Relationship among Dexamethasone Suppression Test, personality disorders and stressful life events in clinical subtypes of major depression: An exploratory study

: BACKGROUND: The present study aimed to investigate the relationship between dexamethasone suppression test, personality disorder, stressful life events and depression. MATERIAL: Fifty patients (15 males and 35 females) aged 41.0 +/- 11.4 years, suffering from Major Depression according to DSM-IV criteria entered the study. METHOD: Diagnosis was obtained with the aid of the SCAN v 2.0 and the IPDE. Psychometric assessment included the HDRS, HAS, the Newcastle Scale (version 1965 and 1971), the Diagnostic Melancholia Scale, the Personality Deviance Scale and the GAF scale. The 1 mg DST was used. STATISTICAL ANALYSIS: Included MANOVA, ANOVA with LSD post hoc test and chi-square test. RESULTS: Sixteen (32%) patients were non-suppressors. Eight patients without Personality Disorder (PD) (23.5%), and 5 of those with PD of cluster B (50%) were non-suppressors. Atypical patients were the subtype with the highest rate of non-suppression (42.85%). No difference between suppressors and non-suppressors was detected in any of the scales. DISCUSSION: The results of the current study suggest that pathological DST is not a core feature of major depression. They also suggest that there are more than one subtypes of depression, concerning the response to stress. It seems that the majority of depressed patients (50%) does not experience high levels of stress either in terms of self reported experience or neuroendocrine function. The rest of patients however, either experience high levels of stress, or manifest its somatic analogue (DST non-suppression) or have a very low threshold of stress tolerance, which makes them to behave in a hostile way.     

The measurement of subjective response to stressful life events

A scale was developed to assess subjective responses to stressful life events. Over 400 subjects (divided between psychiatric patients and nonpatients) completed the 14-item response-to-stress scale for events perceived as personally important. Optimal scale item weights were assigned on the basis of Nishisato's dual scaling procedure. Four items, typically associated with responses to stress, did not contribute to the item-weight solution and were dropped from the scale. Factor analyses showed that responses to stress loaded on one bipolar factor composed of four emotional distress items and six control-management items. In contrast to previous methods developed to assess response to stress, there was less than 4% overlap between the subjective response to stress mean scores and the total number of events endorsed by each subject. Also, the correlations between simple event counts and symptom index scores were smaller than those between the subjective stress-response scores and the symptom variable. The influence of demographic factors on both the patients' and nonpatients' responses to stress were analyzed.     

Interacting effect of BDNF Val66Met polymorphism and stressful life events on adolescent depression

There is a strong etiological link between brain‐derived neurotrophic factor and depression, but the neurocellular mechanisms and gene–environment interactions remain obscure. This study investigated whether one functional polymorphism in the brain‐derived neurotrophic factor gene (BDNF Val66Met) modulates the influence of stressful life events on adolescent depressive symptoms. A total of 780 pairs of ethnic Han Chinese adolescent twins, 11–17 years of age, were randomly assigned to one of two subgroups (twin1 and twin2). All subjects were genotyped as Val/Val, Val/Met or Met/Met, and assessed for depressive symptoms using the Children's Depression Inventory. The level of environmental stress was estimated by the frequency of stressful life events using the Life Events Checklist. The frequency of stressful life events was significantly correlated with depressive symptoms (twin1: β = 0.21, P = 0.01; twin2: β = 0.27, P < 0.01), but there was no significant main effect of the BDNF Val66Met genotype on depressive symptoms. In both subgroups, however, the interaction between the BDNF Val66Met genotype and stressful life event frequency was significant (twin1: β = 0.19, P = 0.01; twin2: β = 0.15, P = 0.04); individuals with one or two Val alleles demonstrated a greater susceptibility to both the detrimental effects of higher stress and the beneficial effects of lower stress compared to the Met/Met genotype. These findings support the ‘differential‐susceptibility’ hypothesis, whereby the BDNF Val allele modulates the influence of environmental stress on depression by enhancing the neuroplastic response to all life events.     

The effect of stressful life events on EMG biofeedback and relaxation training in the treatment of anxiety

The present study evaluated the effect of frontal EMG biofeedback and relaxation training on a group of 20 anxious patients experiencing stressful life events. The patients were divided into two groups, high and low in stress, based on their life change score on the Recent Life Changes Questionnaire. Patients were evaluated at pre, post, and 6-week follow-up. Treatment consisted of 10 sessions of biofeedback-assisted relaxation. Results indicated that the high stress group showed pre to post changes on anxiety, depression, symptoms, and EMG, while low stress showed no change. Post to follow-up comparisons showed maintenance of improvement for the high stress group and no change for low stress. From pre to follow-up assessment, the high stress group showed significant changes. Both groups reported internal attributions following biofeedback and relaxation training. The high stress group attributed their improvement to the belief they were in control of their minds and bodies, while the low stress group most frequently reported the effort put into the task. The results indicate support for a cognitive explanation for some of biofeedback's effects.     

