Hadlandsmyth Katherine, Vowles Kevin E
Bath and Wiltshire Adult Chronic Fatigue Syndrome Service, Royal National Hospital for Rheumatic Diseases, Bath, UK.
J Psychosom Res. 2009 Jan;66(1):31-5. doi: 10.1016/j.jpsychores.2008.08.002. Epub 2008 Nov 22.
Chronic fatigue syndrome (CFS) is often associated with significant levels of disability. Although fatigue and depression have been found to be independently related to severity of disability, it is not clear how these three factors are mutually related. The present study sought to address this issue by specifically testing a model of mediation whereby depression was hypothesized to influence relations between fatigue and disability.
Participants included 90 individuals seeking treatment for CFS at a tertiary care facility. Each provided demographic information and completed standardized measures of depression and fatigue severity, as well as a measure of disability, which assessed difficulties in physical, psychosocial, and independence domains.
Analyses indicated that depression and fatigue were positively correlated with one another, as well as all three disability domains. Analyses of mediation indicated that depression completely mediated the relation between fatigue and psychosocial disability and partially mediated the relation between fatigue and the other two disability domains. Indirect effects tests indicated that the inclusion of depression in the statistical models was statistically meaningful.
These results replicate previous findings that fatigue and depression are independently related to disability in those with CFS. A more complex statistical model, however, suggested that depression severity substantially influenced the strength of the relation between fatigue and disability levels across a range of domains, including complete mediation in areas involving psychosocial functioning. These results may aid in clarifying contemporary conceptualizations of CFS and provide guidance in the identification of appropriate treatment targets.
慢性疲劳综合征（CFS）常伴有严重的功能障碍。尽管已发现疲劳和抑郁分别与功能障碍的严重程度相关，但尚不清楚这三个因素之间是如何相互关联的。本研究旨在通过专门测试一种中介模型来解决这一问题，该模型假设抑郁会影响疲劳与功能障碍之间的关系。
参与者包括90名在三级医疗机构寻求CFS治疗的个体。每个人都提供了人口统计学信息，并完成了抑郁和疲劳严重程度的标准化测量，以及一项功能障碍测量，该测量评估了身体、心理社会和独立领域的困难。
分析表明，抑郁与疲劳之间以及与所有三个功能障碍领域均呈正相关。中介分析表明，抑郁完全中介了疲劳与心理社会功能障碍之间的关系，并部分中介了疲劳与其他两个功能障碍领域之间的关系。间接效应检验表明，在统计模型中纳入抑郁具有统计学意义。
这些结果重复了先前的发现，即疲劳和抑郁分别与CFS患者的功能障碍相关。然而，一个更复杂的统计模型表明，抑郁严重程度在很大程度上影响了一系列领域中疲劳与功能障碍水平之间关系的强度，包括在涉及心理社会功能的领域中完全中介。这些结果可能有助于阐明CFS的当代概念，并为确定合适的治疗靶点提供指导。
