The atrophy and laterality of the hippocampal subfields in parents with or without posttraumatic stress disorder who lost their only child in China

Abstract

Investigating hippocampal subfields may provide new and important insights into the pathophysiology of posttraumatic stress disorder (PTSD). However, no study has examined the hippocampal subfield volume changes in parents with or without PTSD who had lost their only child and could no longer conceive in China. Fifty-seven parents with PTSD (PTSD+), 11 trauma-exposed parents without PTSD (PTSD-), and 39 non-traumatized controls were recruited to examine the hippocampal subfield volumes using magnetic resonance imaging. Correlations of the volumes with the time since trauma and Clinician-Administered PTSD Scale (CAPS) scores were investigated in the PTSD+ group. The volumes of the bilateral cornu ammonis (CA) 2-3, CA4-dentate gyrus (DG), and left subiculum were significantly smaller in the PTSD+ and PTSD- groups than in the controls, but there were no significant differences between the PTSD+ and PTSD- groups. Additionally, the left CA2-3 and CA4-DG volumes reduced more than those on the right side in the PTSD+ and PTSD- groups. The subfield volumes were not related to the time since trauma and the CAPS scores in the PTSD+ group. In conclusion, hippocampal subfield volumes decreased in parents who lost their only child with or without PTSD, and the volumetric reduction may be independent of PTSD and trauma-related. Moreover, the hippocampal volume deficits showed laterality that the left side was affected more than the right, and the hippocampal subfields may show differential vulnerabilities to trauma/PTSD, with the CA2-3 and CA4-DG subfields more sensitive than others.

Keywords: Bereavement; Hippocampus; Magnetic resonance imaging; Posttraumatic stress disorder; Subfield; Volume.