S′ genotype and recent exposure to adverse life events were independently associated with depressive symptoms. The S′S′ genotype, compared with the environment, exerted a predominant effect on depressive symptoms, suggesting that it reduces the efficacy of antidepressant therapy. We conclude that genetics may be an important risk factor for depressive symptoms in late adulthood.

Effects of Recent Stress and Variation in the Serotonin Transporter Polymorphism (5-HTTLPR) on Depressive Symptoms: A Repeated-Measures Study of Adults Age 50 and Older

Depending on genetic sensitivity to it, stress may affect depressive symptomatology differentially. Applying the stress-diathesis hypothesis to older adults, we postulate: (1) recent stress will associate with increased depressive symptom levels and (2) this effect will be greater for individuals with at least one short allele of the serotonin transporter gene promoter region (5-HTTLPR). Further, we employ a design that addresses specific limitations of many prior studies that have examined the 5-HTTLPR × SLE relation, by: (a) using a within-person repeated-measures design to address fluctuations that occur within individuals over time, increase power for detecting G × E, and address GE correlation; (b) studying reports of exogenous stressful events (those unlikely to be caused by depression) to help rule out reverse causation and negativity bias, and in order to assess stressors that are more etiologically relevant to depressive symptomatology in older adults. The sample is drawn from the Health and Retirement Study, a U.S. population-based study of older individuals (N = 28,248; mean age = 67.5; 57.3 % female; 80.7 % Non-Hispanic White, 14.9 % Hispanic/Latino, 4.5 % African American; genetic subsample = 12,332), from whom measures of depressive symptoms and exogenous stressors were collected biannually (1994-2010). Variation in the 5-HTTLPR was characterized via haplotype, using two single nucleotide polymorphisms (SNPs). Ordered logit models were constructed to predict levels of depressive symptoms from 5-HTTLPR and stressors, comparing results of the most commonly applied statistical approaches (i.e., comparing allelic and genotypic models, and continuous and categorical predictors) used in the literature. All models were stratified by race/ethnicity. Overall, results show a main effect of recent stress for all ethnic groups, and mixed results for the variation in 5-HTTLPR × stress interaction, contingent upon statistical model used. Findings suggest there may be a differential effect of stressors and 5-HTTLPR on depressive symptoms by ethnicity, but further research is needed, particularly when using a haplotype to characterize variation in 5-HTTLPR in population-based sample with a diverse ethnic composition.

Association between waist circumference and gray matter volume in 2344 individuals from two adult community-based samples

We analyzed the putative association between abdominal obesity (measured in waist circumference) and gray matter volume (Study of Health in Pomerania: SHIP-2, N=758) adjusted for age and gender by applying volumetric analysis and voxel-based morphometry (VBM) with VBM8 to brain magnetic resonance (MR) imaging. We sought replication in a second, independent population sample (SHIP-TREND, N=1586). In a combined analysis (SHIP-2 and SHIP-TREND) we investigated the impact of hypertension, type II diabetes and blood lipids on the association between waist circumference and gray matter. Volumetric analysis revealed a significant inverse association between waist circumference and gray matter volume. VBM in SHIP-2 indicated distinct inverse associations in the following structures for both hemispheres: frontal lobe, temporal lobes, pre- and postcentral gyrus, supplementary motor area, supramarginal gyrus, insula, cingulate gyrus, caudate nucleus, olfactory sulcus, para-/hippocampus, gyrus rectus, amygdala, globus pallidus, putamen, cerebellum, fusiform and lingual gyrus, (pre-) cuneus and thalamus. These areas were replicated in SHIP-TREND. More than 76% of the voxels with significant gray matter volume reduction in SHIP-2 were also distinct in TREND. These brain areas are involved in cognition, attention to interoceptive signals as satiety or reward and control food intake. Due to our cross-sectional design we cannot clarify the causal direction of the association. However, previous studies described an association between subjects with higher waist circumference and future cognitive decline suggesting a progressive brain alteration in obese subjects. Pathomechanisms may involve chronic inflammation, increased oxidative stress or cellular autophagy associated with obesity.

