Premorbid brain volume estimates and reduced total brain volume in adults exposed to trauma with or without posttraumatic stress disorder: a meta-analysis.

OBJECTIVE: The primary objective of this study was to meta-analytically investigate whether total brain volume (TBV) and total intracranial volume (TICV) differ between adult participants with posttraumatic stress disorder (PTSD) and controls.
BACKGROUND: TICV reaches maximum growth by early adolescence and provides an estimate of premorbid brain size. Little work has directly examined TBV in PTSD participants, although limited evidence suggests that deficits in brain volume may occur.
METHODS: Using electronic databases, we identified articles containing TBV and TICV data for adult PTSD participants. Data were extracted and effect sizes were calculated.
RESULTS: We identified 8 studies with TBV data (105 PTSD participants and 122 trauma-unexposed controls) and 2 studies with TICV data (18 PTSD participants and 25 trauma-unexposed controls). TBV was significantly smaller in PTSD participants compared with trauma-unexposed controls. In contrast, TICV did not differ between these groups. There were no significant differences in TBV and TICV between PTSD and trauma-exposed controls.
CONCLUSIONS: TBV is significantly smaller in adult PTSD participants compared with trauma-unexposed controls. TICV did not differ significantly between these groups, suggesting that a deficit in TBV occurred at some point after the attainment of maximum brain volume in the PTSD group.