Personality traits in the first degree relatives of outpatients with depressive disorders

The effects of childhood trauma on personality in unaffected first-degree relatives of patients with major depressive disorder

ABSTRAC

OBJECTIVES: This study aimed to preliminarily and exploratorily examine the associations between childhood trauma (CT), its subtypes, and personality traits among unaffected first-degree relatives (FDR, children, or siblings) of patients with major depressive disorder (MDD).

METHODS

The study sample included three subgroups: MDD patients (N = 85), Patients' FDRs (N = 35), and healthy control individuals (HC, N = 89). The Childhood Trauma Questionnaire (CTQ) was used to assess childhood trauma and the Eysenck Personality Questionnaire was used to assess personality traits.

RESULTS

Significant differences were found in a few personality traits (p < 0.05 for extraversion, neuroticism, and psychoticism) among MDD patients, FDR, and HC, and there were no significant differences between HC and FDR. In the FDR group, compared with those without CT, participants with CT scored significantly higher for neuroticism (N) (F = 3.246, p = 0.046). CT was significantly associated with N, psychoticism (P) and Lie (L), and the strongest association was between CT total score and N. Significantly positive correlations were found between N and sexual abuse (SA) (r = 0.344, p = 0.043), emotional neglect (EN) (r = 0.394, p = 0.019), physical neglect (PN) (r = 0.393, p = 0.019), and CTQ total score (r = 0.452, p = 0.006); between P and CTQ total score (r = 0.336, p = 0.049); and significant negative correlations were found between L and EN (r = -0.446, p = 0.007), CTQ total score (r = -0.375, p = 0.027).

CONCLUSION

In unaffected FDRs, there were significant associations between childhood trauma and a few personality traits, including neuroticism, psychoticism, and lie, and emotional neglect was significantly associated with neuroticism.

Familial resemblance in mental health symptoms, social and cognitive vulnerability, and personality: A study of patients with depressive and anxiety disorders and their siblings

BACKGROUND

Investigating siblings of probands with affective disorders enables the identification of psychopathology-related risk features. Leveraging data from an older adult sample, as compared to most previous sibling studies, enabled us to study more definitive clinical profiling across the lifespan. We examined prevalence of depressive/anxiety disorders in siblings, proband-sibling resemblance in psychopathology-related features, and whether unaffected siblings showed higher levels of these features than healthy controls.

METHODS

The sample (N=929; M_age=50.6) consisted of 256 probands with lifetime depressive and/or anxiety disorders, their 380 siblings, and 293 healthy controls without affected relatives. Fifteen psychopathology-related features were investigated across four domains: mental health symptoms, social vulnerabilities, cognitive vulnerabilities, and personality.

RESULTS

Lifetime disorders were present in 50.3% of siblings. Prevalence was 2-3 times higher than Dutch population frequencies. We found small to medium probandsibling resemblance across psychopathology-related features (ρ=0.10-0.32). Unaffected siblings reported poorer interpersonal functioning and more negative life events, childhood trauma, and rumination than healthy controls.

LIMITATIONS

Due to the cross-sectional study design, the directionality of effects cannot be determined. No inferences can be made about potential differences in familial resemblance in psychopathology-related features between high- and low-risk families.

CONCLUSIONS

Siblings of probands with affective disorders are at higher risk for depressive/anxiety disorders. Even when unaffected, still show higher psychosocial vulnerability than healthy controls. Nevertheless, the only modest proband-sibling resemblance across psychopathology-related features suggests that individual mechanisms differentiate clinical trajectories across the lifespan. Identification of these mechanisms is crucial to improve resilience in subjects with familial risk.

Neural Correlates of Three Promising Endophenotypes of Depression: Evidence from the EMBARC Study