Social support and the serotonin transporter genotype (5-HTTLPR) moderate levels of resilience, sense of coherence, and depression

Gene x environment interactions have mainly been investigated in models of psychopathology. However, the putative interplay between genes and beneficial environmental conditions on positive outcomes has rarely been addressed. We therefore examined the interaction between the serotonin transporter linked polymorphic region (5-HTTLPR) and social support on the sense of coherence (SOC), resilience, and depressive symptoms. Furthermore, we scrutinized our examinations by differentiating between individuals with and without childhood abuse. The sample included 1,811 participants from the general population (Study of Health in Pomerania, Germany). The triallelic genotype of 5-HTTLPR was determined and longitudinal data of social support were used. Among individuals with high social support no significant differences between 5-HTTLPR genotypes regarding all outcome variables were found. However, among those with low social support, carriers of at least one short allele reported significantly increased levels of SOC and resilience, as well as less depressive symptoms than carriers of the l/l genotype. This result was not modified by differentiating between those with childhood abuse and those without. In less supportive social environments the impact of distinct genotypes on behavioral outcomes might be more relevant than in supportive environments where social compensation might take place. Our findings indicate that both alleles of 5-HTTLPR contribute to the adaptability to different environmental conditions.

An analysis of the influence of selected genetic and hormonal factors on the occurrence of depressive symptoms in late-reproductive-age women

BACKGROUND

The aim of this study was to analyze the influence of genetic and hormonal factors on incidences of depressive symptoms in late-reproductive-age women.

METHODS

The study was performed using the Beck Depression Inventory, the PCR, and genetic tests of 347 healthy late-reproductive-age Polish women.

RESULTS

The relationship between the level of anti-Müllerian hormone (AMH) and depressive symptoms was not statistically significant (p > 0.05). Increases in age and FSH levels were accompanied by a decrease in AMH level in a significant way (p < 0.05). There were no statistically significant relationships between the distribution of genotypes and the frequency of alleles of the investigated polymorphisms and depressive symptoms according to the Beck Depression Inventory.

CONCLUSIONS

(1) The presence of the s/s genotype of the 5-HTTLPR polymorphism in the serotonin transporter promoter region and the 3/3 genotype of the 30-bp VNTR polymorphism in the monoamine oxidase A promoter region does not contribute to the development of depressive symptoms in late-reproductive-age women. (2) A relationship between the level of anti-Müllerian hormone and depressive symptoms was not confirmed in the group of healthy late-reproductive-age women. (3) AMH level correlates negatively with FSH level and age, which confirms that AMH can be regarded as a factor reflecting the ovarian reserve.

Serotonin transporter gene × environment and risk of depression in community-treated epilepsy

OBJECTIVES

This study aimed to test whether a specific serotonin transporter (5HTT) gene polymorphism interacting with life stress increased the risk of depression in patients with epilepsy.

METHODS

The Tasmanian Epilepsy Register Mood Study (TERMS) used a cross-sectional study design of a community sample of patients with epilepsy previously recruited into the Tasmanian Epilepsy Register. It employed a mailed self-complete questionnaire and saliva DNA collection. Depression was assessed using the Center for Epidemiologic Studies Depression Scale. Environmental measures were selected to cover recent stressful events, epilepsy-related stress, current social support, and early life stress.

RESULTS

Of 820 eligible participants, 553 (67%) participants completed the study. Experience of at least one stressful life event was very common, with a significant association between depression and the stressful life events (F=26.2, df=3, p<0.001). There was no association between serotonin transporter genotype and level of depressive symptoms reported (F=0.421, df=2, p=0.7). There was no evidence of any adverse life experiences interacting with serotonin transporter genotype to moderate the risk of depression.

SIGNIFICANCE

The failure to demonstrate a main effect of genotype on depression or a gene × environment interaction differs from several studies of patients with other chronic diseases. However, it is consistent with larger general population studies.

