Personality Development and Vulnerability to First-Episode Depression

描述(申请人提供)：重度抑郁障碍(MDD)是一种常见病，常有慢性或反复发作的病程。预防被认为是减轻这种疾病负担的关键。然而，有效的预防计划需要对诱因及其传递风险的机制有透彻的了解。个性特征是MDD发病的有力预测因素，但目前还不清楚哪些特征是易受攻击的最佳标志。此外，这些联系背后的机制也没有得到很好的理解。本项目旨在确定抑郁症发病的主要人格危险因素，并阐明相关的病因过程，包括与生活压力的相互作用以及神经和内分泌机制。另一个目标是了解伴发的抑郁在多大程度上扭曲了人格测量的分数，从而为基础人格研究和临床评估提供信息。我们建议招募575名14岁和15岁的女性(偶发抑郁症风险最高的人口统计阶层)，她们从未经历过严重的抑郁症发作。参与者将接受三次亲自评估：基线评估、第18个月评估和第36个月评估。他们将完成一次彻底的诊断性访谈，一系列人格量表，以及负面生活事件、日常功能、皮质醇水平和大脑活动的测量。他们还将在评估之间进行简短的电话采访，以最大限度地减少回忆抑郁事件和压力生活事件的偏见。家庭精神病史和告密者的个性评级将从父母那里获得。我们将使用结构方程模型(SEM)来高精度地估计特征分数，并使用增长模型来消除伴随着抑郁而导致的这些评级中的扭曲。我们预计这些分析策略将大大增强我们分析的能力，并将在未来的研究中开发出纠正个性分数的公式。接下来，我们将研究个性和环境之间在MDD易损性发展中的动态相互作用。我们还将测试病理发育轨迹的两个有前景的生物标记物。此外，我们将开发一种个性筛查，在青少年经历抑郁症之前很早就识别出他们处于危险之中。这一多学科项目将形成一个研究计划的基础，该计划最终寻求设计并针对青少年抑郁症的新的预防干预措施。

DESCRIPTION (provided by applicant): Major depressive disorder (MDD) is a common illness that often has chronic or recurring course. Prevention is believed to be the key to reducing the burden of this disorder. However, an effective prevention program requires thorough knowledge of predisposing factors and mechanisms by which they convey risk. Personality characteristics are powerful predictors of MDD onset, but it is not yet clear which traits are the best markers of vulnerability. Also, the mechanisms underlying these links are not well understood. This project aims to identify main personality risk factors for depression onset and elucidate relevant etiologic processes, including interactions with life stress as well as neural and endocrinal mechanisms. Another objective is to learn how much concomitant depression distorts scores on personality measures, thus informing basic personality research and clinical assessment. We propose to recruit 575 14- and 15-year-old females (demographic stratum at highest risk for incident depression) who have never experienced a major depressive episode. Participants will be assessed in person three times: at baseline, month 18, and month 36. They will complete a thorough diagnostic interview, a battery of personality scales, as well as measures of negative life events, daily functioning, cortisol levels, and brain activity. They also will participate in brief phone interviews between assessments to minimize biases in recall of depressive episodes and stressful life events. Family psychiatric history and informant-ratings of personality will be obtained from a parent. We will use Structural Equation Modeling (SEM) to estimate trait scores with high precision, and growth modeling to remove distortions in these ratings induced by concomitant depression. We expect these analytic strategies to substantially enhance power of our analyses and will develop formulas for correcting personality scores in future studies. Next, we will examine the dynamic interplay between personality and environment in development of vulnerability to MDD. We also will test two promising biomarkers of pathological developmental trajectories. Furthermore, we will develop a personality screen to identify adolescents at risk well before they experienced depression. This multidisciplinary project will form the basis for a program of research that ultimately seeks to design and target new preventive interventions for adolescent depression.