Major depressive disorder (MDD) is clinically, and likely pathophysiologically, heterogeneous. A potentially fruitful approach to parsing this heterogeneity is to focus on promising endophenotypes. Guided by the NIMH Research Domain Criteria initiative, we used source localization of scalp-recorded EEG resting data to examine the neural correlates of three emerging endophenotypes of depression: neuroticism, blunted reward learning, and cognitive control deficits. Data were drawn from the ongoing multi-site EMBARC study. We estimated intracranial current density for standard EEG frequency bands in 82 unmedicated adults with MDD, using Low-Resolution Brain Electromagnetic Tomography. Region-of-interest and whole-brain analyses tested associations between resting state EEG current density and endophenotypes of interest. Neuroticism was associated with increased resting gamma (36.5-44 Hz) current density in the ventral (subgenual) anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC). In contrast, reduced cognitive control correlated with decreased gamma activity in the left dorsolateral prefrontal cortex (dlPFC), decreased theta (6.5-8 Hz) and alpha2 (10.5-12 Hz) activity in the dorsal ACC, and increased alpha2 activity in the right dlPFC. Finally, blunted reward learning correlated with lower OFC and left dlPFC gamma activity. Computational modeling of trial-by-trial reinforcement learning further indicated that lower OFC gamma activity was linked to reduced reward sensitivity. Three putative endophenotypes of depression were found to have partially dissociable resting intracranial EEG correlates, reflecting different underlying neural dysfunctions. Overall, these findings highlight the need to parse the heterogeneity of MDD by focusing on promising endophenotypes linked to specific pathophysiological abnormalities.

A review of selected candidate endophenotypes for depression

Endophenotypes are proposed to occupy an intermediate position in the pathway between genotype and phenotype in genetically complex disorders such as depression. To be considered an endophenotype, a construct must meet a set of criteria proposed by Gottesman and Gould (2003). In this qualitative review, we summarize evidence for each criterion for several putative endophenotypes for depression: neuroticism, morning cortisol, frontal asymmetry of cortical electrical activity, reward learning, and biases of attention and memory. Our review indicates that while there is strong support for some depression endophenotypes, other putative endophenotypes lack data or have inconsistent findings for core criteria.

PPP2R2C as a candidate gene of a temperament and character trait-based endophenotype of ADHD

There are several lines of evidence that the 4p16 region is a candidate locus of both attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder. None of the harbored candidate genes of this region were hitherto shown to be associated with ADHD despite promising functionality. One of the most promising candidate genes in this region is protein phosphatase 2, regulatory subunit B, gamma (PPP2R2C), which, however, thus far has not been assessed for a potential association with ADHD. A total of 513 in- and outpatients affected with adult ADHD and 536 controls as well as 170 nuclear families with 249 children affected with ADHD were genotyped for 35 SNPs, which tagged the promoter region, the 5' and 3' UTRs, and the exons of the PPP2R2C. Two independent samples provided evidence that the major G allele of rs16838844 increases risk toward ADHD. Allelic variations of PPP2R2C rs16838698 on the other hand might be associated with a variety of personality traits. There is evidence that allelic variation in PPP2R2C may be associated with a variety of personality traits and ADHD per se. Nevertheless, as all those conditions are comorbid, PPP2R2C might reflect a common underlying neurobiological risk factor.

The profile and familiality of personality traits in mood disorder families

OBJECTIVE

Personality traits have impacts on individuals' response to stress and mood expression. The current study aimed to investigate the profile of personality traits in patients with bipolar disorders and major depressive disorder (MDD). Familial aggregation of personality traits in mood disorder families was also evaluated.

METHODS

We recruited 260 clinical patients of MDD (92), bipolar disorder-I and II (BP-I=111, BP-II=57), 190 first-degree relatives, and 180 controls. Four personality traits were assessed using the Eysenck and Tridimensional Personality Questionnaires, including Extraversion (E), Neuroticism (N), Harm Avoidance (HA), and Novelty Seeking (NS). The magnitude of familiality of personality traits in mood disorder families was evaluated by mixed models and intra-class correlation coefficients (ICC).

RESULTS

Patients with mood disorders had lower E, and higher N, HA and NS than controls. Unaffected relatives were not differed from controls in the four personality traits. BP-I had higher E, NS and lower N, HA than MDD patients (p<0.01). The scale N further distinguished BP-I from BP-II (p=0.02) with lower N among BP-I patients. There exhibited moderate familiality in E (ICC=0.184-0.239) and HA (ICC=0.355) in bipolar disorder families.

LIMITATION

Personality traits were accessed cross-sectionally without quantitatively controlled severity of mood symptoms.

CONCLUSION

Different patterns of personality traits distinguish patients from unaffected individuals as well as separate diagnoses of mood disorders, indicating the usage of more comprehensive evaluation of personality traits in clinical settings. Familiality of extraversion and harm avoidance in bipolar disorder families provides insights for further investigating correlates of comorbid behavioral problems in bipolar disorders.

