Koch Saskia B J, van Ast Vanessa A, Kaldewaij Reinoud, Hashemi Mahur M, Zhang Wei, Klumpers Floris, Roelofs Karin
Donders Institute, Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, The Netherlands.
Behavioural Science Institute, Radboud University Nijmegen, Nijmegen, The Netherlands.
Neuropsychopharmacology. 2021 Jun;46(7):1283-1292. doi: 10.1038/s41386-020-00947-7. Epub 2021 Jan 21.
Early interventions to improve resilience require the identification of objective risk biomarkers for PTSD symptom development. Although altered hippocampal and amygdala volumes are consistently observed in PTSD, it remains currently unknown whether they represent a predisposing vulnerability factor for PTSD symptom development or an acquired consequence of trauma exposure and/or the disorder. We conducted a longitudinal, prospective study in 210 police recruits at high risk for trauma exposure (56 females(26.7%); mean[SD] age = 24.02[5.19]). Structural MRI scans and trauma-related symptom severity were assessed at pre-trauma baseline and at 16-month follow-up. Between assessments, police recruits were exposed to various potentially traumatic events during their police training. Police recruits reported a significant increase in police-related trauma exposure and stress-related symptoms between assessments. Smaller hippocampal left dentate gyrus (DG) volumes at baseline predicted increase in self-reported PTSD symptoms (B[SE] = -0.21[0.08], p = 0.011), stress symptoms (B[SE] = -0.16[0.07], p = 0.024) and negative affect (B[SE] = -0.21[0.07], p = 0.005) upon trauma exposure. Amount of police-related trauma exposure between assessments was positively associated with an increase in left basal amygdala nucleus volume (B[SE] = 0.11[0.05], p = 0.026). Taken together, smaller DG-volumes pre-trauma may represent a predisposing neurobiological vulnerability factor for development of trauma-related symptoms. On the other hand, amount of trauma exposure between assessments was positively associated with increased amygdala basal nucleus volume, suggesting acquired neural effects. These findings suggest that preventive interventions for PTSD aimed at improving resilience could be targeted at increasing DG-volume and potentially its functioning.
早期改善心理韧性的干预措施需要识别创伤后应激障碍（PTSD）症状发展的客观风险生物标志物。尽管在PTSD患者中始终观察到海马体和杏仁核体积的改变，但目前仍不清楚它们是PTSD症状发展的易感性因素，还是创伤暴露和/或该疾病的后天结果。我们对210名有创伤暴露高风险的警察新兵进行了一项纵向前瞻性研究（56名女性，占26.7%；平均[标准差]年龄 = 24.02[5.19]）。在创伤前基线和16个月随访时进行了结构磁共振成像扫描和创伤相关症状严重程度评估。在两次评估之间，警察新兵在警察训练期间暴露于各种潜在创伤事件。警察新兵报告说，两次评估之间与警察相关的创伤暴露和压力相关症状显著增加。基线时较小的左侧海马齿状回（DG）体积预测了创伤暴露后自我报告的PTSD症状增加（B[标准误]= -0.21[0.08]，p = 0.011）、压力症状（B[标准误]= -0.16[0.07]，p = 0.024）和消极情绪（B[标准误]= -0.21[0.07]，p = 0.005）。两次评估之间与警察相关的创伤暴露量与左侧基底杏仁核体积增加呈正相关（B[标准误]= 0.11[0.05]，p = 0.026）。综上所述，创伤前较小的DG体积可能是创伤相关症状发展的易感性神经生物学因素。另一方面，两次评估之间的创伤暴露量与杏仁核基底核体积增加呈正相关，表明存在后天神经效应。这些发现表明，旨在提高心理韧性的PTSD预防性干预措施可以针对增加DG体积及其潜在功能。
