Treatment Outcome-Related White Matter Differences in Veterans with Posttraumatic Stress Disorder

Abstract

Posttraumatic stress disorder (PTSD) is a debilitating disorder that has been associated with brain abnormalities, including white matter alterations. However, little is known about the effect of treatment on these brain alterations. To investigate the course of white matter alterations in PTSD, we used a longitudinal design investigating treatment effects on white matter integrity using diffusion tensor imaging (DTI). Diffusion tensor and magnetization transfer images were obtained pre-and posttreatment from veterans with (n = 39) and without PTSD (n = 22). After treatment, 16 PTSD patients were remitted, and 23 had persistent PTSD based on PTSD diagnosis. The dorsal and hippocampal cingulum bundle, stria terminalis, and fornix were investigated as regions of interest. Exploratory whole-brain analyses were also performed. Groups were compared with repeated-measures ANOVA for fractional anisotropy (FA), and magnetization transfer ratio. Persistently symptomatic PTSD patients had increasing FA of the dorsal cingulum over time, and at reassessment these FA values were higher than both combat controls and the remitted PTSD group. Group-by-time interactions for FA were found in the hippocampal cingulum, fornix, and stria terminalis, posterior corona radiata, and superior longitudinal fasciculus. Our results indicate that higher FA of the dorsal cingulum bundle may be an acquired feature of persistent PTSD that develops over time. Furthermore, treatment might have differential effects on the hippocampal cingulum, fornix, stria terminalis, posterior corona radiata, and superior longitudinal fasciculus in remitted vs persistent PTSD patients. This study contributes to a better understanding of the neural underpinnings of PTSD treatment outcome.

Decreased uncinate fasciculus tract integrity in male

“…64 However, both increased and decreased FA values were previously found at different locations of the cingulum bundle and superior longitudinal fasciculus in patients with PTSD, 18 possibly explaining why we did not find white matter alterations in the tracts we reconstructed using tractography (i.e., averaging over the entire tract, or larger segments along the tracts, compared with whole-brain voxel-wise techniques used in previous studies). Additionally, contradictory results between previous studies and our study may be explained by differences in study designs, such as the control group used (i.e., nontraumatized or trauma-exposed controls), the duration of PTSD and sex-specific effects on tract integrity.…”

The efficacy of recommended treatments for veterans with PTSD: A metaregression analysis

“…Current advances in magnetic resonance imaging (MRI) scan abilities combined with longitudinal study designs allow researchers to connect psychoneurobiological information to treatment outcome (e.g., Kennis et al, 2015). There is definitely a need to examine the neurobiological pathways of high symptomatology patients against moderate and low symptomatology patients for a better understanding of the neural underpinnings of treatment resistant veterans.…”

Synaptic Loss and the Pathophysiology of PTSD: Implications for Ketamine as a Prototype Novel Therapeutic

“…This is a relatively new area of research. Some studies suggest that psychotherapy may increase regional cortical volumes or white matter integrity (increased fractional anisotropy in diffusion weighted imaging) in PTSD, but these increases are not universally associated with clinical improvement [87•, 88, 89]. As opposed to cognitive therapies, which aim to address aberrant thought patterns, cognitive remediation therapies are a form of “brain exercise” that aims to engage experience-dependent neuroplasticity in order to restore or enhance functional connectivity [90, 91].…”