An Integrated Chronobiological-Cognitive Approach to Seasonal Affective Disorder

描述(由申请人提供)：拟议的NRSA项目将是一项研究培训计划的一部分，该计划将为P.I.作为精神健康的时间生物学和心理机制的临床调查员的职业生涯做准备。这项NRSA项目将是第一次整合领先的时间生物学和认知行为SAD研究人员的理论和专业知识，以测试季节性情感障碍(SAD)的综合模型。这项研究将使用前瞻性的纵向设计，通过(1)比较夏季和冬季SAD患者和从未抑郁的匹配对照组之间的易感性，以及(2)测试时间生物学和认知脆弱性在预测患者和对照组冬季抑郁严重程度方面的相对和联合贡献，在罗翰的SAD综合认知-行为模型测试中阐明SAD的病因学基础。为认知脆弱性选择的衡量标准是对非季节性抑郁症认知脆弱性的既定衡量标准，已有研究支持它们与SAD的相关性：沉思沉思；认知反应性，以及罗翰模型中提出的SAD特有季节性认知的衡量标准。时间生物学的脆弱性将通过相位角差(PAD)的季节性变化来衡量：每个参与者的昼夜节律阶段(如暗淡的褪黑素开始)和平均睡眠中点(如手腕活动记录仪所记录的)之间的时间差异。为了测试组间效应和对冬季抑郁严重程度的纵向预测，根据DSM-IV-TR标准，所有测量将在SAD患者相对没有症状的夏季完成一次，并在SAD患者经历严重抑郁发作的冬季完成一次。在纵向线性混合模型分析中，夏季认知测量和PAD的季节性变化将被用作冬季抑郁严重程度的统计预测因子。为了控制基线抑郁严重程度，将在夏季和冬季实验室访问时获得抑郁严重程度测量，夏季测量将作为控制变量进入分析。这些认知和时间生物学预测指标将被检验对冬季抑郁严重程度的独特和交互影响。作为SAD研究的领先学科的合作，这项研究代表了SAD复发的综合病因模型的第一个测试。综合病因学模型对SAD的治疗具有临床意义。具体而言，结果可能会告知是否有必要制定新的治疗策略，即针对这些脆弱性开发新的干预策略和/或利用治疗等级，以减少每年的SAD复发。

DESCRIPTION (provided by applicant): The proposed NRSA project will be part of a research training plan to prepare the P.I. for a career as a clinical investigator of the chronobiological and psychological mechanisms of mental health. This NRSA project will be the first study to integrate theory and expertise from leading chronobiological and cognitive-behavioral SAD researchers to test an integrative model of seasonal affective disorder (SAD). This study will use a prospective, longitudinal design to clarify the etiological underpinnings of SAD in a test of Rohan's integrative cognitive-behavioral model of SAD by (1) comparing the vulnerabilities between SAD patients and never-depressed matched controls at summer and winter, and (2) testing the relative and combined contributions of the chronobiological and cognitive vulnerabilities in predicting winter depression severity in patients and controls. The measures selected for the cognitive vulnerability are established measures of cognitive vulnerability to Nonseasonal depression that have research to support their relevance to SAD: brooding rumination; cognitive reactivity, and a measure of the SAD- specific seasonal cognitions proposed in Rohan's model. The chronobiological vulnerability will be measured as seasonal change in Phase Angle Difference (PAD): the difference in timing between circadian phase (as marked by the Dim Light Melatonin Onset) and the averaged midpoint of sleep (as recorded by wrist actigraphy) for each participant. To test between-group effects and the longitudinal prediction of winter depression severity, all measures will be completed once in the summer when the SAD patients are relatively asymptomatic, and once in the winter when the SAD patients are experiencing a Major depressive Episode, per DSM-IV-TR criteria. The summer cognitive measures and a seasonal change in PAD will be utilized as statistical predictors of winter depression severity in a longitudinal linear mixed model analysis. To control for baseline depression severity, depression severity measures will be obtained at both the summer and winter laboratory visits, with the summer measure will be entered into the analysis as a control variable. These cognitive and chronobiological predictors will be examined for unique and interactive effects on winter depression severity. As a collaboration of the leading disciplines in SAD research, this study represents the first test of an integrative etiological model of SAD recurrence. An integrative etiological model holds clinical implications for the treatment of SAD. Specifically results may inform whether new treatment strategies, i.e. the development of novel intervention strategies targeting these vulnerabilities and/or utilization of a treatment hierarchy, are warranted to reduce annual SAD recurrence.