Genetic, psychosocial and clinical factors associated with hippocampal volume in the general population

The hippocampus--crucial for memory formation, recall and mood regulation--is involved in the pathophysiology of dementia and depressive disorders. Recent genome-wide association studies (GWAS) have identified five genetic loci associated with hippocampal volume (HV). Previous studies have described psychosocial and clinical factors (for example, smoking, type 2 diabetes and hypertension) to have an impact on HV. However, the interplay between genetic, psychosocial and clinical factors on the HV remains unclear. Still, it is likely that genetic variants and clinical or psychosocial factors jointly act in modifying HV; it might be possible they even interact. Knowledge of these factors might help to quantify ones individual risk of or rather resilience against HV loss. We investigated subjects (N=2463; 55.7% women; mean age 53 years) from the Study of Health in Pomerania (SHIP-2; SHIP-TREND-0) who underwent whole-body magnetic resonance imaging (MRI) and genotyping. HVs were estimated with FreeSurfer. For optimal nonlinear model fitting, we used regression analyses with restricted cubic splines. Genetic variants and associated psychosocial or clinical factors were jointly assessed for potential two-way interactions. We observed associations between HV and gender (P<0.0001), age (P<0.0001), body height (P<0.0001), education (P=0.0053), smoking (P=0.0058), diastolic blood pressure (P=0.0211), rs7294919 (P=0.0065), rs17178006 (P=0.0002), rs6581612 (P=0.0036), rs6741949 (P=0.0112) and rs7852872 (P=0.0451). In addition, we found three significant interactions: between rs7294919 and smoking (P=0.0473), rs7294919 and diastolic blood pressure (P=0.0447) and between rs7852872 and rs6581612 (P=0.0114). We suggest that these factors might have a role in the individual susceptibility to hippocampus-associated disorders.

Alexithymia and brain gray matter volumes in a general population sample

Alexithymia is perceived as a personality construct involving deficits in the cognitive processing of emotion. Brain areas that process emotions might be structurally altered in affected people. Subjects from the Study of Health in Pomerania who underwent whole body magnetic resonance imaging were investigated. After quality control procedures 2,589 subjects with Toronto Alexithymia Scale 20 (TAS-20) data and interview-based information on major depressive disorder (MDD) were available. After exclusion of study participants who were older than 65 years or had MDD in their lifetime, 1,685 subjects were included in the voxel-based morphometric (VBM 8) analyses. In whole-brain analyses, the TAS-20 total score was associated with less gray matter (GM) volumes of the bilateral dorsal anterior cingulate cortex (dACC). The TAS-20 factor scale difficulty identifying feelings (DIF) was associated with less GM volume in three clusters: dACC, left middle and inferior temporal gyrus, left fusiform gyrus and cerebellum. The lower GM volume in the left fusiform gyrus was specific for females. Absolute GM volume analyses also revealed associations between the factor scales difficulty describing feelings, external orientated thinking and the dACC. Adjustment for current symptoms of anxiety and depression did not change the effects sizes substantially. In conclusion, lower GM volume in the dACC represents the major structural correlate of alexithymia. Associations with DIF suggest a prominent involvement of left temporal areas. These areas represent language and semantic processing and might be involved in the cognitive processing of emotions and the conscious identification of feelings.

The impact of childhood trauma on depression: does resilience matter? Population-based results from the Study of Health in Pomerania

OBJECTIVE

Data suggests that traumatic experiences at early age contribute to the onset of major depressive disorder (MDD) in later life. This study aims at investigating the influence of dispositional resilience on this relationship.

METHODS

Two thousand and forty-six subjects aged 29-89 (SD=13.9) from a community based sample who were free of MDD during the last 12 months prior to data collection were diagnosed for Lifetime diagnosis of MDD by the Munich-Composite International Diagnostic Interview (M-CIDI) according to DSM-IV criteria. Childhood maltreatment (CM) and resilience were assessed with the Childhood Trauma Questionnaire (CTQ) and the Resilience-Scale (RS-25).

RESULTS

Both CM (OR=1.03, 95% CI [1.02, 1.04], P<.000) and resilience (OR=0.98, 95% CI [0.98, 0.99], P<.000) were associated with MDD later in life. The detrimental effects of low resilience on MDD were not only especially prominent in subjects with a history of CM (OR=3.18, 95% CI [1.84, 5.50], P<.000), but also effective in subjects without CM (OR=2.62, 95% CI [1.41, 4.88], P=.002).

CONCLUSIONS

The findings support the clinical assumption that resilient subjects may be partly protected against the detrimental long-term effects of child abuse and neglect.

