The environment contributes more than genetics to smaller hippocampal volume in Posttraumatic Stress Disorder (PTSD).

摘要: BACKGROUND Studies using structural magnetic resonance imaging (MRI) volumetrics showed smaller hippocampal volume in patients with post-traumatic stress disorder (PTSD). These studies were cross-sectional and did not address whether is secondary to stress-induced damage, or pre-existing factors account for the findings. The purpose of this study was use a co-twin case control design assess relative contribution genetic environmental PTSD. METHODS Monozygotic (N = 13 pairs) dizygotic (N = 21 twins history Vietnam Era military service, where one brother went developed PTSD, while his go develop underwent MR brain. Structural MRI scans used manually outline left right hippocampus on multiple coronal slices, add areas adjust slice thickness determine volume. RESULTS Twins combat-related PTSD had mean 11% comparison their twin brothers without combat exposure (p < .05). There no significant interaction by zygosity, suggesting that predisposing risk factor effect. CONCLUSIONS findings are consistent suggest effects primarily due such as combat.