Cognitive mechanisms of treatment in depression

Cognitive abnormalities are a core feature of depression, and biases toward negatively toned emotional information are common, but are they a cause or a consequence of depressive symptoms? Here, we propose a 'cognitive neuropsychological' model of depression, suggesting that negative information processing biases have a central causal role in the development of symptoms of depression, and that treatments exert their beneficial effects by abolishing these biases. We review the evidence pertaining to this model: briefly with respect to currently depressed patients, and in more detail with respect to individuals at risk for depression and the effects of antidepressant treatments. As well as being present in currently depressed individuals, negative biases are detectable in those vulnerable for depression due to neuroticism, genetic risk, or previous depressive illness. Recent evidence provides strong support for the notion that both antidepressant drugs and psychological therapies modify negative biases, providing a common mechanism for understanding treatments for depression. Intriguingly, it may even be possible to predict which patients will benefit most from which treatments on the basis of neural responses to negative stimuli. However, further research is required to ascertain whether negative processing biases will be useful in predicting, detecting, and treating depression, and hence in preventing a chronic, relapsing course of illness.

Personality and depression: explanatory models and review of the evidence

Understanding the association between personality and depression has implications for elucidating etiology and comorbidity, identifying at-risk individuals, and tailoring treatment. We discuss seven major models that have been proposed to explain the relation between personality and depression, and we review key methodological issues, including study design, the heterogeneity of mood disorders, and the assessment of personality. We then selectively review the extensive empirical literature on the role of personality traits in depression in adults and children. Current evidence suggests that depression is linked to traits such as neuroticism/negative emotionality, extraversion/positive emotionality, and conscientiousness. Moreover, personality characteristics appear to contribute to the onset and course of depression through a variety of pathways. Implications for prevention and prediction of treatment response are discussed, as well as specific considerations to guide future research on the relation between personality and depression.

Combining self-defeating and depressive personality symptoms into one construct

In the history of the DSM, two disorders have been proposed for consideration that shared much in common - self-defeating personality disorder (SDPD) and depressive personality disorder (DPD). In a previous paper, it was reported that SDPD (n = 34) and DPD (n = 240) shared a diagnostic overlap of 70%. It was concluded that SDPD could not be empirically supported as a diagnostic category. In this paper, the overlap of the two disorders was explored further in this same sample (n = 1,200) of psychiatric outpatients. We found that symptoms of the two disorders were positively correlated. Confirmatory factor analysis (CFA) provided strong support for a model with two distinct, but very highly correlated constructs. Based on the hypothesis that SDPD and DPD are separate but related, a second-order CFA factor was fit to the data to further examine the strong association between the two disorders. Taken collectively, it is concluded that DPD and SDPD are components of the same construct, and that the current DPD and SDPD diagnoses as proposed in the DSM are actually subtypes of a common personality pathology (i.e. a second-order factor).

Depressive personality disorder, dysthymia, and their relationship to perfectionism

This paper reports the results of two studies in a nonclinical (n=105) and primary care outpatient sample (n=110), in which Depressive Personality Disorder (DPD), Dysthymia, and depression were assessed for their distinctive relationship with perfectionism. Results from both studies found that self-reported DPD, Dysthymia, and depressive symptoms were all intercorrelated, and that DPD, Dysthymia, and depressive symptoms were correlated with three dimensions of perfectionism-Concern over Mistakes, Doubts about Actions, and Parental Criticism. In the nonclinical sample, variance in measures of DPD was predicted by measures of perfectionism after controlling for depression and Dysthymia symptoms. A similar pattern of findings was observed in the primary care sample. This relationship with perfectionism did not occur when Dysthymia or depressive symptoms were predicted. Nevertheless, much of the variance in measures of DPD, Dysthymia, and depressive symptoms is associated with each other and not perfectionism. It is concluded that a common factor or set of factors underlies these disorders, but that DPD may be more strongly related to perfectionism than Dysthymia and depression. As a common factor(s) is identified, measures of DPD and Dysthymia may be refined, thereby increasing the discriminant validity of their measures.

Subclinical psychopathology and socio-economic status in unaffected twins discordant for affective disorder

BACKGROUND

The most potent risk factor for affective disorders is a family history of affective disorder but the specific factors that are transmitted in families are unknown. It is possible to investigate the relation between risk factors and affective disorder by using a high-risk design e.g.: a study of the healthy relatives of patients with affective disorders.