Association between genes,stressful childhood events and processing bias in depression vulnerable individuals

The brain‐derived neurotrophic factor (BDNF) and catechol‐O‐methyltransferase (COMT) genes are relevant candidates for depression. Variation in these genes is associated with stress sensitivity and depressotypic cognitive biases. The interaction between genes and stressful events is considered as an important mechanism in the development of depression. This study examined the effects of the BDNF and COMT genes on biased processing and the interaction with childhood stress in vulnerable individuals. A total of 198 remitted depressed individuals performed an n‐back task with emotional facial stimuli (happy and sad). Childhood events were measured with a questionnaire. Genotype by childhood events interactions were analyzed for happy and sad expressions for BDNF (Val66Met; rs6265) and COMT (Val158Met; rs4680), individually and combined. BDNF and COMT both interacted significantly (P = 0.006 and P = 0.014, respectively) with childhood trauma on reaction time for happy faces. For both genes, Met‐carriers with childhood trauma showed less positive bias for happy faces than those without childhood trauma. Val‐carriers did not show a differential bias. Individuals with childhood trauma and 3 or 4 risk alleles (BDNF and COMT combined) showed less positive bias than those without childhood trauma (P = 0.011). The BDNF × COMT × childhood trauma interaction yielded a P = 0.055, but had limited power. A potential weakness is the measurement method of the childhood events, as negative bias might have affected participants' recall. Our findings endorse the association of BDNF and COMT with stress and depression and provide a possible intermediate, i.e. biased processing of positive information. Tailoring treatment to specific risk profiles based on genetic susceptibility and childhood stress could be promising.     

Personal experiences of the psoriasis and its relation to the stressful life events

Psoriasis is a disease with a profound impact on the psychological and social aspects of the patient, particularly because of its visibility. Quality of life is impaired and different mental health disorders like depression, anxiety, alcoholism, posttraumatic stress disorder (PTSD) are found among persons suffering from psoriasis. Studies have shown the influence of stressful life events on onset, exacerbation and relapse of psoriasis. Rare studies explored prevalence of psoriasis during war times and relations between psoriasis and war provoked PTSD. Psoriasis is a disease with multiple possible causes and additional caution is necessary among medical professional to recognize all contributing factors. This report describes a case of a person whose first episode of psoriasis appeared six months after engaging in combat activities. He is diagnosed with psoriasis vulgaris, psoriatic arthritis and permanent personality changes after the traumatic experiences caused by war participation. His occupational history is burdened with additional causational factors; work with heavy metals and metal dusts. Cumulative effects of different aetiological factors can contribute to psoriasis with intensive trauma induced stressors serving as a trigger. His medical history indicates cognitive difficulties typical for early dementia which makes this case even more interesting. Research results suggesting common aetiology of psoriasis, autoimmune diseases and neurodegenerative diseases, indicate a need, as in the case of our patient, for multidisciplinary approach to studying aetiology of psoriasis.     

Strength gains after resistance training: the effect of stressful, negative life events

This study was designed to examine the effect of self-reported, stressful life events on strength gains after 12 weeks of resistance training. Participants were 135 undergraduates enrolled in weight training classes that met for 1.5 hours, two times per week. After a 2-week period to become familiar with weight training, participants completed the college version of the Adolescent Perceived Events Scale (APES), the Social Support Inventory, and one-repetition maximal lifts (1RM) for the bench press and squat. Maximal lifts were repeated after 12 weeks of training. Median splits for stress and social support were used to form groups. Results indicated that the low stress participants experienced a significantly greater increase in bench press and squat than their high stress counterparts. Strength gains were, however, unrelated to social support scores in either the low or high stress group. High life stress may lessen a person's ability to adapt to weight training. It may benefit coaches to monitor their athletes' stress both within and outside the training setting to maximize their recovery and adaptation.     

Association between stressful life events and exacerbation in multiple sclerosis: a meta-analysis

Objective To quantify the association between stressful life events and exacerbations of multiple sclerosis.Data sources PubMed, PsychInfo, and Psychological Abstracts searched for empirical papers from 1965 to February 2003 with terms “stress”, “trauma”, and “multiple sclerosis”.Review methods Three investigators independently reviewed papers for inclusion/exclusion criteria and extracted the relevant data, including methods, sample statistics, and outcomes.Results Of 20 studies identified, 14 were included. The meta-analysis showed a significant increase in risk of exacerbation in multiple sclerosis after stressful life events, with a weighted average effect size of d = 0.53 (95% confidence interval 0.40 to 0.65), P < 0.0001. The studies were homogenous, Q = 16.62, P = 0.22, I² = 21.8%. Neither sampling nor study methods had any effect on study outcomes.Conclusions There is a consistent association between stressful life events and subsequent exacerbation in multiple sclerosis. However these data do not allow the linking of specific stressors to exacerbations nor should they be used to infer that patients are responsible for their exacerbations. Investigation of the psychological, neuroendocrine, and immune mediators of stressful life events on exacerbation may lead to new behavioural and pharmacological strategies targeting potential links between stress and exacerbation.     

