Hippocampal and amygdala volumes in adults with posttraumatic stress disorder secondary to childhood abuse or maltreatment: A systematic review Fatima Ahmed-Leitao a , Georgina Spies a , Leigh van den Heuvel b , Soraya Seedat c,n a South African Research Chairs Initiative (SARChI) in Posttraumatic Stress Disorder, Department of Psychiatry, Stellenbosch University, South Africa b Department of Psychiatry, Stellenbosch University, South Africa c MRC Unit on Anxiety and Stress Disorders, Department of Psychiatry, Stellenbosch University, South Africa article info Article history: Received 15 September 2015 Received in revised form 16 September 2016 Accepted 16 September 2016 Available online 19 September 2016 Keywords: MRI PTSD Early life stress abstract We systematically reviewed differences in hippocampal and amygdala volumes between adults with childhood maltreatment-related posttraumatic stress disorder (PTSD) and healthy controls. Using the terms “adults”, “MRI”, “magnetic resonance imaging”, with “posttraumatic stress disorder”“PTSD”, “child abuse”, and “child maltreatment”, we conducted searches on several electronic databases. We identified 10 studies that met our inclusion criteria; 7 of which were included in a meta-analysis of hippocampal volume and 4 that were included in a meta-analysis of amygdala volume. Mean hippocampal and amygdala volumes were used to determine effect sizes. We found bilateral reduction of both the hip- pocampus and amygdala in the PTSD group compared to healthy controls, with effect sizes of À0.66 and À0.67 for the left and right hippocampus (p o0.00001 and p ¼0.002) and À1.08 and À1.15 for the left and right amygdala, (p ¼0.013 and p ¼0.003), respectively. Confidence intervals were À0.93, À0.39 and À1.26, À0.29 for the left and right hippocampus, respectively. For the amygdala, confidence intervals were À1.92, À0.23 and À1.19, À0.39 for the left and right amygdala. The relatively few studies available for analysis is a limitation. Additionally, sex diverse MRI studies in PTSD are needed to determine whether sex plays a significant role in the hippocampal effects associated with childhood-onset trauma. & 2016 Elsevier Ireland Ltd. All rights reserved. Contents 1. Introduction ......................................................................................................... 34 2. Method............................................................................................................. 35 2.1. Eligibility criteria ............................................................................................... 35 2.2. Search methods ................................................................................................ 35 2.3. Statistical analysis .............................................................................................. 35 2.4. Publication bias ................................................................................................ 35 3. Results ............................................................................................................. 35 3.1. Participants ................................................................................................... 35 3.2. Hippocampal findings ........................................................................................... 37 3.3. Amygdala findings .............................................................................................. 37 3.4. Heterogeneity ................................................................................................. 37 4. Discussion .......................................................................................................... 37 4.1. Hippocampus .................................................................................................. 38 4.2. Amygdala ..................................................................................................... 39 4.3. Sex differences in PTSD .......................................................................................... 39 4.4. Sexual abuse .................................................................................................. 40 4.5. Limitations .................................................................................................... 40 Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/psychresns Psychiatry Research: Neuroimaging http://dx.doi.org/10.1016/j.pscychresns.2016.09.008 0925-4927/& 2016 Elsevier Ireland Ltd. All rights reserved. n Correspondence to: Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, PO Box 241, Tygerberg 8000, South Africa. E-mail addresses: fahmed@sun.ac.za (F. Ahmed-Leitao), ggiocos@sun.ac.za (G. Spies), luellaz@gmail.com, llvdh@sun.ac.za (L. van den Heuvel), sseedat@sun.ac.za (S. Seedat). Psychiatry Research: Neuroimaging 256 (2016) 33–43