AIM

To compare psychopathology and socio-economic status between twins with a co-twin history of affective disorder and twins without.

METHODS

In a cross-sectional high-risk case-control study, healthy monozygotic and dizygotic twins with (High-Risk twins) and without (Low-Risk twins) a co-twin history of affective disorder were identified through nation-wide registers. Participants were assessed using semi-structured psychiatric interviews and self-rating of psychopathology.

RESULTS

High-Risk twins had a lower education level, a lower work position and tendency towards being more often unemployed and early retired than the Low-Risk twins. Furthermore, they presented higher rates of subclinical affective symptoms and were more likely to experience a minor psychiatric diagnosis.

CONCLUSION

Healthy twins with a high genetic liability to affective disorder seem to present lower socio-economic status, higher rates of subclinical affective symptoms and more often experience a minor psychiatric diagnosis than twins with no familial history of affective disorder. It is not possible from the present cross-sectional data to determine the causality of these findings, thus genetic liability to affective disorder, socio-economic status and minor psychopathology seem to have a complex interrelation.

Personality: is it a viable endophenotype for genetic studies of bipolar affective disorder?

Progress in identifying the genetic basis of bipolar affective disorder has been disappointing, most probably because of the genetic and phenotypic heterogeneity of the condition. These setbacks have led to the adoption of alternative strategies such as the use of endophenotypes or intermediate traits to identify those individuals at genetic risk for developing the disorder. Gottesman and Gould [Am J Psychiatry (2003), 160:636], in a review of the endophenotypic concept, have suggested five criteria that should be characteristic of a trait in order for it to qualify as an endophenotype. These five criteria are used in order to assess the viability of using personality traits as endophenotypes for genetic analyses of bipolar disorder. A review of the literature suggests that certain personality traits or temperaments are associated with the illness in a state independent manner, that personality is at least partly heritable, and that various temperaments aggregate in the non-affected relatives of bipolar probands. Nevertheless, it is unclear whether specific personality traits co-segregate with affectively ill individuals. We conclude that personality profiling of probands and their relatives may facilitate molecular genetic work, but given the fact that personality is itself a complex trait, its use as an endophenotype has certain limitations.

Do personality traits predict first onset in depressive and bipolar disorder?

The aim was to investigate whether personality traits predict onset of the first depressive or manic episode (the vulnerability hypothesis) and whether personality might be altered by the mood disorder (the scar hypothesis). A systematic review of population-based and high-risk studies concerning personality traits and affective disorder in adults was conducted. Nine cross-sectional high-risk studies, seven longitudinal high-risk studies and nine longitudinal population-based studies were found. Most studies support the vulnerability hypothesis and there is evidence that neuroticism is a premorbid risk factor for developing depressive disorder. The evidence for the scar hypothesis is sparse, but the studies with the strongest design showed evidence for both hypotheses. Only few studies of bipolar disorder were found and the association between personality traits and bipolar disorder is unclear. Neuroticism seem to be a risk factor by which vulnerable individuals can be identified, thus preventing the development of depressive disorder. A connection between personality traits and development of bipolar disorder, and evidence of a personality-changing effect of affective episodes need to be further investigated.

Social functioning and personality of subjects at familial risk for affective disorder

BACKGROUND

Particular patterns of personality (e.g., neuroticism, obsessionality) and difficulties in various social roles have been found to be associated with unipolar depression. Interpersonal and instrumental difficulties of depressives can be understood either as a risk factor, or as a consequence caused by the disorder itself. Concerning patients with bipolar disorder, there is some evidence that their premorbid level of occupational and educational achievement is often superior when compared to the premorbid functioning of patients with unipolar depression.

METHODS

Personality features and the level of social functioning of 114 high-risk subjects (healthy first-degree relatives of patients suffering from an affective disorder) have been investigated using self- and expert-ratings. Sixty-three subjects without a personal and family history of psychiatric disorder served as the reference group.

RESULTS

Relatives of melancholic depressives described themselves as more neurotic than controls but proved to be inconspicuous regarding their role functioning. Relatives of bipolar I patients were more strongly oriented toward social norms, and their instrumental role functioning was superior to that of controls. Neuroticism was strongly associated with depressive symptoms.

LIMITATION

The statistical power of our data is sufficient to detect medium effect sizes but is insufficient for identifying small group differences.

CONCLUSION

Whether these discriminating personality features and other variables (not characterising the high-risk group (HRG) as a whole) act as true vulnerability factor have to be clarified by a follow-up investigation.