An update on the interaction between the serotonin transporter promoter variant (5-HTTLPR), stress and depression, plus an exploration of non-confirming findings

In the three years since the most recent meta-analysis of the association between the serotonin transported promoter polymorphism (5-HTTLPR), stress and the development of depression, another 27 studies have been published on this issue, which is an increase of 50% more studies than were previously reviewed. In addition, previous findings of inconsistency of results across studies argued for further exploration of this relationship. From the 81 studies identified to June 2013, the significant relationship between the short form of the 5-HTTLPR was confirmed (p=.0000009), which is stronger than the relationship reported in the most recent meta-analysis in 2011. However, nearly 26% of the 81 studies reviewed failed to show any significant association between the 5-HTTLPR, stress and depression, and four studies found opposite results to those expected. Examination of the methodologies of all studies failed to indicate any flaws in the opposite or unequivocal studies, and the latter had larger sample sizes than those studies which supported the expected association, arguing that the null results were not an outcome of insufficient statistical power. The need to consider aspects of samples and measures of depression, particularly the presence of subtypes of depression in future research is discussed.

Genetic Role of BDNF Val66Met and 5-HTTLPR Polymorphisms on Depressive Disorder

OBJECTIVE

We investigated possible association between depressive disorders and BDNF Val66Met and 5-HTTLPR. Brain derived neurotrophic factor (BDNF) gene and serotonin transporter (SLC6A4) gene are promising candidate genes for depressive disorders. It has been suggested that BDNF promotes the survival and differentiation of serotonergic neurons and that serotonergic transmission exerts powerful control over BDNF gene expression.

METHODS

Final analyses were performed on 186 patients with depressive disorders and 1032 controls. Val66Met polymorphism of BDNF gene and 5-HTTLPR polymorphism of serotonin transporter gene were genotyped and allele and genotypic associations on the diagnosis of depression and age at onset of depression were analyzed.

RESULTS

The 5-HTTLPR was positively associated with depressive affected status in the total sample and in females (p=0.038 for allelewise, p=0.015 for genotype-wise associations), but, not in males. The BDNF Val66Met showed no association with depression. BDNF Val66Met and 5-HTTLPR alone were not associated with age at onset of depression. Additional analysis on the interaction between BDNF Val66Met and 5-HTTLPR found a significant association with age at onset of depression in the entire patient group. This association was also found in the female but not in the male patient group. None of the positive results survived Bonferroni correction for multiple testing.

CONCLUSION

This result suggested that BDNF Val66Met and 5-HTTLPR may contribute to depressive disorders in a complex way and that the genetic effect could differ by gender. Further studies with large number of patients will be necessary.

Gene × environment interaction studies have not properly controlled for potential confounders: the problem and the (simple) solution

Candidate gene × environment (G × E) interaction research tests the hypothesis that the effects of some environmental variable (e.g., childhood maltreatment) on some outcome measure (e.g., depression) depend on a particular genetic polymorphism. Because this research is inherently nonexperimental, investigators have been rightly concerned that detected interactions could be driven by confounders (e.g., ethnicity, gender, age, socioeconomic status) rather than by the specified genetic or environmental variables per se. In an attempt to eliminate such alternative explanations for detected G × E interactions, investigators routinely enter the potential confounders as covariates in general linear models. However, this practice does not control for the effects these variables might have on the G × E interaction. Rather, to properly control for confounders, researchers need to enter the covariate × environment and the covariate × gene interaction terms in the same model that tests the G × E term. In this manuscript, I demonstrate this point analytically and show that the practice of improperly controlling for covariates is the norm in the G × E interaction literature to date. Thus, many alternative explanations for G × E findings that investigators had thought were eliminated have not been.

Serotonin transporter availability in the midbrain and perceived social support in healthy volunteers

OBJECTIVE

Serotonin modulates human behavior and emotion. Recent evidence implies that a higher level of serotonergic activity could be associated with a higher level of perceived social support. This study aimed to examine the correlation between serotonin transporter (SERT) availability and perceived social support scores in healthy volunteers.

METHODS

111 healthy participants, 50 males and 61 females, were enrolled from the community and completed the Measurement of Support Function questionnaire. Single photon emission computed tomography (SPECT) with [(123)I] ADAM was performed to examine SERT availability.

RESULTS

Perceived social support was positively correlated with SERT availability (Spearman's ρ=0.29, p<0.01; χ(2)=7.57, p<0.01), particularly in males (Spearman's ρ=0.37, p<0 .01; χ(2)=11.77, p<0.01). Censored regressions indicated that these associations are not influenced by a ceiling effect and remained significant after controlling the effect of age.

