[Show abstract][Hide abstract] ABSTRACT: Recent studies examining the interaction between the 5-HTTLPR locus in the serotonin transporter gene and life stress in predicting depression have yielded equivocal results, leading some researchers to question whether 5-HTTLPR variation indeed regulates depressive responses to stress. Two possible sources of inconsistent data in this literature are imprecise stress assessment methodologies and a restricted focus on depression phenotypes as the outcome of interest, as opposed to transdiagnostic emotional symptoms such as internalizing and externalizing dimensions. The present study aimed to address these critical limitations in prior research by examining how 5-HTTLPR acts in concert with idiographically assessed daily life stress to predict transdiagnostic emotional outcomes.
One hundred and four healthy young adults genotyped for 5-HTTLPR reported on their life stress exposure and internalizing and externalizing experiences for 14 consecutive days. As hypothesized, daily stress levels were associated with severity of internalizing symptoms, but only for 5-HTTLPR S allele carriers. Additional analyses revealed that these interactive effects of 5-HTTLPR and daily life stress on internalizing symptoms extended to both the distress and fear subdomains of internalizing symptoms.
Considered together, these results support the validity of the 5-HTTLPR stress sensitivity hypothesis and suggest for the first time that variation at 5-HTTLPR moderates the effects of daily life stress on broadband symptom profiles.
Biology of mood & anxiety disorders. 01/2014; 4(1):2.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Numerous studies have supported an association between maternal depression and child psychiatric outcomes, but few have controlled for the confounding effects of both maternal and offspring co-morbidity. Thus, it remains unclear whether the correspondence between maternal and offspring depressive and anxiety disorders is better explained by associations between shared features of maternal and offspring internalizing disorders or by specific effects exerted by unique aspects of individual disorders. Method Pairs of mothers and offspring overselected for maternal depression (n = 815) were assessed at offspring age 15 years for anxiety and depressive disorders; 705 completed a follow-up at offspring age 20 years. For both mothers and offspring, structural equation modeling was used to distinguish transdiagnostic internalizing pathology - representing the overlap among all depressive and anxiety disorders - from diagnosis-specific forms of pathology. To discriminate between general versus specific pathways of intergenerational transmission of psychopathology, we examined (a) the general association between the maternal and offspring internalizing factors and (b) the correlations between maternal and offspring diagnosis-specific pathology for each disorder. RESULTS: For mothers and offspring, a unidimensional latent variable model provided the best fit to the correlations among depressive and anxiety disorders. The maternal transdiagnostic internalizing factor strongly predicted the corresponding factor among offspring. In addition, the unique component of post-traumatic stress disorder among offspring was significantly related to the analogous unique component among mothers, but specific components of other maternal disorders, including depression, did not predict corresponding offspring pathology. CONCLUSIONS: Results suggest that intergenerational transmission of internalizing disorders is largely non-specific.
Psychological Medicine 05/2013; · 5.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: With the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) scheduled for publication in 2013, researchers continue to debate the optimal classification of borderline personality disorder (BPD). Much of the discussion has focused on the relative merits of dimensional versus categorical classification schemes for BPD. Advances in statistical technologies have made it possible to adjudicate between continuous and categorical models of BPD using quantitative methods, yet no prior studies have attempted such a comparison. The current study directly compares the fit of dimensional, categorical, and hybrid models of BPD in a large community sample (N = 700) of young adults at risk for psychopathology due to elevated rates of maternal depression. BPD symptoms were assessed using the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II). Latent class, latent trait, and factor mixture models of SCID-II symptoms were estimated, and a latent trait model provided superior fit to the data, supporting a dimensional conceptualization of borderline pathology. The nosological implications of these results are discussed with respect to a "hybrid" model of BPD diagnosis currently under consideration for DSM-5.
Journal of personality disorders 10/2012; 26(5):793-803. · 3.08 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective: Peer socialization may be an important contributor to the rising prevalence of diet and muscle gain behaviors (i.e., body change behaviors) in adolescence. The present study longitudinally examined body change behaviors in preadolescents' friendship groups as predictors of preadolescents' own body change behaviors. It was predicted that peer socialization effects would vary according to the gender composition of preadolescents' friendship group. Method: Participants (N = 648, 48.8% female) were in grades 6 through 8 at Time 1 and reported their dieting and muscle-gaining behavior at three time points approximately 1 year apart. Friendship groups were identified from preadolescents' friendship nominations. Body mass index and pubertal timing were included in analyses as control variables. A multiple group latent growth curve model was used to examine hypotheses. Results: Socialization of body change behaviors in preadolescent friendship groups was observed only under certain conditions. For members of all-male friendship groups, preadolescents' dieting trajectories were predicted from friends' average level of dieting. Conclusion: Peer socialization effects are associated with trajectories of preadolescents' body change behaviors, particularly among all-male groups. Future research would benefit from incorporating the friendship group context into the study of health risk behaviors in preadolescents. (PsycINFO Database Record (c) 2012 APA, all rights reserved).
[Show abstract][Hide abstract] ABSTRACT: Originally formulated to understand the recurrence of depressive disorders, the stress generation hypothesis has recently been applied in research on anxiety and externalizing disorders. Results from these investigations, in combination with findings of extensive comorbidity between depression and other mental disorders, suggest the need for an expansion of stress generation models to include the stress generating effects of transdiagnostic pathology as well as those of specific syndromes. Employing latent variable modeling techniques to parse the general and specific elements of commonly co-occurring Axis I syndromes, the current study examined the associations of transdiagnostic internalizing and externalizing dimensions with stressful life events over time. Analyses revealed that, after adjusting for the covariation between the dimensions, internalizing was a significant predictor of interpersonal dependent stress, whereas externalizing was a significant predictor of noninterpersonal dependent stress. Neither latent dimension was associated with the occurrence of independent, or fateful, stressful life events. At the syndrome level, once variance due to the internalizing factor was partialed out, unipolar depression contributed incrementally to the generation of interpersonal dependent stress. In contrast, the presence of panic disorder produced a "stress inhibition" effect, predicting reduced exposure to interpersonal dependent stress. Additionally, dysthymia was associated with an excess of noninterpersonal dependent stress. The latent variable modeling framework used here is discussed in terms of its potential as an integrative model for stress generation research.
