Department of Psychology, The University of Texas at Austin, Austin, TX, USA.
Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.
Psychol Med. 2023 Apr;53(5):1906-1913. doi: 10.1017/S0033291721003548. Epub 2021 Nov 22.
Evidence suggests a link between smaller hippocampal volume (HV) and post-traumatic stress disorder (PTSD). However, there has been little prospective research testing this question directly and it remains unclear whether smaller HV confers risk or is a consequence of traumatization and PTSD.
U.S. soldiers ( = 107) completed a battery of clinical assessments, including structural magnetic resonance imaging pre-deployment. Once deployed they completed monthly assessments of traumatic-stressors and symptoms. We hypothesized that smaller HV would potentiate the effects of traumatic stressors on PTSD symptoms in theater. Analyses evaluated whether total HV, lateral (right left) HV, or HV asymmetry (right - left) moderated the effects of stressor-exposure during deployment on PTSD symptoms.
Findings revealed no interaction between total HV and average monthly traumatic-stressors on PTSD symptoms = -0.028, = 0.681 [95% confidence interval (CI) -0.167 to 0.100]. However, in the context of greater exposure to average monthly traumatic stressors, greater right HV was associated with fewer PTSD symptoms = -0.467, = 0.023 (95% CI -0.786 to -0.013), whereas greater left HV was unexpectedly associated with greater PTSD symptoms = 0.435, = 0.024 (95% CI 0.028-0.715).
Our findings highlight the importance of considering the complex role of HV, in particular HV asymmetry, in predicting the emergence of PTSD symptoms in response to war-zone trauma.
有证据表明，海马体体积较小（HV）与创伤后应激障碍（PTSD）之间存在关联。然而，直接检验这一问题的前瞻性研究较少，目前仍不清楚较小的 HV 是增加创伤风险的因素，还是创伤和 PTSD 的结果。
美国士兵（n=107）完成了一系列临床评估，包括部署前的结构磁共振成像。一旦部署，他们每月评估创伤性应激源和症状。我们假设 HV 较小会增强战场创伤性应激源对 PTSD 症状的影响。分析评估了总 HV、侧（右-左）HV 或 HV 不对称（右-左）是否调节了部署期间应激源暴露对 PTSD 症状的影响。
研究结果未发现总 HV 与平均每月创伤性应激源与 PTSD 症状之间的交互作用（β=-0.028，p=0.681[95%置信区间（CI）-0.167 至 0.100]）。然而，在经历更多平均每月创伤性应激源的情况下，较大的右侧 HV 与较少的 PTSD 症状相关（β=-0.467，p=0.023[95%CI-0.786 至 -0.013]），而较大的左侧 HV 则与 PTSD 症状增加相关（β=0.435，p=0.024[95%CI0.028 至 0.715]）。
我们的研究结果强调了考虑 HV，特别是 HV 不对称性，在预测战区创伤后 PTSD 症状出现方面的重要性。