ADHD symptoms in healthy adults are associated with stressful life events and negative memory bias

Stressful life events, especially Childhood Trauma, predict ADHD symptoms. Childhood Trauma and negatively biased memory are risk factors for affective disorders. The association of life events and bias with ADHD symptoms may inform about the etiology of ADHD. Memory bias was tested using a computer task in N = 675 healthy adults. Life events and ADHD symptoms were assessed using questionnaires. The mediation of the association between life events and ADHD symptoms by memory bias was examined. We explored the roles of different types of life events and of ADHD symptom clusters. Life events and memory bias were associated with overall ADHD symptoms as well as inattention and hyperactivity/impulsivity symptom clusters. Memory bias mediated the association of Lifetime Life Events, specifically Childhood Trauma, with ADHD symptoms. Negatively biased memory may be a cognitive marker of the effects of Childhood Trauma on the development and/or persistence of ADHD symptoms.     

Inbreeding depression in benign and stressful environments

Understanding the consequences of inbreeding has important implications for a wide variety of topics in population biology. Although it is often stated in the literature that the deleterious effects of inbreeding (inbreeding depression) are expected to be more pronounced under stressful than benign conditions, this issue remains unresolved and controversial. We review the current literature on the relationship between the magnitude of inbreeding depression and environmental stress and calculate haploid lethal equivalents expressed under relatively benign and stressful conditions based on data from 34 studies. Inbreeding depression increases under stress in 76% of cases, although this increase is only significant in 48% of the studies considered. Estimates of lethal equivalents are significantly greater under stressful (mean = 1.45, median = 1.02) than relatively benign (mean = 0.85, median = 0.61) conditions. This amounts to an approximately 69% increase in inbreeding depression in a stressful vs a benign environment. However, we find strong lineage effects to be ubiquitous among studies that examine inbreeding depression in multiple environments, and a prevalence of conditionally expressed deleterious effects within lineages that are uncorrelated across environments. These results have important implications for both evolutionary and conservation biology.     

The 3111T/C polymorphism interacts with stressful life events to influence patterns of sleep in females

Genetic variations in clock-relevant genes have been investigated in relation to sleep abnormalities, both in healthy populations and in mood-disorder patients with inconsistent results. Environmental influences may moderate associations between genes and phenotype. The authors examined the CLOCK 3111T/C polymorphism and several variants within the PER3 gene and their possible interaction with stressful life events in a group of female volunteers (n = 415). Gene-environment (G × E) interactions and gene main effects were investigated on depressive symptoms using the Beck Depression Inventory and on change of sleep patterns (Item 16). Results showed a G × E interaction on alteration of sleeping pattern: the 3111C homozygous genotype reported greater disruption in sleep pattern after the experience of stressful life events. Within the PER3 gene, one G × E interaction was observed with rs228642 on sleep change. These findings show that the 3111T/C polymorphism is not associated with depressive symptoms, but only with symptoms of sleep change in the case of prior stressful life experiences. The combination of a sensitive genotype (3111C/C) and environmental stress increases vulnerability to circadian rhythm disruption in females.     

Stressful life events and depression among adolescent twin pairs

Using the twin pairs sample from the National Longitudinal Study ofAdolescent Health, we estimate bivariate Cholesky models for the influence of stressful life events (SLEs) on depressive symptoms. We show that depressive symptoms (h2Depression = .28) and dependent SLEs (events influenced by an individual's behavior) are both moderately heritable (h2SLE Dependent = .43). We find no evidence for the heritability of independent SLEs. Results from the bivariate Cholesky model suggest that roughly one-half of the correlation between depression and dependent SLEs is due to common genetic factors. Our findings suggest that attempts to characterize the causal effect of SLEs on mental health should limit their list of SLEs to those that are outside of the control of the individual.     

The relationship between stressful life events and school-related performances of type A and type B adolescents

Previous research indicates that an individual's style of coping with stress and the nature of stressful events combine to mediate responses to stress. The present study investigated the responses of Type A and Type B high school students to controllable and uncontrollable stressful life events. Specifically, the associations between life stress and gradepoint average, extracurricular activity, sports involvement, days absent, and delinquent behavior were examined. The results revealed a negative relationship between life stress and school-related performance that was more pronounced for Type B than for Type A adolescents. These findings are discussed in terms of different coping mechanisms used by Type A's and B's when encountering environmental stress.     

