Smaller Hippocampal Volume in Posttraumatic Stress Disorder: A Multisite ENIGMA-PGC Study: Subcortical Volumetry Results From Posttraumatic Stress Disorder Consortia

Biol Psychiatry. 2018 Feb 1;83(3):244-253. doi: 10.1016/j.biopsych.2017.09.006. Epub 2017 Sep 20.

Abstract

Background: Many studies report smaller hippocampal and amygdala volumes in posttraumatic stress disorder (PTSD), but findings have not always been consistent. Here, we present the results of a large-scale neuroimaging consortium study on PTSD conducted by the Psychiatric Genomics Consortium (PGC)-Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) PTSD Working Group.

Methods: We analyzed neuroimaging and clinical data from 1868 subjects (794 PTSD patients) contributed by 16 cohorts, representing the largest neuroimaging study of PTSD to date. We assessed the volumes of eight subcortical structures (nucleus accumbens, amygdala, caudate, hippocampus, pallidum, putamen, thalamus, and lateral ventricle). We used a standardized image-analysis and quality-control pipeline established by the ENIGMA consortium.

Results: In a meta-analysis of all samples, we found significantly smaller hippocampi in subjects with current PTSD compared with trauma-exposed control subjects (Cohen's d = -0.17, p = .00054), and smaller amygdalae (d = -0.11, p = .025), although the amygdala finding did not survive a significance level that was Bonferroni corrected for multiple subcortical region comparisons (p < .0063).

Conclusions: Our study is not subject to the biases of meta-analyses of published data, and it represents an important milestone in an ongoing collaborative effort to examine the neurobiological underpinnings of PTSD and the brain's response to trauma.

Keywords: Amygdala; Childhood trauma; Gender differences; Hippocampus; PTSD; Structural MRI.

Publication types

  • Meta-Analysis
  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Adult Survivors of Child Adverse Events / statistics & numerical data*
  • Amygdala / diagnostic imaging
  • Amygdala / pathology
  • Cohort Studies
  • Corpus Striatum / diagnostic imaging
  • Corpus Striatum / pathology
  • Female
  • Hippocampus / diagnostic imaging
  • Hippocampus / pathology*
  • Humans
  • Lateral Ventricles / diagnostic imaging
  • Lateral Ventricles / pathology
  • Magnetic Resonance Imaging / statistics & numerical data
  • Male
  • Meta-Analysis as Topic
  • Neuroimaging / statistics & numerical data*
  • Sex Characteristics*
  • Stress Disorders, Post-Traumatic / diagnostic imaging
  • Stress Disorders, Post-Traumatic / pathology*
  • Thalamus / diagnostic imaging
  • Thalamus / pathology