The relation between depression and anxiety: an evaluation of the tripartite, approach-withdrawal and valence-arousal models

Epidemiological studies have consistently reported that depressive and anxiety disorders co-occur frequently. This paper reviews the evidence for three models that have been proposed to explain the relation between these two conditions-the tripartite, the approach-withdrawal, and valence-arousal models. Specifically, we focus on predictions that the three models generate for cross-sectional studies, prospective and family/twin studies of personality, and EEG studies. In sum, no model was strongly supported across all types of studies, though specific aspects of each model were. Because of the heterogeneity of depression and anxiety disorders, a model with 2-4 factors or dimensions may not be sufficient to explain the relation between the two conditions.

Depressive personality in the relatives of outpatients with dysthymic disorder and episodic major depressive disorder and normal controls

BACKGROUND

This study examined whether there is a familial relationship between depressive personality and the mood disorders.

METHOD

Rates of depressive personality were compared in 161 relatives of outpatients with dysthymic disorder (DD), 75 relatives of outpatients with non-chronic major depressive disorder (MDD), and 90 relatives of normal controls. All probands and relatives were evaluated using structured diagnostic interviews for Axis I disorders and depressive personality traits.

RESULTS

The relatives of patients with DD exhibited a significantly higher rate of depressive personality than the relatives of normal controls, while the relatives of patients with MDD fell in between, and did not differ from, the other two groups. These results held after controlling for a lifetime history of mood disorder in the relatives, and could not be explained by an increased rate of depressive personality in the DD probands.

LIMITATIONS

The sample size was modest, comorbid non-mood Axis I and II disorders in the relatives were not controlled, and DSM-IV criteria for depressive personality disorder were not yet available at the time the study was undertaken.

CONCLUSION

These findings are consistent with the view that depressive personality is part of a spectrum of mood disorders with a shared familial liability, but suggest that this link is strongest with chronic forms of depression such as DD and double depression.

Personality in patients with affective disorders and their relatives

BACKGROUND

In studies of both patients and high-risk subjects, particular patterns of personality have been found to be associated with affective disorders. Neuroticism and features of the melancholic type of personality seem to be risk factors for depression while premorbid features of the manic type of personality predominate in patients with more manic than depressive episodes. While neuroticism prevails in the majority of mental disorders, the 'affective' personality variants appear to be more specifically associated with affective disorders.

METHODS

Personality features were investigated in 122 recovered patients with affective disorders, 58 first-degree relatives (high-risk subjects (HR)) and in the respective control groups (n=48; n=29). Patients were subdivided into: unipolar depression (melancholic subtype); bipolar II; bipolar I with more depressive episodes and bipolar I with more manic episodes. Personality measures were based on the Biographical Personality Interview (BPI) and the Munich Personality Test (MPT).

RESULTS

The melancholic personality type (BPI) decreased from the unipolar depressives to the mainly manic group, while features of the manic type increased. MPT scores failed to discriminate between subgroups of patients. HR were significantly more introverted and had a stronger orientation towards social norms than controls according to the MPT, and showed a tendency towards the melancholic type according to the BPI.

LIMITATIONS

The sizes of some groups or subgroups are relatively small. Therefore, they have to be enlarged in the continuation of the study so as to increase the power of the statistical tests and thus to ascertain the robustness of the results.

CONCLUSION

Features of the typus melancholicus seem to be a risk factor for depression. The identification of highly predictive risk factors provides an opportunity for the development of prevention programs.

Personality differences between patients with major depression and bipolar disorder--the impact of minor symptoms on self-ratings of personality

The study explores whether minor symptoms of patients in recovery from a mood disorder have an impact on self-ratings of personality with special consideration of potential differences between diagnostic groups. 90 recovered DSM-III-R major unipolar depressives and 167 recovered bipolars were compared with respect to scale values of the Munich Personality Test (MPT). Major depressives showed significantly higher scores on the MPT scales Rigidity and Orientation towards Social Norms, and lower scores on Extraversion than the bipolar patients. Using a LISREL-model, psychopathology was found to have a significant impact on Neuroticism and Extraversion, but not on Rigidity and on Orientation towards Social Norms. Controlling for symptomatology, the differences in the MPT scale values of the two diagnostic groups remained significant and can hardly be sufficiently explained by residual symptomatology.