医学生气质性乐观与抑郁生活满意度的关系

目的 探讨医学本科生气质性乐观与抑郁体验、生活满意度的关系,为改善医学生的心理健康提供依据.方法 方便抽取某医学院校在校本科生300名,采用生活取向测量问卷(LOT)、抑郁体验问卷(DEQ)、生活满意度问卷(SWLS)进行调查.结果 男女医学生乐观水平差异无统计学意义(P＞0.05),独生子女乐观水平显著高于非独生子女,差异有统计学意义(P＜0.01);乐观维度和生活满意度显著正相关(r=0.40,P＜0.01),悲观维度与无助性抑郁和内射性抑郁维度显著正相关(r=0.39,0.49,P＜0.01);悲观因子显著正向预测抑郁(β=0.491,P＜0.01),乐观因子显著正向预测生活满意度(β=0.357,P＜0.01).结论 医学生的气质性乐观和抑郁、生活满意度有着密切关系,气质性乐观可能是影响医学生心理健康的重要因素.     

Rhythmicity in life events of an aphidophagous ladybird beetle, Cheilomenes sexmaculata

Abstract:  The present laboratory experiments have been carried out to investigate rhythms in various life events, viz. mating, oviposition, hatching, moulting, pupation and eclosion, of an aphidophagous ladybird beetle, Cheilomenes sexmaculata under laboratory conditions. Incidences of mating and eclosion occurred mostly (66% and 73% respectively) in photophase. While oviposition, hatching, moulting and pupation occurred during scotophase with the peaks of the former two distributed between time intervals 12:00–15:00 h and 21:00–00:00 h respectively. Confinement of life events that are associated with vulnerable stages in scotophase might be an adaptation to prevent their exposure to natural enemies.     

Adaptation of experimental yeast populations to stressful conditions in relation to population size

The purpose of this experiment was to find out how a population becomes adapted to extremely stressful conditions as its environment deteriorates. We created a deteriorating environment for experimental selection lines of yeast by a stepwise increase in the concentration of salt in the growth medium. After each step, we tested the ability of the lines to grow at a high concentration of salt near the lethal limit for the ancestral strain. We found that mutations enhancing growth in this highly stressful environment began to spread at intermediate salt concentrations. The degree of enhancement was related to effective population size by a power law with a small exponent. The effect size of these mutations also increased with the population size in a similar fashion. From these results, we interpret adaptation to lethal stress as an indirect response to selection for resistance to previous lower levels of stress in a deteriorating environment. This suggests that the pattern of genetic correlation between successively higher levels of stress is an important factor in facilitating evolutionary rescue.     

Association of gender with clinical expression, quality of life, disability, and depression and anxiety in patients with systemic sclerosis

Objectives

To assess the association of gender with clinical expression, health-related quality of life (HRQoL), disability, and self-reported symptoms of depression and anxiety in patients with systemic sclerosis (SSc).

Methods

SSc patients fulfilling the American College of Rheumatology and/or the Leroy and Medsger criteria were assessed for clinical symptoms, disability, HRQoL, self-reported symptoms of depression and anxiety by specific measurement scales.

Results

Overall, 381 SSc patients (62 males) were included. Mean age and disease duration at the time of evaluation were 55.9 (13.3) and 9.5 (7.8) years, respectively. One-hundred-and-forty-nine (40.4%) patients had diffuse cutaneous SSc (dcSSc). On bivariate analysis, differences were observed between males and females for clinical symptoms and self-reported symptoms of depression and anxiety, however without reaching statistical significance. Indeed, a trend was found for higher body mass index (BMI) (25.0 [4.1] vs 23.0 [4.5], p = 0.013), more frequent dcSSc, echocardiography systolic pulmonary artery pressure >35 mmHg and interstitial lung disease in males than females (54.8% vs 37.2%, p = 0.010; 24.2% vs 10.5%, p = 0.003; and 54.8% vs 41.2%, p = 0.048, respectively), whereas calcinosis and self-reported anxiety symptoms tended to be more frequent in females than males (36.0% vs 21.4%, p = 0.036, and 62.3% vs 43.5%, p = 0.006, respectively). On multivariate analysis, BMI, echocardiography PAP>35 mmHg, and anxiety were the variables most closely associated with gender.

Conclusions

In SSc patients, male gender tends to be associated with diffuse disease and female gender with calcinosis and self-reported symptoms of anxiety. Disease-associated disability and HRQoL were similar in both groups.