CONCLUSIONS

This result confirmed the correlation between perceived social support and central serotonergic activity. However, this correlation was present only in males.

The association between malnutrition and psychological distress in patients with advanced head-and-neck cancer

OBJECTIVE

Malnutrition and psychological distress are often seen in patients with head-and-neck cancer, but little is known about the interrelationships between those two symptoms. The present study examined the relationship between malnutrition and psychological distress in patients with advanced head-and-neck cancer.

METHODS

Using the Patient-Generated Subjective Global Assessment, 99 patients with advanced-stage head-and-neck cancer were screened for nutrition status. The patients were also screened for psychosocial distress (using the Distress Thermometer) and for psychosocial issues (using the Problem Checklist). Any relationship between malnutrition and psychosocial distress was determined by regression and correlation analysis. We also used t-tests to compare distress levels for patients with and without specific nutrition-related symptoms.

RESULTS

The study group included 80 men and 19 women [mean age: 58.4 ± 10.9 years (range: 23-85 years)]. The correlation between poorer nutrition status and level of psychological distress was significant r = 0.37 (p < 0.001). Specifically, reduced food intake and symptoms were both positively associated with distress: r = 0.27 and r = 0.29 respectively, both significant at p < 0.01. After controlling for the effects of psychosocial problems and pain, nutrition status remained a significant predictor of distress, explaining 3.8% of the variance in the distress scores of the patients (p < 0.05).

CONCLUSIONS

Malnutrition and symptoms were strongly related to distress in patients with advanced head-and-neck cancer. Our results suggest the need for further research into the complex relationship between nutrition status and distress and into the management of both nutrition and distress in cancer care.

Associations Between Variations in TPH1 , TPH2 and SLC6A4 Genes and Postpartum Depression: A Study in the Jordanian Population

In this study, we investigated the association between tryptophan hydroxylase-1 (TPH1 ) (218A>C), tryptophan hydroxylase-2 ( TPH2 ) (1463G>A) and serotonin carrier family 6, member 4 (SLC6A4) [long (L) vs. short (S)] gene polymorphisms with post-partum depression (PPD) in women from Jordan. A total of 370 postpartum (130 depressed and 240 non depressed) women volunteered for the study. Genotyping was carried out using restriction fragment length polymorphism (RFLP) for TPH1 , amplification refractory mutation system (ARMS) for TPH2 and polymerase chain reaction (PCR) for SLC6A4 S and L. The Edinburgh postnatal depression scale was used to screen postpartum women. Both S and L alleles of SLC6A4 are common in Jordanian women (about 51.0 and 49.0%, respectively), while allele TPH1 -218C is more common (64.0%) than allele A (37.0%). Regarding TPH2 , allele A is absent from the examined women. None of the examined polymorphisms were found to be associated with PPD ( p >0.05). However, depression history, pregnancy problems and economic status were found to be significantly associated with PPD ( p <0.05). The results suggest that TPH1 , TPH2 and SLC6A4 S and L polymorphisms do not seem to be important in Jordan for predisposing to PPD.

Psychosocial state after bariatric surgery is associated with the serotonin-transporter promoter polymorphism

BACKGROUND

Bariatric surgery is the method of choice in the treatment of morbid obesity. Different genotypes of the serotonin transporter gene (5-HTT) are known to impact the prevalence of psychiatric disorders and the psychosocial state in obese individuals. In this study, we examined the influence of the 5-HTTLPR polymorphism on physiologic and psychosocial measures in morbidly obese women after bariatric surgery.

METHODS

We investigated women 1-5 years after bariatric surgery using a semi-structured interview and the Beck Depression Inventory, the Moorhead-Ardelt Quality of life questionnaire, the NEO-Five Factor Inventory and a Resilience scale. The 5-HTTLPR polymorphism (s/s, s/l, l/l) was genotyped using mouth swabs. The influence of genotype on outcome variables was analyzed by independent t test and analysis of covariance corrected for possible confounders.

RESULTS

64 women were enrolled in this study between January 2004 and September 2009. Significantly lower quality of life and higher depression, neuroticism and resilience scores were found in homozygous s-allele carriers of the 5-HTTLPR polymorphism than in l-allele carriers. Except for neuroticism, other factors (age, education, year of surgery, weight before surgery and method of surgery) did not affect the results. We found no influence of genotype on weight loss, current weight or weight before surgery.