Journal of Abnormal Psychology 03/2012; 121(3):754-66. · 4.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Despite consistent evidence that serotonin functioning affects stress reactivity and vulnerability to aggression, research on serotonin gene-stress interactions (G × E) in the development of aggression remains limited. The present study investigated variation in the promoter region of the serotonin transporter gene (5-HTTLPR) as a moderator of the stress-aggression association at the transition to adulthood. Multiple informants and multiple measures were used to assess aggression in a cohort of 381 Australian youth (61% female, 93% Caucasian) interviewed at ages 15 and 20. At age 20, semistructured interviews assessed acute and chronic stressors occurring in the past 12 months. Structural equation modeling analyses revealed a significant main effect of chronic stress, but not 5-HTTLPR or acute stress, on increases in aggression at age 20. Consistent with G × E hypotheses, 5-HTTLPR short allele carriers demonstrated greater increments in aggression following chronic stress relative to long allele homozygotes. The strength of chronic stress G × E did not vary according to sex. Variation at 5-HTTLPR appears to contribute to individual differences in aggressive reactions to chronic stress at the transition to adulthood.
[Show abstract][Hide abstract] ABSTRACT: Tests of interpersonal theories of depression have established that elevated depression levels among peers portend increases in individuals' own depressive symptoms, a phenomenon known as depression socialization. Susceptibility to this socialization effect may be enhanced during the transition to adolescence as the strength of peer influence rises dramatically. Socialization of depressive symptoms among members of child and adolescent friendship groups was examined over a 1-year period among 648 youth in grades six through eight. Sociometric methods were utilized to identify friendship groups and ascertain the prospective effect of group-level depressive symptoms on youths' own depressive symptoms. Hierarchical linear modeling results revealed a significant socialization effect and indicated that this effect was most potent for (a) girls and (b) individuals on the periphery of friendship groups. Future studies would benefit from incorporating child and adolescent peer groups as a developmentally salient context for interpersonal models of depression.
Journal of Abnormal Psychology 08/2011; 120(4):857-67. · 4.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Building on interpersonal theories of depression, the current study sought to explore whether early childhood social withdrawal serves as a risk factor for depressive symptoms and diagnoses in young adulthood. The researchers hypothesized that social impairment at age 15 would mediate the association between social withdrawal at age 5 and depression by age 20. This mediational model was tested in a community sample of 702 Australian youth followed from mother's pregnancy to youth age 20. Structural equation modeling analyses found support for a model in which childhood social withdrawal predicted adolescent social impairment, which, in turn, predicted depression in young adulthood. Additionally, gender was found to moderate the relationship between adolescent social impairment and depression in early adulthood, with females exhibiting a stronger association between social functioning and depression at the symptom and diagnostic level. This study illuminates one potential pathway from early developing social difficulties to later depressive symptoms and disorders.
[Show abstract][Hide abstract] ABSTRACT: Variation in the promoter region of the serotonin transporter gene (5-HTTLPR) has been linked to various cognitive-affective
indices of stress sensitivity hypothesized to underlie vulnerability to depression. The current study examined the association
of 5-HTTLPR with appraisals of naturally occurring acute life stressors in a community sample of 384 youth at elevated risk
for depression due to oversampling for maternal depression. Interview measures administered at youth age 20 were used to assess
subjective and objective (assigned by an independent rating team) appraisals of the negative impact of recent acute stressful
life events. The presence of at least one S allele was associated with elevated subjective appraisals of the negative impact
of acute stressors (P=0.03). Consistent with an endophenotype perspective, support was found for a 5-HTTLPR-stress appraisals-depression mediation
model both concurrently and longitudinally. Results indicate that enhanced stress sensitivity may act as an intermediate phenotype
through which 5-HTTLPR affects risk for depression.
KeywordsDepression–Stress–Serotonin transporter gene–Endophenotype
Cognitive Therapy and Research 01/2011; · 1.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Investigations of gene-environment interaction (GxE) in depression have implicated a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) as a moderator of the stress-depression relationship. However, recent evidence for 5-HTTLPR GxE in depression has been inconsistent. This study examined the moderating effect of the val158met polymorphism in the catechol-O-methyltransferase (COMT) gene on the strength of 5-HTTLPR GxE.
A community sample of youth (n=384) was genotyped for 5-HTTLPR and COMT. A multi-method, multi-informant index of chronic family stress was derived from interviews and questionnaires administered at youth age 15. GxGxE was examined in relation to depression diagnoses between ages 15 and 20 and depressive symptoms at age 20.
Significant three-way interactions were observed for both depressive symptoms and diagnoses, such that 5-HTTLPR GxE occurred only in the context of COMT val158 allele homozygosity. For val158 homozygotes, the 5-HTTLPR LL genotype exerted a protective effect in the face of stress. No genetic main effect or two-way GxE was found for 5-HTTLPR.
Inconsistent 5-HTTLPR GxE findings to date may be partly attributable to unmeasured epistatic effects between 5-HTTLPR and COMT val158met. Identifying the conditions under which 5-HTTLPR GxE is most likely to operate may allow depression prevention and treatment efforts to target youth at highest risk.
Depression and Anxiety 08/2010; 27(8):737-45. · 4.61 Impact Factor