Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
Teachers College, Columbia University, New York City, NY, USA.
J Affect Disord. 2019 Oct 1;257:650-657. doi: 10.1016/j.jad.2019.07.022. Epub 2019 Jul 5.
Late-life generalized anxiety disorder (GAD) is one of the most common anxiety disorders in older adults. However, its neural markers have received relatively little attention. In this study, we explored the association between worry severity and limbic-prefrontal connectivity during emotional reactivity in late-life GAD.
We recruited 16 anxious (GAD) and 20 non-anxious (HC) older adults to perform the faces/shapes emotional reactivity task during functional magnetic resonance imaging (fMRI). We investigated the functional connectivity of both the amygdala and the bed nucleus of stria terminalis (BNST) with the prefrontal cortex (PFC) using generalized psychophysiological interaction (gPPI) analysis. We tested for (1) group differences in connectivity, (2) association between worry severity and connectivity, and (3) interaction between group and worry severity and its association with connectivity.
Amygdala-PFC and BNST-PFC functional connectivity were associated with worry severity in an inverse U-shape, and was independent of depression severity, global anxiety, neuroticism, and general cognitive function.
Our limitations include slightly skewed PSWQ distributions, lack of non-anxious individuals with high worry, small sample size, and low depression comorbidity in a sample of late-life GAD that may not generalize to GAD in younger populations.
This suggests that moderate worry is associated with maximum engagement of the limbic-PFC connectivity, while severe worry is associated with failure of the limbic-PFC emotional regulation circuit. This may explain the aberrant and exaggerated responses to negative stimuli observed in participants with pathological worry.
老年期广泛性焦虑障碍（GAD）是老年人中最常见的焦虑障碍之一。然而，其神经标志物受到的关注相对较少。在这项研究中，我们探讨了老年期 GAD 患者在情绪反应过程中担忧严重程度与边缘-前额叶连接的关系。
我们招募了 16 名焦虑（GAD）和 20 名非焦虑（HC）老年人，让他们在功能磁共振成像（fMRI）期间完成面孔/形状情绪反应任务。我们使用广义心理生理相互作用（gPPI）分析研究了杏仁核和终纹床核（BNST）与前额叶皮层（PFC）的功能连接。我们测试了（1）连接的组间差异，（2）担忧严重程度与连接的关联，以及（3）组间和担忧严重程度的相互作用及其与连接的关联。
杏仁核-PFC 和 BNST-PFC 功能连接与担忧严重程度呈倒 U 型相关，且与抑郁严重程度、总体焦虑、神经质和一般认知功能无关。
我们的局限性包括 PSWQ 分布略有偏斜、缺乏高担忧的非焦虑个体、样本量小以及老年期 GAD 患者的抑郁共病率低，这可能无法推广到年轻人群中的 GAD。
这表明适度的担忧与边缘-前额叶连接的最大参与相关，而严重的担忧与边缘-前额叶情绪调节回路的失败相关。这可能解释了病理性担忧患者对负面刺激的异常和过度反应。