CONCLUSION

Quality of life, mood, and resilience but not weight loss after bariatric surgery are negatively influenced by the s-allele of the 5-HTTLPR polymorphism.

The 5HTT and MAO-A polymorphisms associate with depressive mood and climacteric symptoms in postmenopausal women

OBJECTIVE

The aim of this study was to assess the influence of the 44-bp polymorphism in the 5HTTLPR (SLC 6A4) (serotonin-transporter-linked polymorphic region, solute carrier family 6 member 4) promoter region and the 30-bpVNTR (variable number of tandem repeats) polymorphism in the MAO-A (monoamine oxidase A) promoter region on the prevalence of depressive mood and the severity of climacteric symptoms in postmenopausal women.

MATERIAL AND METHODS

The study involved 630 women from northern Poland who had their last menstrual period at least one year before the study. The women did not abuse alcohol or cigarettes, had not been diagnosed as having endocrinological, cancerous or mental diseases, and had not received psychiatric treatment by the time. This survey-based study was performed using the following research instruments: the Beck Depression Inventory (BDI), to evaluate depressive symptoms, and the Blatt-Kupperman Menopausal Index, to measure the severity of climacteric symptoms.

RESULTS

The average age of the women was 57.5 ± 6.4 years. Depressive symptoms of different severity according to the BDI were diagnosed in 29.2% of the women (minor-18.6%, moderate-7.1%, severe-3.5%) and according to the Blatt-Kupperman Menopausal Index were diagnosed in 42% of the women (minor-24.1%, moderate-9.2%, severe-8.7%). Allele 'l' was significantly more common in the women without climacteric symptoms than those with minor, moderate or severe climacteric complaints (p ≤ 0.05). There was a significant correlation between the severity of climacteric and depressive symptoms (p ≤ 0.05). The women who had severe climacteric symptoms also had more severe depressive symptoms.

CONCLUSIONS

1. The 5HTTLPR gene polymorphism contributes to climacteric symptoms in postmenopausal women. 2. The Blatt-Kupperman Menopausal Index is an instrument which can not only be used for the measurement of the severity of climacteric symptoms but also the early detection of perimenopausal women at the risk of developing depressive symptoms.

A mega-analysis of genome-wide association studies for major depressive disorder

Prior genome-wide association studies (GWAS) of major depressive disorder (MDD) have met with limited success. We sought to increase statistical power to detect disease loci by conducting a GWAS mega-analysis for MDD. In the MDD discovery phase, we analyzed more than 1.2 million autosomal and X chromosome single-nucleotide polymorphisms (SNPs) in 18 759 independent and unrelated subjects of recent European ancestry (9240 MDD cases and 9519 controls). In the MDD replication phase, we evaluated 554 SNPs in independent samples (6783 MDD cases and 50 695 controls). We also conducted a cross-disorder meta-analysis using 819 autosomal SNPs with P<0.0001 for either MDD or the Psychiatric GWAS Consortium bipolar disorder (BIP) mega-analysis (9238 MDD cases/8039 controls and 6998 BIP cases/7775 controls). No SNPs achieved genome-wide significance in the MDD discovery phase, the MDD replication phase or in pre-planned secondary analyses (by sex, recurrent MDD, recurrent early-onset MDD, age of onset, pre-pubertal onset MDD or typical-like MDD from a latent class analyses of the MDD criteria). In the MDD-bipolar cross-disorder analysis, 15 SNPs exceeded genome-wide significance (P<5 × 10(-8)), and all were in a 248 kb interval of high LD on 3p21.1 (chr3:52 425 083-53 822 102, minimum P=5.9 × 10(-9) at rs2535629). Although this is the largest genome-wide analysis of MDD yet conducted, its high prevalence means that the sample is still underpowered to detect genetic effects typical for complex traits. Therefore, we were unable to identify robust and replicable findings. We discuss what this means for genetic research for MDD. The 3p21.1 MDD-BIP finding should be interpreted with caution as the most significant SNP did not replicate in MDD samples, and genotyping in independent samples will be needed to resolve its status.

