Gallipoli Medical Research Foundation, Greenslopes Private Hospital, Greenslopes, 4120, Australia.
Faculty of Health and Behavioural Sciences, The University of Queensland, Saint Lucia, 4067, Australia.
Mil Med Res. 2022 Sep 16;9(1):50. doi: 10.1186/s40779-022-00413-z.
Posttraumatic stress disorder (PTSD) has been associated with volumetric and white matter microstructural changes among general and veteran populations. However, regions implicated have greatly varied and often conflict between studies, potentially due to confounding comorbidities within samples. This study compared grey matter volume and white matter microstructure among Australian combat veterans with and without a lifetime diagnosis of PTSD, in a homogenous sample assessed for known confounding comorbidities.
Sixty-eight male trauma-exposed veterans (16 PTSD-diagnosed; mean age 69 years) completed a battery of psychometric assessments and underwent magnetic resonance and diffusion tensor imaging. Analyses included tract-based spatial statistics, voxel-wise analyses, diffusion connectome-based group-wise analysis, and volumetric analysis.
Significantly smaller grey matter volumes were observed in the left prefrontal cortex (P = 0.026), bilateral middle frontal gyrus (P = 0.021), and left anterior insula (P = 0.048) in the PTSD group compared to controls. Significant negative correlations were found between PTSD symptom severity and fractional anisotropy values in the left corticospinal tract (R = 0.34, P = 0.024) and left inferior cerebellar peduncle (R = 0.62, P = 0.016). No connectome-based differences in white matter properties were observed.
Findings from this study reinforce reports of white matter alterations, as indicated by reduced fractional anisotropy values, in relation to PTSD symptom severity, as well as patterns of reduced volume in the prefrontal cortex. These results contribute to the developing profile of neuroanatomical differences uniquely attributable to veterans who suffer from chronic PTSD.
创伤后应激障碍（PTSD）与一般人群和退伍军人的体积和白质微观结构变化有关。然而，所涉及的区域在很大程度上有所不同，并且在研究之间经常存在冲突，这可能是由于样本中的混杂共病。本研究比较了澳大利亚战斗退伍军人中有无终生 PTSD 诊断的灰质体积和白质微观结构，这些退伍军人在一个经过评估已知混杂共病的同质样本中。
68 名创伤后暴露的男性退伍军人（16 名 PTSD 诊断；平均年龄 69 岁）完成了一系列心理评估，并接受了磁共振和弥散张量成像。分析包括基于束流的空间统计学、体素分析、基于弥散连接组的组间分析和体积分析。
与对照组相比，PTSD 组的左侧前额叶皮质（P=0.026）、双侧额中回（P=0.021）和左侧前岛叶（P=0.048）的灰质体积明显较小。PTSD 症状严重程度与左侧皮质脊髓束（R=0.34，P=0.024）和左侧小脑下脚（R=0.62，P=0.016）的各向异性分数值呈显著负相关。未观察到基于连接组的白质特性差异。
本研究的结果加强了与 PTSD 症状严重程度相关的白质改变的报告，表现为各向异性分数值降低，以及前额叶皮质体积减少的模式。这些结果为患有慢性 PTSD 的退伍军人特有的神经解剖差异的发展特征做出了贡献。
