Structural Connectome Disruptions in Military Personnel with Mild Traumatic Brain Injury and Post-Traumatic Stress Disorder.
Mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) are common in military populations and share numerous symptoms. Functional graph theory studies demonstrate altered small-world brain networks in mTBI and PTSD, but little is known about structural covariance networks or the potentially distinct topology of mTBI-PTSD comorbidity. The purpose of this study was to compare brain structural covariance networks in healthy active duty military service members (CON) to those with PTSD, mTBI, and mTBI-PTSD. Seventy-six service members (31 CON, 14 PTSD, 12 mTBI, 19 mTBI-PTSD) completed clinical questionnaires and structural magnetic resonance imaging scans. Cortical thickness-derived adjacency matrices were used to determine structural covariance network topologies. Pairwise comparisons for characteristic path length, clustering coefficient, modularity (global), closeness centrality (nodal), and local efficiency were made across a range of network densities (5-35%) using non-parametric permutation tests. All clinical groups showed greater levels of arousal, stress, anxiety, and depression compared with CON. Global network analysis revealed greater clustering and local efficiency in PTSD compared with CON, whereas nodal analysis indicated altered path lengths and closeness centrality in fronto-limbic areas with mTBI-PTSD. Global and nodal graph outcomes suggest distinct pathophysiological manifestations of mTBI, PTSD, and mTBI-PTSD in structural brain networks. Greater network segregation and nodal differences in fronto-limbic areas may be tied to emotional fluctuations.
['Proessl|Felix|F|', 'Dretsch|Michael N|MN|', 'Connaboy|Chris|C|', 'Lovalekar|Mita|M|', 'Dunn-Lewis|Courtenay|C|', 'Canino|Maria C|MC|', 'Sterczala|Adam J|AJ|', 'Deshpande|Gopikrishna|G|', 'Katz|Jeffrey S|JS|', 'Denney|Thomas S|TS|', 'Flanagan|Shawn D|SD|']
D000328:Adult D001924:Brain Concussion D016022:Case-Control Studies D063132:Connectome D003430:Cross-Sectional Studies D005260:Female D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008889:Military Personnel D013313:Stress Disorders, Post-Traumatic D011795:Surveys and Questionnaires D014481:United States
mTBI PTSD graph theory covariance network military service members