Relational security moderates the effect of serotonin transporter gene polymorphism (5-HTTLPR) on stress generation and depression among adolescents

Previous research demonstrates that carriers of the short allele of the serotonin transporter gene (5-HTTLPR) show both greater susceptibility to depression in response to stressful life events and higher rates of generation of stressful events in response to depression. The current study examines relational security (i.e., self-reported beliefs about attachment security) as a moderator of these effects, building on emerging research suggesting that the short allele acts as a marker of sensitivity to the social environment. Participants were 354 Caucasian adolescents oversampled for maternal depression (137 male, 217 female), assessed at ages 15 and 20. Results indicated that the short allele predicted increased stress generation at age 20 among those with low age 15 security but decreased stress generation among those with high security, and revealed a three-way interaction between age 15 depression, age 15 security, and genotype, where depression predicted stress generation only among short allele carriers with low security. Further, among boys only, security interacted with genotype to predict longitudinal changes in depression diagnosis, with the s-allele predicting relative increases in probability of depression among boys with low security but decreases among boys with high security. Results support the notion of the short allele as a marker of social reactivity, and suggest that attachment security may buffer against the genetic vulnerability introduced by the short allele, in line with predictions of the differential susceptibility theory.

Effect of gene, environment and maternal depressive symptoms on pre-adolescence behavior problems - a longitudinal study

BACKGROUND

Depression is a common and disabling condition with a high relapse frequency. Maternal mental health problems and experience of traumatic life events are known to increase the risk of behavior problems in children. Recently, genetic factors, in particular gene-by-environment interaction models, have been implicated to explain depressive etiology. However, results are inconclusive.

METHODS

Study participants were members of the SESBiC-study. A total of 889 mothers and their children were followed during the child's age of 3 months to 12 years. Information on maternal depressive symptoms was gathered postpartum and at a 12 year follow-up. Mothers reported on child behavior and traumatic life events experienced by the child at age 12. Saliva samples were obtained from children for analysis of 5-HTTLPR and BDNF Val66Met polymorphisms.

RESULTS

Multivariate analysis showed a significant association between maternal symptoms of depression and anxiety, and internalizing problems in 12-year-old children (OR 5.72, 95% CI 3.30-9.91). Furthermore, carriers of two short alleles (s/s) of the 5-HTTLPR showed a more than 4-fold increased risk of internalizing problems at age 12 compared to l/l carriers (OR 4.73, 95% CI 2.14-10.48). No gene-by-environment interaction was found and neither depressive symptoms postpartum or traumatic experiences during childhood stayed significant in the final model.

CONCLUSIONS

Concurrent maternal symptoms of depression and anxiety are significant risk factors for behavior problems in children, which need to be taken into account in clinical practice. Furthermore, we found a main effect of 5-HTTLPR on internalizing symptoms in 12-year-old children, a finding that needs to be confirmed in future studies.

Anxiety and affective disorder comorbidity related to serotonin and other neurotransmitter systems: obsessive-compulsive disorder as an example of overlapping clinical and genetic heterogeneity

Individuals with obsessive-compulsive disorder (OCD) have also been shown to have comorbid lifetime diagnoses of major depressive disorder (MDD; rates greater than 70%), bipolar disorder (rates greater than 10%) and other anxiety disorders (e.g. panic disorder, post-traumatic stress disorder (PTSD)). In addition, overlap exists in some common genetic variants (e.g. the serotonin transporter gene (SLC6A4), the brain-derived neurotrophic factor (BDNF) gene), and rare variants in genes/chromosomal abnormalities (e.g. the 22q11 microdeletion syndrome) found across the affective/anxiety disorder spectrums. OCD has been proposed as a possible independent entity for DSM-5, but by others thought best retained as an anxiety disorder subtype (its current designation in DSM-IV), and yet by others considered best in the affective disorder spectrum. This review focuses on OCD, a well-studied but still puzzling heterogeneous disorder, regarding alterations in serotonergic, dopaminergic and glutamatergic neurotransmission in addition to other systems involved, and how related genes may be involved in the comorbidity of anxiety and affective disorders. OCD resembles disorders such as depression, in which gene × gene interactions, gene × environment interactions and stress elements coalesce to yield OC symptoms and, in some individuals, full-blown OCD with multiple comorbid disorders.