Volumetric Differences of Thalamic Nuclei are Associated with Post-Trauma Psychopathology.

BACKGROUND: Previous investigations of whole thalamus and thalamic nuclei volumes in post-trauma psychopathology have been sparse, limited in scope, and yielded inconsistent results. To address this, volumetric estimates of whole thalamus and thalamic nuclei were obtained from structural brain MRI scans from 2,058 participants across 20 worldwide sites in the ENIGMA PTSD working group. METHODS: Thalamic volumes were compared between trauma-exposed participants with posttraumatic stress disorder (PTSD) (n=238), major depressive disorder (MDD) (n=184), comorbid PTSD+MDD (n=618), and trauma-exposed control participants (n=1,018). PTSD and MDD symptom severity, PTSD symptom clusters, and childhood trauma were similarly examined for associations with thalamic volume. RESULTS: Participants with PTSD had smaller sensorimotor thalamic nuclei, while those with MDD or comorbid PTSD+MDD had smaller mediodorsal (MD) thalamus volumes relative to controls. Severity of PTSD and MDD symptoms negatively correlated with MD volume. A significant interaction between PTSD and MDD severity was found, such that MDD severity was positively associated with whole thalamus volume only among individuals with high PTSD severity. We observed both positive and negative volumetric associations for specific PTSD symptom clusters and childhood trauma subtypes. CONCLUSIONS: Whole thalamus volume and volumes of the sensorimotor and limbic thalamus may play an important role in the development of PTSD and MDD in the aftermath of trauma exposure. The interaction between PTSD and MDD symptoms and contrasting effects across PTSD symptom clusters and types of childhood adversity suggests multiple neurobiological mechanisms are involved in shaping thalamic volume post-trauma.

Duke Scholars

Author Rajendra A. Morey Psychiatry, Child & Family Mental Health & Community Psychia ...